Model Engine Maker

Engines => From Plans => Topic started by: arnoldb on January 19, 2013, 09:37:57 PM

Title: Arnold's take on the MEM Corliss
Post by: arnoldb on January 19, 2013, 09:37:57 PM
First off, many thanks to the MEM team for designing up this engine  :praise2: .   It was (and still is!) fun to see the design come together - but my own role is insignificant, and like Jo mentioned in the plans section, just involved some heckling from the side lines.  She's much too modest about her own and Dave's contributions though  :NotWorthy: .

The least I can do is to build the engine.  As those that know my habits by now could guess, this build will be in metric.  I'll leave the imperial one to Tel  ;) .
Bob kindly sent me the CAD files.  My initial thoughts were to keep to the original exact dimensions and just convert things to metric as needed.  However, a lot of the crucial dimensions for the operating geometry and hole sizes are difficult to just convert straight-off, so I scaled the plans to metric using a factor of 24 instead of 25.4.  This will leave the engine a little smaller, but the conversion means that nearly all values scale to easy-to-use metric sizes.

This is by far the biggest engine I've attempted, and there will be some new learning curves involved in terms of work holding, set-ups, and tooling use.    The flywheel is pretty much at the limits of what my lathe can do, and I'm not sure how I'm going to go about making/machining it yet.  I do have some ideas about that though. 

First off, a start on the engine block.  Last weekend, the band saw was put to work to cut a lump off some 60x60mm hot-rolled steel bar I have:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4826.JPG)
After letting the saw go about half-way through, I stopped it, and rotated the stock to let the saw finish on a smaller cross-section.  The blade I have in there is a bit fine for this thickness of cut.

The stock for the cylinder block with a 150mm (6") rule to give an idea of size.
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4828.JPG)
 :lolb: - I just noticed it's sitting on the plan sheet for Elmer's #25.  Massive difference in size!

On to the mill, and a bit of fly-cutting to square up the block of steel and bring it down to size.  None of the edges were square or true - I followed a method Bogs once posted to get things right. (John: if you find some time, could you perhaps re-post your method please ?) :
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4829.JPG)
I use a carbide-tipped left hand turning tool that's been re-ground slightly to give adequate clearances for this in the fly-cutter.  At 1200rpm and a 0.5mm per pass depth of cut, my mill makes short work of things with a good cranking speed.  Just kicks up a heck of a noise, and the surface finish isn't as good as with a nicely honed HSS bit and lower speed.  And those chips come flying of blue-hot, so there's a bit of "dancing" involved to duck them...



Once the block was down to size on the top,bottom, front and back sides (51x51mm), I had to make a choice.  Machine the cylinder faces and cylinder bore on the mill, or use the lathe.  Either method would work, but the largest drill I have is 19mm, and the cylinder needs to be bored out to 27mm.  On the mill, this would mean I'd have to use the boring head to open up the cylinder to size.  I don't mind using the boring head, but it can be a pain and slow to adjust a lot of incremental cuts on it.  I'd have the luxury of using the DRO to drill the cylinder cover mounting holes afterwards though.  On the other hand, it's quicker for me to bore this on the lathe... And face the crankshaft end of the cylinder really true...  And the rotary table is in place on the mill to drill the bolt holes...  So off to the lathe, and clock up the block in the 4-jaw and drill some holes - I started with a center drill, followed by a 7.5mm drill through (It's nice and stiff, and as it's not used a lot, nice and sharp as well), then 13mm, 16mm and finally 19mm:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4835.JPG)

Next to bore out the cylinder to size, and here I hit a snag...  My biggest boring bar for the lathe is actually much too thin for this job  :lolb: .  The machining weather service immediately predicted severe spots of chattering for the rest of the day.  So...  Use the thin boring bar, or make up a new thicker one  :headscratch: ...  My materials stock is a bit low, so I went with the thin carbide-tipped boring bar.  I gave it a good honing on a diamond stone to get a keen edge on the cutting surface, and started boring out the cylinder - with a 0.5mm feed at a time - making the hole bigger by 1 mm on each pass.  It works OK and not much chattering.  My shop session got interrupted before I could finish the bore;  a ring from the cell-phone announced a friend at the front gate, so I snapped a last photo:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4836.JPG)

Hopefully I'll get to finish the bore and drill a lot of holes tomorrow.

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: Jo on January 19, 2013, 09:43:43 PM
 :ThumbsUp: Brilliant Arnold,

My "advanced" version of the engine will be along later ;).   All I will say for now is it has more studs ;D

Jo
Title: Re: Arnold's take on the MEM Corliss
Post by: Stilldrillin on January 19, 2013, 09:55:02 PM
Hi Arnold.
Sitting here, quietly. If that's ok?  ;)

Good luck with the build!  :ThumbsUp:

David D
Title: Re: Arnold's take on the MEM Corliss
Post by: fcheslop on January 19, 2013, 10:03:18 PM
Hi Arnold, watching with great interest
Good luck with the build :ThumbsUp:
best wishes
frazer
Title: Re: Arnold's take on the MEM Corliss
Post by: sbwhart on January 19, 2013, 10:03:47 PM
I've got my eyes ::)  on this one Arnold I'll be quetly following along  :LickLips:

Stew
Title: Re: Arnold's take on the MEM Corliss
Post by: b.lindsey on January 19, 2013, 10:07:13 PM
Arnold, you are off to a nice start and it will be nice to see this one built!!


:ThumbsUp: Brilliant Arnold,

My "advanced" version of the engine will be along later ;).   All I will say for now is it has more studs ;D

Jo

Lest we have any doubts Jo :)

Bill
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on January 19, 2013, 10:18:55 PM
Hi Arnold

This is a build I definetly do not want to miss as I am hoping to do it also as soon as I finish the Kiwi.  Another plus is you are doing it in metric.  Will be attentively following you.

Just one question.  Are you going to use the conversion factor of 24 for all imperial dimensions?

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: Don1966 on January 19, 2013, 10:46:41 PM
Hi Arnold, I am pulling up a chair as well. Interesting built and look forward to see it completed. As always will learn something following you.

Don
Title: Re: Arnold's take on the MEM Corliss
Post by: Maryak on January 19, 2013, 10:57:33 PM
Arnold,

Great start, you'll probably have it finished by the time I drive to Port Adelaide.  :lolb:

Best Regards
Bob
Title: Re: Arnold's take on the MEM Corliss
Post by: sshire on January 19, 2013, 10:58:52 PM
Watching this with great interest as it was a Corliss that ran most of the 1876 Centennial Expostion here in Philadelphia. There was this other thing introduced there; the telephone .
More about the Corliss at the Expisition here

http://www.phillyhistory.org/blog/index.php/2010/05/the-corliss-engine/
Title: Re: Arnold's take on the MEM Corliss
Post by: Bezalel on January 19, 2013, 11:02:10 PM
G'donya Arnald
 
I'll be watching with keen interest.
 
 :cheers:
 
Bez
Title: Arnold's take on the MEM Corliss
Post by: ths on January 19, 2013, 11:21:12 PM
Hi Arnold,

Also watching along with the others.

Cheers, Hugh.
Title: Re: Arnold's take on the MEM Corliss
Post by: Captain Jerry on January 19, 2013, 11:55:17 PM
Arnold,

Good start!  This will be fun to watch.  I have set my display to metric so i can keep up.

Jerry

Title: Re: Arnold's take on the MEM Corliss
Post by: tvoght on January 19, 2013, 11:59:59 PM
I'm delighted to see this! Watching...

--Tim
Title: Re: Arnold's take on the MEM Corliss
Post by: Bearcar1 on January 20, 2013, 12:12:47 AM
   ".............annd, he's off!"  :whoohoo:  I am also one of those that are delighted to see you building up what I think will become a very popular engine among our circles. I must admit that I have been quietly armchair machining this design for the past several days and have been envisioning a split flywheel as was the norm on many of the full scale engines. Still up in the air on that aspect but have some other creative ideas rattling around in the old noggin. You are off to a great start Arnold and I wish you a smooth build.  :ThumbsUp:


BC1
Jim
Title: Re: Arnold's take on the MEM Corliss
Post by: black85vette on January 20, 2013, 12:39:44 AM
Very cool to see you start this.   I like the design but it is much better for us less experienced to see how to go about it and what it is "supposed" to look like.
Title: Re: Arnold's take on the MEM Corliss
Post by: zeeprogrammer on January 20, 2013, 01:12:19 AM
He he. Not that there's any pressure Arnold.  ;D

I can't help but feel you've stepped in it...but unlike some of us...you'll come out clean.

Very much looking forward to your build.
Title: Re: Arnold's take on the MEM Corliss
Post by: propforward on January 20, 2013, 01:30:34 AM
I shall be following your build as well Arnold. You have a great writing style, informative and easy going, and modest as well. You really turn out some great work, and your explanations are exceptionally helpful to the novices among us. Much appreciated.
Title: Re: Arnold's take on the MEM Corliss
Post by: metalmad on January 20, 2013, 01:33:02 AM
Every Arnold Build is Fun to watch
Will be taking along
Where does the Spark plug go??
Pete
Title: Re: Arnold's take on the MEM Corliss
Post by: swilliams on January 20, 2013, 02:29:21 AM
I'm watching Arnold. This will be fun

Steve
Title: Re: Arnold's take on the MEM Corliss
Post by: NickG on January 20, 2013, 09:26:31 AM
Agree with everyone else, this will be great to watch. Well done Arnold  :ThumbsUp:
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on January 20, 2013, 05:31:16 PM
Wow - what an overwhelming response - thank you everyone  :praise2:

Vince, yes, I'll be using the 24 factor for all dimensions.  That brings nearly all measurements to easy-to-use metric sizes for drilling, reaming and fasteners.  1/4" -> 6mm and 1/8" ->3mm etc.

Carl may be very right about me stepping in it...  I'm already wishing my cylinder block was a bit of cast iron rather than this horrible mild steel I have going.  But then, I have been known to do things the hard way sometimes...

I finished boring the cylinder to size, but got a really cruddy finish - the thin boring bar flexed far too much and I just could not get a nice even finish with it - no matter what I tried with cutting fluid and feeds and speed changes:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4837.JPG)

So stuck the Dremel's flex shaft on the toolpost with a grinding stone.  The flex shaft handle is long and thin, and easily provided enough range to grind up the entire length of the cylinder bore to a better finish.  The bore will require some lapping later on though:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4838.JPG)

Off to the mill and rotary table with the chuck.  I used a DTI to locate one side of the workpiece parallel to the X axis and zeroed the RT there:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4839.JPG)

This is an important face on the workpiece - as this face is very square to the cylinder bore, I want to mount the cross-head on it, so the bolt holes must be on the bigger circle as on the  "right view" of the cylinder block on the plans.
I nearly started drilling the holes with just the 19.5mm offset dialed in on the X axis for the bolt circle and cranking the RT 45o for each hole...  Something nagged at the back of my mind though.  I've come to pay attention to these nagging thoughts.  So I checked things, and I would have drilled the holes 22.5o out of position.  It's not a biggie, but the bottom and top hole could possibly go into the area needed for the steam ports if drilled slightly too deep.  So I just made a new list of angles to drill each hole at to get them in their proper locations.  I used a permanent marker to roughly dot where each hole should approximately be to help prevent any brain fart, and then drilled the holes:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4840.JPG)

The workpiece was still a bit long, so I moved things back to the lathe and flipped the workpiece in the chuck and faced it off to length.  I didn't bother to clock it up true in the chuck.  If I wanted to drill the bolt circle for the cylinder head using the RT I should have, but I'll use the DRO's PCD function later to drill these holes:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4842.JPG)

Shop time stopped there for today - it was only a short session:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4843.JPG)

I'll see if I can get anything done during the week, otherwise there won't be any progress till next weekend.

Kind regards, Arnold
Title: Arnold's take on the MEM Corliss
Post by: NickG on January 20, 2013, 05:38:45 PM
Nice work Arnold, I hadn't realised it was quite so big. Cast iron is generally much nicer to work with. I always struggled getting a good surface finish on steels, think the grade of steel plays a large part. Not so bad on the Harrison now but boring is always harder too.
Title: Re: Arnold's take on the MEM Corliss
Post by: tel on January 20, 2013, 07:05:17 PM
Yes, I agree about the cast iron - and went tro great lengths to use it on my version.

Have you considered how the holes for the cover are going to impact on the valve bores laid out that way Arnold? I oriented mine the other way to minimise it. I also used the 'big' bolt pattern on both ends of the cylinder as being more in keeping with 'real' practice.

(http://img.photobucket.com/albums/v332/laneranger/MEM%20Corlis/Topcover.jpg)

(http://img.photobucket.com/albums/v332/laneranger/MEM%20Corlis/covers1.jpg)
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on January 27, 2013, 06:03:50 PM
Thanks Nic.  The type of steel can make a big difference to surface finish.  Unfortunately, I have to make do with what I can find locally, otherwise I have to order in at huge expense...  There's one up side though; trying my best to get good finishes in the mostly poor steel I can get has taught me a lot about  what's involved - I'm pretty happy with the finishes I can get in most non-ferrous metals, 303 stainless and silver steel now  :) .  And yes, it's a big engine - more than double the size of the Popcorn I built.

Tel, thanks mate; yes, I did consider the holes' impact on the valve bore, and drilled them just shy of it.  Looking at your photo, I can now see that I must have had a brain-malfunction when I thought the bolts at the top and bottom holes would interfere with the steam passages, so it might just be better locating the bolt holes like you did  :ThumbsUp: .  I was also considering drilling the bolt patterns both ends with the bigger bolt pattern.  I see you re-arranged the bolt pattern on the steam chest cover as well...

I had a bit of a rough week, and was feeling out of sorts yesterday, so stayed away from the shop and did some menial tasks around the house.  This morning, I decided I'll face the heat and set off to the shop to drill some holes.

After deciding which side of the steel block would become which, I drew some markings on it (to prevent a brain-fart), and set it up in the mill on top of two of my crude home-made parallels to raise it a distance off the vise bed.  This is so that there would be room to pass a reamer through the valve bores.  Then I located it's center on the DRO and also set the vise back-stop up to keep position, as it would be rotated a couple of times.  I started off machining on the "Front" face; this is where the valve gear would be mounted, and I wanted things as accurate as possible here.  My main concern was that the holes for the valve bores might wander slightly as they pass through the block, and I want them accurate at the valve gear side, mostly for the fact that each valve gets a cover with a through-hole on this side, and I want to keep these to a close tolerance.  The valve covers at the "Back" side are just flat plates, and if the hole wandered a bit, it would not matter.
Better stick a photo in, before you get too bored:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4844.JPG)

I've so far enjoyed having the DRO on my mill very much, but today, I really appreciated it.  It's bolt circle function got a good workout; first was the holes for mounting the valve gear - a four hole bolt circle for tapping M3 to mount the valve pivot smack bang in the center of the face.  With the DRO's absolute coordinates set to 0 there, it was easy to move to each of the valve hole centers, set relative coordinates to zero, and drill 5.5mm through, followed by 5.9mm and finally the 6mm reamer.  My reamer is a bit short to completely do each hole though...  At each hole, this was followed by four 1.6mm holes (to tap M2 later) in the valve cover bolt circles.  Everything went well up to the second last 1.6mm hole for the face...  While drilling it, I shifted position slightly, and momentarily applied too much pressure to the feed arm.  SNAP - one broken 6mm drill, with a section stuck in the hole  :facepalm2: :
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4845.JPG)

It's the first drill I've broken in a long time.  It was due to happen at some point, so no use getting upset at it.  Santa arrived very late in my house this year, but brought a nice package full of new milling cutters of all shapes and sizes from Hong Kong about two weeks ago.  Amongst that are ten 1.5mm carbide slot mills that "Peter" popped in free of charge, so that was one option to get rid of the bit of drill left in the hole.  However, that could be messy, and with a tiny bit of the broken bit left sticking out, I decided to gently try and coax it out with a pair of needle-nosed pliers.  After dropping a bit of tapping fluid on it to help lubricate in the hole, I lightly closed the pliers on it while simultaneously twisting the pliers anti-clockwise.  On the second grab, I felt something give, and the bit of drill had twisted out just enough to get a better grab on it to remove it:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4846.JPG)
I was very careful not to drop the bit of drill, as I wanted to see if it was the entire piece.  By carefully checking the end, I could see that it was the entire bit, and thus there were no other significant bits left in the hole.

That was the last of my brand new 1.6mm drill bits, so I grabbed a more-used one, and finished drilling the holes; a lot more carefully!
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4847.JPG)

After flipping the workpiece 180o on it's X axis, I drilled the bolt circles for the Back face around the valve holes:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4848.JPG)

Another 90o flip, and I drilled the bolt pattern for the top steam chest cover:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4849.JPG)

I was about to change the drill chuck for the collet chuck to start milling out the steam chest, when I decided I could just as well finish all the holes on the bottom as well, so I did that:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4850.JPG)

While the workpiece was oriented this way, I started milling out the bottom "exhaust" chest.  Good practice for doing the steam chest on the top, and I got to play around with another new bit from "Peter" - a 10mm carbide slot mill.  I'd decided on getting rid of most of the metal with a 10mm mill leaving lighter machining clearances for a 6mm mill to form the final size of the pocket.  Here I paused to test the depth of the pocket with my once-shiny home-brew depth gauge.  Back when I made it Marv suggested I add a threaded hole to it to screw a bolt through to measure pockets in cases just like this.  Thanks Marv! :
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4851.JPG)
It's important that both the steam and exhaust pockets on this design are done to the correct depth, as it influences the timing of the engine.

You'll see in the photo above the pocket looks too short - and it was.  I deducted the whole cutter diameter from the needed X dimensions, rather than just half the diameter   :-[ .  After milling out that bit more with the 10mm mill, and switching to a 6mm mill, the pocket was machined to size and final depth (45x12x7.5mm):
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4852.JPG)

I felt tempted to mill the top steam chest as well, but it was really hot here and I was getting a bit tired, so I decided not to tempt fate with more machine work.  So I finished hand-reaming the valve bores in the big vise:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4853.JPG)

It's starting to look like a block of Swiss cheese, and there's another bolt circle to drill for the cylinder cover on the left face, as well as the steam ports.  And somehow I feel I should have built a tapping stand first  :facepalm2: :
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4854.JPG)

I'll see what I can get done next weekend; machining during this week will be out, as I'm going on a business trip.

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: Jo on January 27, 2013, 06:19:45 PM
Excellent progress Arnold  8)

And a good save on that drill. You didn;t even have to move the work. :ThumbsUp:

Jo
Title: Re: Arnold's take on the MEM Corliss
Post by: tel on January 27, 2013, 06:56:01 PM
Going along nicely Arnold! Alas, mine is still sitting untouched where it has been for several weeks - I seem (as is usual this time of year) to have grown a tractor on my Gluteus maximus.
Title: Re: Arnold's take on the MEM Corliss
Post by: swilliams on January 28, 2013, 11:02:55 AM
Looking good Arnold. Yours too Tel, hopefully you get that bucolic boil off your bum soon and get back in the shop  :Jester:

Steve
Title: Re: Arnold's take on the MEM Corliss
Post by: black85vette on January 28, 2013, 02:30:24 PM
Wow.   That is an extreme amount of drilling.   Glad you recovered the broken bit!  :cheers:

I see that you drill first and then tap later.   I have broken enough taps (poor technique no doubt) that I drill and then tap each hole one at a time so I am sure that my tap is lined up and vertical.

Looking good.
Title: Re: Arnold's take on the MEM Corliss
Post by: b.lindsey on January 28, 2013, 02:50:30 PM
Both of these are coming along well!!  Seeing that crosshead attached to the cylinder really makes it start looking like an engine too!!  Heres to getting more shop time and or extricating tractors from posterior areas for both of you :)

Bill
Title: Re: Arnold's take on the MEM Corliss
Post by: Don1966 on January 28, 2013, 06:44:36 PM
Looking good Arnold, and that is a bummer to break a tap with all those holes to drill and tap. I think I would of loss my cool on that one. Good save though. I will be following you closely and enjoying your work as always.

Don
Title: Re: Arnold's take on the MEM Corliss
Post by: Alan Haisley on January 28, 2013, 08:53:50 PM
Arnold, all of your pictures zapped out. They were there yesterday when I looked at this thread.
Alan
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on January 29, 2013, 03:48:31 PM
Thanks All  :)

Tel, you should know by now that farm implements affects shop time...  Are you over that heat wave ? - it's reached right up here...

Rick, this was a small amount of drilling... Wait till you see what Jo have in mind  >:D .  I'm quite fortunate with taps; only ever broken one.  But I follow a rigorous tapping regime.  The metric taps I use have 3 taps per set - and they don't quite follow the US / UK tapping practice.  The first tap is a starter tap, and by itself pulls and starts a shallow thread nice and square in the hole.  The second tap is not to full thread size, but follows the starter tap's thread easily and taps easily.  The third tap takes the thread to full size.  I use these taps each in turn, without skipping any one of them on a hole, and as a result I get good results tapping holes.  As they don't do full thread diameters, I don't need to follow the practice of tap a bit, twist back, tap a bit.  They just screw right in without any stopping, and right out again.  So even using all three taps, things are relatively quick.

Alan, the pictures should be back now.  My hosting site applied my annual domain registration fee to the wrong account, and as a result my domain expired - when that happens they take the domain off-line :facepalm2: - fortunately they now found the accounting error and reinstated my domain.  So the piccies are back, and should be safe for another year.  They'd better not stuff up next year; I'll check up on them better anyway  :slap:


Bob (Maryak) made up a slightly revised drawing of the cylinder showing measurements to drill the port holes before machining out the steam & exhaust chest pockets.  Unfortunately that email is sitting on my home PC now, and I'll only be able to access it again at the end of the week. Basically I'm going about getting the steam passages drilled the hard way, but I have a couple of ideas.  All that have to wait till the weekend though.  I considered bringing the cylinder block and taps along on my business trip, but somehow I don't think the hotel would be happy with the smell of tapping fluid pervading the room  >:D

Kind regards, Arnold.
Title: Re: Arnold's take on the MEM Corliss
Post by: Maryak on January 29, 2013, 10:24:36 PM
Arnold and All

To save you the trouble, I have attached the revised page here.

Best Regards
Bob
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on February 03, 2013, 04:42:21 PM
Thanks Bob  :NotWorthy:

Saturday was a lost cause on machining... It reached all the way to 39C here, and I just don't go to the shop when it's that hot.
Today was a bit cooler, so I got in a bit.  Not much to show for it though...

The cylinder block still needed the port holes, and silly me had to go about it the hard way, as I didn't think things through carefully enough right from the start.

First of all, I needed a way to set the cylinder block at the correct angle to drill the port holes - that's 15o .  One of the items lacking in my tooling area is an angle vise - so I had to improvise a bit.  I grabbed a block of 10mm flat bar, and milled one end and one side nice and square.  Then I roughly sawed off a tangent section at about 15o.  I used my precision protractor to set that up in the mill to mill the block to a fairly accurate 15o angle:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4855.JPG)
That protractor is a prized bit of tooling in my shop.  The set-up trapped it there, but it was easy to take out by just loosening the adjustable arm and pulling it out.  There's no way I'd leave it in place while milling the workpiece.

After milling the block of steel to size, I tested it against the protractor again after I removed it from the vise - just to make sure it didn't move while milling the tangent:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4856.JPG)
 ;D I now have a half-accurate 15-90-75 degree triangle added to the shop tooling.  Not high precision, but it'll do for most jobs that come along.

While on my business trip this week, I had lots of time to think while driving.  The simplest solution I could come up with for drilling those port holes without the drill wandering at the start was to make a drilling guide from some 6mm silver steel - that's a close fit in the valve bores.  I grabbed a bit of silver steel, and accurately cross-drilled the 1.6mm hole through it after skimming a flat on it with an end mill:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4857.JPG)

Setting up for drilling the port holes was not too difficult.  I set the workpiece op on the newly made triangle, and also set the vise stop to block both the triangle and the workpiece:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4859.JPG)

Then I fiddled with the x axis until a 1.6mm drill easily passed through the drill guide - I did this with the drill guide inserted into the valve bore, but with the drill and hole outside of the block so I could check for alignment and deflection:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4858.JPG)

Then I proceeded to drill the holes - by moving the y axis as needed and then manually twisting the drill chuck while twiddling the guide into position, and then starting the mill:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4860.JPG)

Things didn't turn out quite as well as I'd hoped, but it should work.  It would have been better to pre-drill all the holes in the drilling guide rather than fiddle with it for each hole in the block:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4861.JPG)

(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4862.JPG)

Only once I was done with the holes, I realized I should have drilled them 1.5mm rather than 1.6mm...  Oh well, the engine should breathe easier.

As a last drilling operation on the block, I drilled the left hand side for the cylinder cover.  Easy-peasy; center on the hole, and let the DRO calculate the bolt circle.  I went for the smaller PCD as per the plans on this one:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4863.JPG)

Now all that remains on the block is tapping, honing the bore, and a lick of paint.
"All"...  Just 52 x M3 holes and 32 x M2 holes to tap...  Each hole three times with a starter, middle and bottom tap...  I feel an interruption coming on for a quick tooling project  :naughty:

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: mklotz on February 03, 2013, 04:50:19 PM
Very clever setup, Arnold.  Obviously you thought that one through thoroughly before starting.

Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on February 03, 2013, 04:57:45 PM
Arnold

Following you like a shadow and realising that steam engines are a different kettle of fish from i.c. engines.  New terminology to learn.

I also use 3 set metric taps and never realised that they are self-centering.  Good to know.

Yesterday I went to my favourite metal supplier to see if I can get the required material for the flywheel and found out that the largest diameter he stocks is 120mm.  That put a damper to my plans.

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: propforward on February 03, 2013, 05:00:43 PM
That is a very well thought out approach - very impressive.
Title: Re: Arnold's take on the MEM Corliss
Post by: Jo on February 03, 2013, 05:06:58 PM
Now all that remains on the block is tapping, honing the bore, and a lick of paint.
"All"...  Just 52 x M3 holes and 32 x M2 holes to tap...  Each hole three times with a starter, middle and bottom tap...  I feel an interruption coming on for a quick tooling project  :naughty:


So have you already done the studs  for it :naughty:
----
Nice progress, those ports are likley to be the thing that puts most people off with a corliss :ThumbsUp:.

Jo
Title: Re: Arnold's take on the MEM Corliss
Post by: NickG on February 05, 2013, 09:29:16 AM
looking good Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on February 06, 2013, 04:57:54 PM
Thanks All  :praise2:

Vince, the taps do tend to pull themselves straight if you start with the first one.  Just use a light touch in sort-of keeping it aligned at the start.  Not much use for shallow holes though; sometimes the starter tap's point will bottom out before it's even started to cut the thread.  That's when I resort to a tapping block to keep the tap straight.  The terminology is slightly different, but not really that much - most of it is based on the differences in design between IC and steam engines.

Quote
So have you already done the studs  for it (http://www.modelenginemaker.com/Smileys/default/naughty.gif)
Sadist  :ROFL: How did you know I've got 2.5m of 3mm 303 rod? The 2mm studs I'll make from full threaded sections though.  Can't ruin my reputation for being a lazy rotter  ;)
If it weren't for the fact that the tapping fluid vapors could be very harmful to Shrek the parrot, I'd have brought the small lathe into the house for that already... There's LOTS of space on the dining room table.

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on February 09, 2013, 07:08:02 PM
On to today's bit - there's not much to show for half a day's shop time though...

I started on the crosshead guide.  With the going-rate of steel here I tend to be frugal, and unless it's absolutely necessary that a workpiece be made from one solid piece and mostly turned to chips, I rather make things from bits and stick them together if possible.  The crosshead guide is a candidate for this.  At  81mm long, with a 3mm thick 48mm diameter flange on one end and the rest of the length turned down to 27mm; rather than taking a bit of 50mm diameter x 100mm long round bar (the extra length is for chucking allowance) and turning it down to the sizes needed, I'll just make the crosshead from two assemblies - a bit of "pipe" from some 32mm hot-rolled steel I have, and the flange from some plate stock silver-soldered to it.
With a lump of the 32mm bar chucked up, I gave it a single pass to under-cut the mill scale - that stuff toasts a HSS toolbit very quickly if you let it "rub" against it:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4864.JPG)
After a quick re-sharpen of the toolbit on the oil stone, I turned it down to 27mm.

Then the parade of drills started.  A 4.5mm pilot hole as deep as I could get it.  The 4.5mm drill bit is much too short for the entire job, but a good start.  Why 4.5mm? - well, it's one of the lesser-used drills in my drill index, so nice and sharp, and being one of the more "standard" sizes, cheap to replace when it dulls.  It's also fairly stiff and not inclined to wander too much in the lathe.  I followed that by a bit of a hog - a 13mm drill till it bottomed out on the pilot hole.  My old Myford happily breezes through this type of operation, but once the big drill hits the bottom of the pilot hole, one really needs to force the tailstock handwheel to carry on.  The lathe will do it, but I can't help but feel the wear on the tailstock feedscrew and nut gets excessive, so at this point I ruffled through the drill index to find a smaller drill that would go all the way through the workpiece.  The 8.5mm drill did that.  What's nice about having the bigger hole for most of the way already, is that the swarf from the 8.5mm drill had lots of room in the 13mm section, so less "pecking" needed to go all the way.  Once the 8.5mm drill was all the way through, I followed it with the 13mm drill again all the way through. I only have two drill bits above 13mm - a 16mm and a 19mm - so these followed.  Here I'm getting ready to poke the 19mm drill through:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4865.JPG)
While it was not strictly necessary to drill the hole all the way through the workpiece, there was some boring to follow to get to the required 21mm diameter.  The through-hole meant that swarf from the boring operation could also go through the hole and into the lathe spindle - making things just a bit easier than on a blind hole.

After all that drilling, the lathe's motor was running a bit warm, so I gave it a break and started tapping some holes in the cylinder block.  I was considering making up a tapping stand first, but I'd rather like to carry on with this project and do the tapping stand as a separate project:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4866.JPG)
 ::) The M2 tapping session came to an abrupt end - broke the number 2 tap in the third hole I was tapping.  Fortunately it snapped where the threaded section on the tap becomes plain, so there was enough left sticking out the hole to just turn the left-over bit out with pliers.  The other M2 tap I broke a couple of years ago was unfortunately also the number 2 - so I couldn't even fall back on the old set to continue...  I just hope the local supplier have stock.

Back to the crosshead for boring.  I tried with one of my existing 6mm boring bars, but right at the start of the start of the cut it chattered more than the Mad Hatter.  This would never survive the looking glass, so I spent a couple of minutes in Wonderland to try and figure things out.  Right.  A looong bore. (Well, in my experience of machining anyway).  There's a lot of workpiece hanging out from the chuck - so some support needed as well.  And a rigid tool good for four inches of work. 
A quick job on the band saw and milling  machine left me with a bit of 16mm silver steel rod cross-drilled for 4mm HSS stock and a 3mm grub screw to keep it in place.  A couple of flats milled on the  other end encouraged it to fit in QCTP holder.  To add a bit of rigidity to the workpiece, I broke out the lathe's fixed steady, set it's fingers up close to the chuck, and then clamped it down close to the end of the workpiece on the lathe bed and added some thick oil to lubricate it:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4867.JPG)

After boring out the workpiece to 21mm from the 19mm drilled hole, I ended up with a bore finish that's sort of "OK":
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4868.JPG)
Not quite up to the standard I expect from myself, but this is a new learning curve for me, so I'll settle for it.  The bore looks a bit rough in the photo, but feels smooth, and should work.

Like I said, not much to show for a bunch of hours in the shop, but some progress.

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: zeeprogrammer on February 09, 2013, 07:57:39 PM
Nice post Arnold. I liked the explanations.
Sorry about the tap.
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on February 09, 2013, 09:49:11 PM
Thanks for the update Arnold.

Always look forward for the weekend to arrive to see your progress.

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: Maryak on February 09, 2013, 11:58:19 PM
Good Job Arnold  :NotWorthy:

It's nice to see the fruits of our labours in action and it gives us an idea of what's required tooling wise to build the engine.

Best Regards
Bob
Title: Re: Arnold's take on the MEM Corliss
Post by: tel on February 10, 2013, 12:11:18 AM
Quote
I rather make things from bits and stick them together if possible.  The crosshead guide is a candidate for this.  At  81mm long, with a 3mm thick 48mm diameter flange on one end and the rest of the length turned down to 27mm; rather than taking a bit of 50mm diameter x 100mm long round bar (the extra length is for chucking allowance) and turning it down to the sizes needed, I'll just make the crosshead from two assemblies - a bit of "pipe" from some 32mm hot-rolled steel I have, and the flange from some plate stock silver-soldered to it.

I did mine exactly the same way. only with cast iron and Loctite. Glued the oversized flange on and finish turned it after the Loctite had cured.

(http://img.photobucket.com/albums/v332/laneranger/MEM%20Corlis/Topcover.jpg)
Title: Re: Arnold's take on the MEM Corliss
Post by: Don1966 on February 10, 2013, 01:51:12 AM
Glad to see more updates Arnold, she sure is shaping up. Waiting for you next update.

Don
Title: Arnold's take on the MEM Corliss
Post by: NickG on February 10, 2013, 10:19:51 AM
Looking pretty but purposeful! Nice work.
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on February 16, 2013, 07:55:29 PM
Thanks All  :praise2:

Carl, the tap was bound to break at some point - it's gone through at least a hundred holes, so I won't complain, especially since it was easy to get out of the hole  ;)

Like Bob mentioned, it's giving an idea what's needed for tooling...  I wish I'd made that boring bar earlier; it would have been much easier to do the cylinder with it as well...

I had a bit of a hectic week; I've been assigned to a large project that requires a lot of investigation and report writing at work.  I'm enjoying the project, but had to put in some extra hours in the evenings to make some deadlines.  On Monday evening my report-writing got interrupted pleasantly by my neighbour calling me over the wall.  He promptly handed me these:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4869.JPG)
Two of the smallest sized 400kPa (58psi) pressure gauges they sell.  Just about perfect for adding to small 40psi boilers  :whoohoo:

On to the project at hand.
I parted off the "tube" for the cross-head, on purpose making it 1mm shorter.  Then it was clamped up in the mill - I clamped it length-wise in the vise, as I didn't want to distort the bore - there was some fairly heavy-handed machining coming up, and I wanted it secure.  If it was clamped across in the vise, milling out the pockets would weaken it quite rapidly and it would easily distort or come out of the vise.  Just my thoughts - not necessarily correct though.  Then I located it's center, and drilled two 6mm holes through it:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4870.JPG)
The holes were then enlarged to 13mm.

A 14mm mill worked well to mill out the slots - I just poked it through one of the 13mm pre-drilled holes in the top, milled along to the next hole, and then finished with 0.5mm side-cuts along the length to get the slot to 15mm width.  The slot width isn't too critical; I could have left it at 14mm, or even taken it up to 16mm (I don't have a 15mm mill, but I do have a couple of 16mm ones).  Once the top slot was done, I repeated the process for the bottom one.  I nearly trashed the end mill though... while cranking it down to start in the hole, I forgot that the inside curve in the "pipe" would mean that the cutting flutes would contact the workpiece before it was close to the hole.  Fortunatley the cutter handled it well, and just took some big chips out very quickly without breaking.
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4871.JPG)

After a bit of de-burring with a small half-round file, the bit was done:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4872.JPG)

I thought I had a bit of 50mm steel rod in stock to make the "flange" for the cross-head guide from   :noidea: .  Nope; it's only 40mm and way too small. It needs to be 3mm thick - so I had a look around for plate -  :ShakeHead: .  I have lots of 10x60mm steel flat bar.  Cruddy stuff to machine, but it will have to do - so I hatched a machining plan and cut a block of it.  As so often happens (for me at least), the choice was machine it on the mill or on the lathe. 
Well, I'd already had a mill session, so on to the lathe.  I used an old bearing outer shell as a parallel, and after crudely centering the workpiece in the 4-jaw chuck with eyeball MK1, tied the bearing shell down to two adjoining chuck jaws with a piece of binding wire:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4873.JPG)
Carl - and maybe others - like a bit of explanation...  The bearing shell would remain in the chuck while machining.  By tapping on the workpiece while chucking it up, the shell can be made to sit tight between the workpiece and chuck body, but I don't fully trust this.  My lathe's 4-jaw chuck is at least a year older than I am and still in pretty good nick, so I don't want that shell coming loose while turning and rattling around in there and possibly marring the chuck.  By tying it down to just two adjacent chuck jaws, its possible to loosen the other two chuck jaws to flip the workpiece around without having to redo the binding.  Cable ties works just as well for this, but I'm out of stock...
Note that there was no possibility for the "parallel" to escape between the chuck jaws.  NEVER EVER leave parallels in a chuck if there's any possibility that they can escape while working.

After facing the mill scale off one side of the workpiece, it was flipped around in the chuck, and then faced down to 3mm thick:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4874.JPG)

Some drilling and boring later, there was a hole in the middle to match up with the "pipe" section done earlier.  There's an "inside" flange left at the back that is 1mm thick.  This is also the reason why I made the pipe section 1mm shorter.  The pipe section must fit very square to this bit, and the inside flange will help with that.  The pipe bit is a light push fit into the hole, and I also added a bit of chamfer to the hole.  This is for space for solder to wick into to make the final joint a bit stronger
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4876.JPG)

Here's how things fit together at the end of my shop session:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4878.JPG)
The pipe bit fits snugly in place, and the chamfer ring is clearly visible.  Earlier I mentioned that I'll silver solder these together, but I'm going to go with electronics solder.  It should be more than strong enough in this application, and there will be less cleanup involved.

Horror of horrors...  I've got measles:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4879.JPG)
NOT.  A stream of blue-hot chips splashed over me when I started - slightly over-vigorously - on facing off that square block on the lathe.  I guess it's the hobby-engineer's equivalent of lactic acid  :LittleDevil:

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: Jo on February 16, 2013, 08:04:28 PM
Thanks All  :praise2:

Carl, the tap was bound to break at some point - it's gone through at least a hundred holes, so I won't complain, especially since it was easy to get out of the hole  ;)

 :o I have a 12BA tap that I cut many more thread with, in steel. ;)

 :headscratch: I still don't understand what the binding wire was for :shrug:

Jo
Title: Re: Arnold's take on the MEM Corliss
Post by: tel on February 16, 2013, 08:08:25 PM
Quote
I still don't understand what the binding wire was for

To stop the packing piece slapping around.
Title: Re: Arnold's take on the MEM Corliss
Post by: zeeprogrammer on February 16, 2013, 08:36:50 PM
Glad you got some time in the shop Arnold.
Nice explanation too. Thanks.
Title: Re: Arnold's take on the MEM Corliss
Post by: b.lindsey on February 16, 2013, 09:40:48 PM
Nicely done Arnold, and as usual, very well documented also.

Bill
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on February 16, 2013, 09:54:52 PM
Always great to see your progress on this build Arnold.

I finally managed to find a slice of mild steel for the flywheel and most probably next week I will start a thread on another MEM Corliss and then we can compare notes as I will be starting from the flywheel end of the engine.  Wish me luck.

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: b.lindsey on February 17, 2013, 12:57:05 AM
I have acquired the materials for the cylinder, crosshead and flywheel, but will be watching you guys for a while yet.

Bill
Title: Re: Arnold's take on the MEM Corliss
Post by: Don1966 on February 17, 2013, 01:08:41 AM
Nice progress Arnold, and you must of gotten a new camera. Those photos are superb and well documented too.
Title: Re: Arnold's take on the MEM Corliss
Post by: steamer on February 17, 2013, 08:21:12 AM
Great write up Arnold!   Norm used to give me the "measels" on a regular basis...I got one of these...and it works great!  especially with brass!

http://www1.mscdirect.com/cgi/NNSRIT2?PMAKA=02599041&PMPXNO=4761429&cm_re=ItemDetail-_-ResultListing-_-SearchResults


Poke around...I'm sure someone has one in your neck of the woods.....

Dave
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on February 24, 2013, 12:15:30 AM
Thanks All  :praise2:

Jo, like Tel said, I didn't want that ring slapping around.  You shouldn't have mentioned that good tap of yours - it jinxes it  :LittleDevil: .  The #2 2mm tap I broke has a whole story behind it...  The only tap I ever broke before this one was also a #2 2mm - in some work-hardened stainless.  The first cut this one made was right trough that same stuff to finish that hole, so it may have been slightly doomed right from the offset  :) .

Good luck Vince  :ThumbsUp: - or rather, Happy Machining!  Yes, I'm following along, and all of us that's busy building it can compare notes  :) .  Once I get around to the flywheel, things may just involve a lot of heat and a big hammer to start off with...  I'm struggling to find material for it locally, and my budget's a bit tight at the moment, so I'll have to improvise a bit...

Bill, you're doing a great job on the Wright Brothers 1903 - finish that one off first  :ThumbsUp: .  The Corliss is still untested, so it might be good to check things out before you start on it.

Don, not a new camera - the same one, still with the broken corner  ;) The only difference is I have to take the photos from a bit further away compared to my previous builds, as the parts are so much bigger.  The cylinder block on its own is bigger than a couple of engines I've built  :facepalm2:

Dave, thanks bud, but nothing like that here on the savannah.  I have a sheet of perspex that I got especially for making up a chip-screen - but that's just another round tuit...  The only times I remember I need to make it is when a job like this comes along on the lathe, or when I forget to check which way the chips will go when fly-cutting with a carbide tool on the mill  :Lol:

Progress is a bit slow on the build, but I've had a couple of challenging "work" work assignments thrown my way.  Last Sunday, I took the day off engine building for some good old-fashioned book studying.  I planned a full day in the shop today, but while running some errands this morning, I got a call from a friend who needed some help.  Family and friends take precedence, so I only ended up with half the shop session I had planned.

I started off with centering the rotary table on the mill, moved the 4-jaw chuck to the rotary table on the mill, and drilled the mounting holes in the flange:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4880.JPG)
You might notice the piece of wire holding the "parallel" (packing as Tel called it) is gone here.  I needed to tap the packing around a bit to prevent the drill catching on it when breaking through the holes.  HSS drills don't like drilling into hardened bearing shells.

Back to the lathe, and I used a grooving tool to trepan a ring into the workpiece at about 1mm larger in diameter than needed.  I wasn't feeling in the mood to grind up a new toolbit for this job, and this grooving tool had just enough clearance on the "outside" side at this diameter, though it wouldn't do the job completely.  It also does not have a very deep sharpened reach, so when I saw it starting to raise a burr on the inside ring, I stopped:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4881.JPG)

With the bandsaw in vertical mode, I cut away most of the outside.  The groove made things easier to follow and get fairly close.  While the bandsaw blade can follow a slight curve, this ring is much too small for it to follow, so I cut away things in sections; corners first at about 45o to just intersect with the groove, then the smaller left-over bits either side and so on:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4882.JPG)
I didn't want to leave too much "meat" on the ring, as the next step was soft-soldering it to the "pipe" section.  The tin/lead solder I used is not very strong, and while more than adequate for this specific application in it's final use, it would likely not stand up to machining too much of an interrupted cut to get things to size.

Next up, the soldering.  After cleaning oil residues of the two pieces with some methylated spirits, I just coated the inside of the ring with some plumbers' flux, stuck the bits together, checked alignment of the slots in the pipe section to the holes, and added a ring of solder:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4883.JPG)
Can anybody spot the boo-boo about to happen here ?  :-[

A bit of heat from the plumber's torch from below had the solder flowing and the joint made - definitely not as pretty as I'd hoped, but it would do:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4884.JPG)

Spotted the boo-boo yet?  No?  The "pipe" section was upside-down.  The grooves in the "pipe" section is offset closer to one end, and I'd gone and soldered it in the wrong-way around  :???: .  So I re-heated everything took it apart, wiped away as much of the solder as possible with a bit of kitchen paper, and re-soldered it the correct way around.  Yippee... Job done!  Uhrm... Oops... No...     Rats  :facepalm: I didn't check the alignment of the grooves in the pipe section relative to the mounting holes in the flange  :lolb: Stupid bugger :insane: .  So once again a bit more heat till the solder flowed, and I rotated the pipe section with a leather glove to match up correctly with the mounting holes ,purely by eyeball MK1.  This is not overly critical - the cross-head has a lot of contact area in the pipe section of the cross-head guide, so if it looks OK it should be OK.  The critical bit here is that the pipe section be very square to the flange, and the inside lip I machined on the flange earlier helped with this.

So, after all the soldering boo-hah, I finally got the workpiece back on the lathe to turn the flange to the correct diameter.  I clocked it up in the 4-jaw chuck again:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4885.JPG)
There was no real need for this; I could just have used the self-centering 3-jaw, but I like a bit of a personal challenge.  And anyway, my 3-jaw chuck is out by miles and a bit bell-mouthed, and I'd rather take a bit of accuracy here.  With the cut-outs on the pipe section, the 3-jaw would also be more inclined to distort the workpiece.

One bit of kit I got with my lathe is very nice indeed - though I haven't mentioned it very much.  The revolving tailstock center has interchangeable bits, and besides the normal sharp 60o center, it has a larger cone center and so on.  I fit the cone center for the next step; it's larger than the bore in the pipe and added some rigidity:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4886.JPG)

And turned the flange down to size.  Light cuts, so as not to break the soft soldered joint:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4887.JPG)

Finally, I had the cross-head guide done:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4888.JPG)

This engine is taxing my available material, so I settled on some 25x5mm flat bar to start the steam and exhaust cover plates from:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4889.JPG)

Those bits were machined down to length and width (60x23mm), and then I spotted the hole positions for drilling, leaving a lightly spotted hole in the center for more machining later on:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4890.JPG)
 :wallbang: I really need to get myself a set of parallels; that lot was just mounted by fingertip-feeling across the top of the vise's fixed jaw.  It's not good practice and a nonchalant personal vice I need to address...

After a bit of drilling, it looked like this:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4891.JPG)

The second one followed, and I two covers-in-making.   A bit thick, but in progress.  The result of today's work:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4893.JPG)

Not a true assembly shot, but this is what things looks together like right about now:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4894.JPG)

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: zeeprogrammer on February 24, 2013, 12:47:39 AM
Progress is a bit slow on the build, but I've had a couple of challenging "work" work assignments thrown my way.

Oh whine whine whine. A bit of 'work' getting in the way? You've been throwing that up a bit too often lately.  ;D Actually, I'm rather envious. I'm suffering the same issues but you still seem to manage some shop time.  :cussing:

Can anybody spot the boo-boo about to happen here ?  :-[

Not me. Never seen a boo-boo about to happen from you.  ;D

Spotted the boo-boo yet?  No?  The "pipe" section was upside-down.  The grooves in the "pipe" section is offset closer to one end, and I'd gone and soldered it in the wrong-way around  :???: .

You apparently have 'zeepitis'. I didn't think it was catching...much less transferable via forum. Sorry about that.

I sure enjoy reading your posts Arnold. I enjoy learning your machining techniques as well as your reaction/response to 'challenges'.
Title: Re: Arnold's take on the MEM Corliss
Post by: Don1966 on February 24, 2013, 12:52:58 AM
Arnold , another great post and well documented photos. Bummer about the flange it happens to all of us.  I usual find myself doing stupid things when I have to many other things on the brain. Or I just get in too much of a hurry. As always love to follow your progress.

Don
Title: Re: Arnold's take on the MEM Corliss
Post by: Pete49 on February 24, 2013, 01:56:14 AM
Arnold a tip I picked up somewhere for soldering is to lay some talc (engineers?) chalk at the limit of where you want the solder to run and presto the solder stays in that area nice and neat. My gunsmithing mate got his from Brownells a few years ago when owning guns (hunting ) wasn't the bad thing it is now due to ........no don't wan't to be told off  :Lol: but the trick is good
Pete
Title: Re: Arnold's take on the MEM Corliss
Post by: Bearcar1 on February 24, 2013, 03:10:07 AM
Think of the bright side Arnold, you could have done that joint with true silver solder,......now THAT would have been a real pig to have to straighten out. I'm liking your progress so far.I don't know how many times I've stared at these drawings and machines the pieces in my head. Perhaps one day I will get off my bum and do something about it. Always a pleasure to watch you work as usual.  :ThumbsUp:


BC1
Jim
Title: Re: Arnold's take on the MEM Corliss
Post by: Maryak on February 24, 2013, 03:51:02 AM
Great stuff Arnold,  :praise2:

As Jim said, Glad it wasn't hard solder or braze or TIG etc. That may give rise to a bit of drill the bolt holes after joining.

Best Regards
Bob


Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on February 24, 2013, 07:21:09 AM
Good save Arnold from that boo-boo.

Correct me if I am wrong.  So that cylinder with the two slots is called the crosshead?  What is it's purpose?

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: tel on February 24, 2013, 07:25:41 AM
Good save Arnold from that boo-boo.

Correct me if I am wrong.  So that cylinder with the two slots is called the crosshead?  What is it's purpose?

Vince

Actually, it is the crosshead guide, it's purpose is to guide the end of the piston rod in a straight line. The crosshead proper is the bit that couples the piston rod and connecting rod together and works inside the guide
Title: Re: Arnold's take on the MEM Corliss
Post by: sbwhart on February 24, 2013, 07:53:13 AM
Going well Arnold  :ThumbsUp: :ThumbsUp: :ThumbsUp:

Nice use of solft solder, I forget  :facepalm: just how good a soft soldered joint can be.

Stew
Title: Re: Arnold's take on the MEM Corliss
Post by: Jo on February 24, 2013, 07:59:44 AM
Is the soft solder going to be strong enough?  :noidea: It is easy to clean off, a rotary wire brush will make short work of cleaning it up. :ThumbsUp:

Jo
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on February 25, 2013, 09:24:22 PM
Thanks All  :praise2:

Don, yes, I'll blame it on a bit of a hurry - seeing as I'm one of the younger members I can't claim a "senior moment" - yet...

"Zeepitis" - Carl, perish the thought.  It's intrinsic to model engineering, so most of us have it anyway.  I could just have kept quiet and most likely nobody would have noticed, but maybe someone learns a lesson from the booboo  ;)  I know how you're feeling about not getting to the shop...  But a little life-lesson I've learned is that I make a little "my" time once a week.  That may sound selfish, but it's not intended to be.  It's just that it gives me a chance to maintain another perspective on things, and I've found that this helps me cope better with all kinds of other happenings life throws at me.  I'm most definitely not whining - in fact, right now I have the best job I've had in all of my career.  It takes a lot of work to meet and try and exceed the standards expected.  Not necessarily those of my bosses and clients, but to my own personal standards.  And I'm my own worst critic  ;)

Great tip on the chalk line Pete  :ThumbsUp: - I just got a bit carried away with the flux brush on this one  :Lol: ; fortunately its easy to clean up.

Jim & Bob, yes, I'm really glad that wasn't silver solder  :-X .  Jim, if you get started now, you might just beat the cross-continental postal service  ;)

Vince, what Tel said.  It's one of the engineering terms that's rather unique to steam engines; I don't know of any IC engines that use crossheads and crosshead guides, but there just may be some out there.

Cheers, Stew - I like to use soft solder where it would work.  Less heat involved, so less chance of parts warping, and actually pretty cheap as well.  A roll of solder goes a long way; the two rolls I have I've had since my student days 18+ years ago, and they're still more than half full.  Or as an engineer might put it, the spools were too big  :LittleDevil:

Jo, in this application the soft solder is more than strong enough.  The crosshead guide should never see any significant forces applied to it.  That's why Tel's solution with Loctite is just as good.  In fact, the crosshead guide will be supported in a hole in the frame on the outer end.  If one was to use a grub screw to secure it there, a permanent joint would not even be necessary (much like the way Stew's Potty Popcorn engine's crosshead guide is mounted). 
The only reason I wanted the stronger joint was so I could mount up the crosshead guide to machine the last bit off the flange.
 ;D Yes, a wire-brush takes away excess soft solder quickly - so does a bit of green Scotch-Brite  :ThumbsUp: .  Tends to clog up files really quickly, but if started with a well-oiled file pulled back through a well oiled (close to soaking) rag after each stroke, that works well too to clean out the cuttings.

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: fcheslop on February 25, 2013, 10:16:54 PM
Hi Arnold,Tipex correcting fluid also works as a resist when soldering even for hard soldering
She is looking nice
best wishes
frazer
Title: Re: Arnold's take on the MEM Corliss
Post by: zeeprogrammer on February 26, 2013, 12:16:49 AM
"Zeepitis" - Carl, perish the thought.  It's intrinsic to model engineering, so most of us have it anyway.

Hear that everyone? Most of you have 'zeepitis'.  :facepalm2: Sorry about that.
I suspect it's just another name for that which ails us sometimes.
Arnold-itis
Dave-itis
Eric-itis
Jo-itis
Bill-itis
Don't mean to leave anyone out. You all get it from time to time.
Except for Marv-itis.

Arnold...I know you know I'm just having a poke at you.

Your threads are educational, inspiring, and entertaining. So try and increase that bit of 'my' time you have.
Title: Re: Arnold's take on the MEM Corliss
Post by: mklotz on February 26, 2013, 12:35:43 AM
Quote
Don't mean to leave anyone out. You all get it from time to time.
Except for Marv-itis.

I'm curious.  Just what symptoms would characterize the dreaded Marv-itis.  Perhaps a sudden outburst of optimism* or good will?  (Believe me, if you think I'm bad now, wait until you see me cheery.)

SJUhlRoBL8M
Title: Re: Arnold's take on the MEM Corliss
Post by: Maryak on February 26, 2013, 12:54:53 AM
I don't know of any IC engines that use crossheads and crosshead guides, but there just may be some out there.



Large Direct Drive Marine Diesels use a Xhead and Guide, they also fire on both strokes (up as well as down). Max rpm 140, min rpm 25. The worlds largest is 14 cyl 90,000 hp and the crankshaft weighs 300 tons!!!

Best Regards
Bob


(http://i389.photobucket.com/albums/oo340/Maryak/MANBWK108ME-C_zpse103dac6.jpg)
Title: Re: Arnold's take on the MEM Corliss
Post by: Captain Jerry on February 26, 2013, 01:27:03 AM
And don't forget the marvelous Mery 6 stroke cycle engine shown here

http://www.martinmodel.com/MMPengines-subfiles/engines-mery.html

And here is a picture guy scraping the cross head guide and one of a couple of guys checking the fit of the cross head shoe at Doxford (opposed piston 2 stroke diesel)

http://www.shipsnostalgia.com/guides/images/a/a4/Handscrapingcrosshead.jpg
http://www.shipsnostalgia.com/guides/images/9/91/Tryingcrossheadshoe.jpg

Jerry
Title: Re: Arnold's take on the MEM Corliss
Post by: b.lindsey on February 26, 2013, 01:29:54 AM
Nice progress Arnold. Cant wait to see one or these running.  I will be staying with the Wright engine, but have to order some materials as funds allow. I'l let them age a while...lol.  Now if i can shed some work load and get into the shop more.

Bill
Title: Re: Arnold's take on the MEM Corliss
Post by: tel on February 26, 2013, 06:58:10 AM
Quote
I'm curious.  Just what symptoms would characterize the dreaded Marv-itis. 

You break out in a rash of numbers?
Title: Re: Arnold's take on the MEM Corliss
Post by: fcheslop on February 26, 2013, 05:47:58 PM
No comment I don't have the whit or the wisdom
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on March 03, 2013, 12:01:45 AM
Thanks Frazer  :ThumbsUp: - Yes, Tipex also works; I've used that with silver soldering.  But I tend to get that all over the show  :facepalm2: .  For silver solder I now use a soft ("B" or "2B") pencil and just colour in a ring around the bits; works a treat.  I must actually try it with soft solder as well...

Quote
Arnold...I know you know I'm just having a poke at you.
I know  ;D - Here's one right back Carl; you asked for it - in many more ways than one  :stickpoke: :)

Quote
I'm curious.  Just what symptoms would characterize the dreaded Marv-itis.  Perhaps a sudden outburst of optimism* or good will?  (Believe me, if you think I'm bad now, wait until you see me cheery.)
  Hmmm... Tel got close; but judging from his current non-Ausie style head-wear he might have too many Phi's buzzing around...  To the sound of coconuts clapping, I'd say it's the ability to differentiate between European and African swallows, but then again, it might be a peculiar form of cheer around Christmas time  ;)

Bob and Jerry, thanks for those  :praise2: .  The Mery actually looks like it's a steam engine that's been converted to run as a gas engine (I'm assuming gasoline/petrol rather than natural gas) - but from the period, that fits the looks.  The double-acting Diesels are just mind-boggling; the 14 cylinder must have enough torque to winch the Moon in!  Come to think of it, the only way to make any type of double-acting engine work, one would need a cross-head...

Thanks Bill - we seem to have the same problems :facepalm2: - though I did manage to get some material this week.

Friday I managed to nip off to one of the local metal suppliers.  It wasn't quite the right day to pitch there; they were doing their financial year-end, and that's a high-stress scenario.  It's a "Local German"-run company, and anybody having anything to do with them initially might be a bit taken aback - even on a good day.  To quote James Herriot : "They're not ower cheerful Guv".  Wannabe model engineers tend to be treated as nuisances, but I've been carefully cultivating a relationship with this company; Give a cheerful greeting, try and be to the point, buy something, and don't haggle too much.  And bring along finished engines and show them what I've been doing with the bits of metal I buy from them.  They do tend to give me a lukewarm welcome nowadays ("Hello Mr. Bosch - what do you want?" from their point of view is cheerful and open-arms welcoming - I just wish they'd call me Arnold though), but on Friday the greeting was just "Look for what you need - you know where it is"... 
I was looking for a bit of steel rod to make the cylinder heads from, and also looking around for something to make the flywheel from.  A 55mm bar-end section 200mm EN8 long caught my eye for the cylinder heads - that would leave me with a good bit of stock left for other projects as well.  There were no suitable large bits of steel for the flywheel, but then a section of cast iron hollow bar caught my eye.  180mm OD x 150mm ID and 100mm long.  So with the two bits of metal in hand, back to their office.  The cashier totaled things up - N$ 476.25, and OOPS... it was quite a bit more money than I had on me.  They don't have card facilities...  So she asked me how much I had, and I emptied my wallet right there on the counter.  N$ 370 in notes, and just over N$ 10 in coins.  I think emptying my purse on the counter really amused her, because she actually cracked a smile.  She fiddled with the computer and discounts and printed me an invoice, and I came home with these:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4901.JPG)

I had quite a bit of time in the shop this afternoon, but there's not much to show for it.
I set up the steam/exhaust covers op on the lathe and skimmed one side of each down to get it flat and rid of mill scale.  There was not much to chuck up on - but it was enough to get the job done.  I also drilled a 2.5mm hole through the center (marked earlier on the mill while drilling the holes) of each workpiece at this point:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4902.JPG)

To finish the covers to thickness, I used a bit of thick cardboard between the 4-jaw chuck's jaws and the workpieces and the tailstock center to push them tight against the chuck jaws.  For the exhaust cover I just turned it down to leave a 7mm boss, as I don't intend to add much plumbing on the exhaust side:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4903.JPG)
With friction drive like this, light cuts (I do 5 thou / 0.1mm) at a time and a very sharp toolbit is needed. 

For the steam side cover, I left a bigger boss.  You might notice that the workpiece slipped a bit relative to the chuck jaws; that happened when I was machining on the boss rim and the cut got a bit heavy.  When things started slipping, I just backed off a bit, and fed back in more gently to finish off:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4904.JPG)

One luxury about normally being the only person going in my shop is that I know I can leave my machines in a "known state".  The mill and vise back-stop was still set up from last week's machining, as was the DRO, so it was a quick job to set up the steam cover again and drill out he center hole and add the flange bolt-holes which I forgot to do last weekend:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4905.JPG)

The rest of my shop session today wasn't picture-worthy, but it was good  :) .  Besides the stock I bought, I also bought a new set of M2 taps, and for the rest of the shop session, I applied those, as well as the M3 taps.  I finished tapping all the holes in the cylinder block with no drama, but it took quite a while.  It's nice when one can start mock-screwing bits together; there are studs and nuts needed though:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4907.JPG)
I'm quite disgusted with myself  :rant: .  When I drilled the holes in the cross-head flange, I was a bit off for some reason :-[ - the bolt pattern is a bit tight, so I'll have to use some judicious filing in the holes on the flange to make things match more smoothly.

That bit of cast-iron will tax my machines to the limit...  It actually fits over my 4 jaw chuck, and there might just about be enough room over the lathe-bed to machine it:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4908.JPG)
I need to cut a slice off it... After checking, that may just be possible on my "too small"' band saw.  Things might get interesting soon.  I'm promising nowt though.

Kind regards, Arnold

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: tel on March 03, 2013, 12:58:59 AM
A thin disk in the angle grinder would be my choice of weapon for taking that slice Arnold. I ran into the same thing with the flywheel for the Ridley some time back works out ok if you think ahead a bit.

Title: Re: Arnold's take on the MEM Corliss
Post by: sbwhart on March 03, 2013, 04:31:51 AM
Comming along well Arnold  :ThumbsUp:

Wathcing with interest to see what you do with that chunk of tube  :hammerbash:   :)

Stew
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on March 03, 2013, 06:47:16 AM
Hi Arnold

Always interesting to see what you've been up to during the week.  So it looks like you will be fabricating the flywheel.  Looking forward to see that when you get to it.

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: Jo on March 03, 2013, 07:10:15 AM
Arnold: I looks like you need a bigger lathe. I justified my Colchester Master to my ex because of needing to do the 12" R&B flywheels  8)

Jo
Title: Re: Arnold's take on the MEM Corliss
Post by: Jasonb on March 03, 2013, 08:07:58 AM
Arnold before you rush to cut a slice of that pipe, think about doing all the turning as you have it now then cut off and just face the other side. It will mean you can get at the face, inside and outside all without the chuck jaws getting in the way.
Title: Re: Arnold's take on the MEM Corliss
Post by: swilliams on March 03, 2013, 08:57:56 AM
That's a good story about the metal place Arnold. I was thinking that it sounded really expensive until I checked out the exchange rates. I think your German supplier is better priced than our one. Looking forward to seeing how you attack this bit of oversized cast iron.

Steve
Title: Re: Arnold's take on the MEM Corliss
Post by: steamer on March 03, 2013, 11:26:36 AM
Gotta agree with Jason...if you can pull it off.

Can you get a collet in as well as the 4 jaw?  You could mount up an arbor with a catshead at the far end ...a inch inboard of the end of the tube.

A catshead...yes it's called that....and no I didn't name it...is a block of steel mounted to a mandrel.  The block usually has 4 sides with a threaded bolt stuck in.   The hex heads of the bolt bear on the inside of the tubing perpendicular to the axis of the arbor and the arbors rotation.

By adjusting the bolts that bear on the part like an inverted 4 jaw chuck.....you can get the outboard end of the tubing to run true and be supported by the catshead and the tailstock center.

Mounted an inch in from the end of the tubing...you should have plenty of support to turn just as Jason has described.
The collet can drive the arbor, while the Headstock side of the part is driven by the 4 jaw chuck,

Dave

.....PS:....or find a buddy with a bigger lathe..... 8)

...PPS:   .....and no I haven't a clue how it got the name...but I'm sure it was an alcohol related incident.

Dave
Title: Re: Arnold's take on the MEM Corliss
Post by: Captain Jerry on March 03, 2013, 02:20:43 PM
That's a good idea, Dave.  I'm going to be facing the same problem soon so it caught my attention.  I have seen the method used before but had completely forgotten it.  Your catshead is very much like the spider that Bob (Maryak)used to handle the 8" pipe for his Scotch Boiler only he did not mount it on an arbor.  He used the four bolts like chuck jaws to grab the pipe on the inner surface and then supported it with a live center in the tailstock.  Thanks for refreshing this in my mind.  here is a link to Bob,s post on HMEM.

http://www.homemodelenginemachinist.com/f42/8-steel-scotch-boiler-16609/index3.html

Jerry
Title: Re: Arnold's take on the MEM Corliss
Post by: mklotz on March 03, 2013, 04:45:47 PM
You may find it easier to center the work on the cat's head if you use carriage bolts rather than hex head.  At least I did.

I think the name comes from the fact that the block with projecting bolts reminded some visually challenged soul of the whiskers projecting from a cat's muzzle.
Title: Re: Arnold's take on the MEM Corliss
Post by: steamer on March 03, 2013, 04:57:27 PM
Probably Marv....

Dave
Title: Re: Arnold's take on the MEM Corliss
Post by: Jo on March 03, 2013, 05:07:15 PM
Arnold,

The other way of doing it is to use your face plate and make four or six simple blocks that will enable you to put the tail of a bolt out at 90 degrees and tighten on to the inner face from the inside. Ideally with a suitable packer that will increase the clamping area on the inside of the tube and hence the stability of the mount. :ThumbsUp:.

I keep meaning to make a set of these for each of my various mills  :-\

Jo
Title: Re: Arnold's take on the MEM Corliss
Post by: Captain Jerry on March 03, 2013, 05:13:45 PM
Good point, Marv.  The round head on a carriage bolt would make fine adjustment easier, or you could dome the head of hex bolts with a file.  I would also want to use a fine thread if possible and include a jam nut to prevent creep. 

Jerry
Title: Re: Arnold's take on the MEM Corliss
Post by: Jasonb on March 03, 2013, 05:23:42 PM
I don't know if extra suppot is really needed. The bit of tube is only 100mm (4") long and you are likely to be able to get it slid back over the 6" chuck meaning the full length of the reversed jaws will be in contact with the bore, jaws are likely to be 1.5" long so that only leaves 2.5" projecting from the chuck, hardly a massive overhang.

J
Title: Re: Arnold's take on the MEM Corliss
Post by: steamer on March 03, 2013, 06:20:58 PM
Maybe.....If it were me....I'd support it....Perhaps you have more faith in 7" lathes than I...and maybe rightly so...

I have visions of a parting tool digging in big time.......

Dave
Title: Re: Arnold's take on the MEM Corliss
Post by: Jasonb on March 03, 2013, 06:36:03 PM
Dave, I was not suggesting trying to part it of but purely to turn the inside, outside and face while its easy to get at with no jaws in the way then saw/grind off the bit thats needed and then finish in the lathe.

Agree parting would be hairy even if you could get the parting tool in the right place which I doubt.

J
Title: Re: Arnold's take on the MEM Corliss
Post by: steamer on March 03, 2013, 06:39:44 PM
Fair enough Jason....

Dave
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on March 03, 2013, 08:23:12 PM
Thanks Tel.  Yes, the angle-grinder is an option...  Do you know if cast iron will harden around cuts like this? - I tend to stay away from steel that had been cut using an abrasive wheel; lost too many HSS cutting edges that way  :-\ .  I had a look, and it will be possible to use my bandsaw to saw it off too.  It's MUCH bigger than the saw is rated for, but with a clamp and some rotation during the job, it can be done... 

Cheers Stew; it will still be a while till I get to that big bit though.  I want to finish all the mountings and the base first, but the base is a bit chicken or egg - I need to know the flywheel size to finish that.

Thank you Vince; yes, I'm going to fabricate the flywheel.  That will be a whole job on it's own  ;)

Jo, the thought has crossed my mind to get a bigger lathe as well...  Fortunately I don't need to justify it to anyone, but the problem is financing the darn thing.  It took me three years to save up to buy my mill.  I had a kitty started for some other tooling and shop-related projects, but life throws one all kinds of knocks and that kitty had to go to another cause.

Jason, thanks.  I'm not rushing anywhere with that bit; it needs a good think-about.  It's _just_ too close for comfort to the lathe bed though; I think I have about 0.5mm clearance; if that much.  The last thing I want to happen is something going wrong and I end up with a ding in the lathe bed...

Thanks Steve.  From your side of the world, it might look cheap at the moment; our currency has been in a nose-dive the last year or so.  Fortunately this was old stock, so it was most likely bought in when the exchange rates were better.  Buying local, things can work out OK, but from overseas, I always have to check the exchange rates.  Sometimes I get lucky; last year when TheDROStore had their DROs on special, I happened to have the funds.  So I waited a bit and checked the exchange rates each day; fortunately at that point things were getting stronger, and when I thought it was a good time I ordered and paid.  Got it for N$ 7500 - and the very next day the exchange rate started a big slide.  If I'd hesitated there, just three days later I'd have had to pay N$ 9000 for it.  To put that difference in perspective, the Namibian monthly state pension at that point was just N$500...  Normally my overseas purchases are in US$, but on occasion, I've elected to pay in Pounds or Euros to take advantage of better exchange rates.  Funny stuff, these exchange rates  :headscratch:

Dave, thanks for the suggestions bud.  I don't have MT2 collets or a suitable collet chuck to use along with the 4-jaw, but that's not a biggy to turn up.  Don't know how often I'll use a bit of kit like that though... Hmmm, my small lathe has an MT1 spindle taper and it needs a collet chuck...  And I've got an MT2 to MT1 reducer sleeve... 
Then again, I could just shove a center in the spindle - I know that fits inside the 4-jaw.  Then use a between-centers bar to support the cat's head.   I have a nice and accurate 16mm between-centers boring bar that can do that job, so I'd only have to make the cat's head to fit to the bar. 
Unfortunately I don't have a buddy with a bigger lathe  :'( - in fact, as home shops go, I might possibly have one of the best kitted ones in the country.  I could take it to one of the local machine shops, but they'd never let me loose on their machines, so I'd have to pay commercial rates for machining I really want to do myself.  I guess I'm just a sucker for punishment  :lolb: .

Marv, good point about the carriage bolts - thank you!

 ;D I got in some more "Me" time this afternoon.
First I sawed a section off that 55mm EN8 bar I showed in the last post.  It was a bit large to chuck up with the 3-jaw chuck's inside jaws, so I switched to the outside jaws to chuck up the workpiece.  I faced of as much stock as possible using my normal left-hand cutting tool, but with the outer steps on the chuck jaws getting too close for comfort, I dug around my selection of cutting bits to look for an alternative, and couldn't find any.  So I broke out a new bit of 8mm HSS blank, and spent a couple or 10 minutes at the bench grinder and ground up an appropriate toolbit - to be mounted like a boring bar (sort-of parallel to the lathe bed - angled a couple of degrees to get the cutting tip in position). 
The original plans call for two locating pins/dowels between the cylinder head and cross-head flanges - I've ignored those and went for my own option; that is to turn a short close-fitting section on the cylinder head to match up with the bore in the cross-head to locate things.  During the design phase of the engine, I wanted to suggest this option, but I just didn't have the heart; poor Bob was getting inundated with suggestions and spent a lot of time re-drawing things.  In this photo, I've finished turning the spigot for the packing nut and the locating section:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4909.JPG)

After more turning, a bit of drilling, some boring (to get the hole to 8.75mm to tap - I don't have a drill for that) and tapping M10 x 1.25, this was the result:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4910.JPG)
I chose M10x1.25 as a "fine" thread; and because I have taps and a die for it.  It's used a lot on Japanese cars, and I happen to have these as I'm busy fitting a new engine to my old Toyota bakkie / pickup truck / ute.
The non-pleasing rings left around the bosses are there because I made slight under-cuts so that all the parts would fit together without edges fouling.  The "double" undercut around the bigger bit is pure un-excusable bad machining  :-[ - but nobody will ever see that  :LittleDevil: .  It'll do the job.

A quick trip to the mill and rotary table, and the mounting holes were drilled - just 5mm deep so as not to run into the chuck jaws:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4911.JPG)

Back to the lathe, and with the workpiece reversed in the chuck, I finished the back side to match up to the cylinder bore.  I know my 3-jaw chuck's outside jaws are pretty darn accurate - for the most part at less than 0.01mm run-out, so I was confident about just chucking up like this.  If I was in doubt, I'd have used the 4-jaw chucked up on the spigot end and clocked things up.:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4912.JPG)

The completed cylinder head:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4914.JPG)

After having a discussion with myself about those ill-fitting holes on the cross-head flange, I just drilled them out to 3.2mm from the original 3mm rather than filing each hole.  Nobody will ever know  >:D .
Now things fit together properly, and there's some stud-making on the horizon:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4915.JPG)

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: Jo on March 03, 2013, 08:28:41 PM
Wow that is coming on  :ThumbsUp:


Now things fit together properly, and there's some stud-making on the horizon:


My favourite past time, it seems to happen to almost everything I get my hands on to  :mischief:

Jo
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on March 03, 2013, 09:04:38 PM
Sheezz... Took me a fair while to post up, and in the meantime a lot of posts happened.

Thanks Jo  :) - Yes, time to break out that stainless rod.  Fortunately I checked before finally posting this message; below is what I had typed up to your previous response - before seeing your last reply... - things could be badly misconstrued, but somehow I find it amusing  :LittleDevil: :
Quote
Thanks Jo, I like your way of thinking  :ThumbsUp: , and that's been on my mind as well.  I have to check some clearances, but with the face plate I can most likely swing a ring inside of the Myford's bed gap.  In fact, that was pretty much my own initial thoughts - even if I have to make the flywheel slightly narrower to fit in the gap

Dave & Jason, you're both right.  I wasn't even considering parting off this thing; just grooving the for the hold-down clamps on the smaller diameter table for my rotary table was plenty sphincter pulling enough.  I trust my old girl, but within reason.  On this job, she's going to be asked to do things at her absolute limits, and I don't want her to get hurt, nor myself. 

I do have the mill as well, and that also holds some options along with the rotary table.  I don't see the lathe's chucks as "just for the lathe" - they are just work-holding devices.  In fact, daunting as it may seem, I have quite a lot of options of getting this job done.  I just need to play machinist's chess and think through all the different machining operations to select the most suitable one.

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on March 03, 2013, 09:22:45 PM
Hi Arnold

Great, another update and I am still stuck here in Germany turning green with envy.

If you don't mind I have a couple of questions about your last update on the cylinder head.  Please be patient with my ignorance of steam engine workings.

What you called cylinder head, is it the same as what in the plans is referred to as rear cylinder cover?  Does this go between the cylinder block and the crosshead guide?

If so, am I missing something because on the plans I cannot see any mention of threads for the rear cylinder cover whilst you tapped yours 10 x 1.25?

Thanks Arnold in advance

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: tel on March 03, 2013, 10:16:36 PM
Quote
Yes, the angle-grinder is an option...  Do you know if cast iron will harden around cuts like this? - I tend to stay away from steel that had been cut using an abrasive wheel; lost too many HSS cutting edges that way  :-\ .  I had a look, and it will be possible to use my bandsaw to saw it off too.  It's MUCH bigger than the saw is rated for, but with a clamp and some rotation during the job, it can be

It shouldn't do mate, the trick is to not be in a hurry  - mark the cut pretty accurately, then a shallow cut right around, taking your time, then follow a bit deeper, you might use up two or three disks, but that's still pretty cheap to gnaw a chunk of that. I've done similar things with the bandsaw, using it to cut stuff way over its capacity - but this bit might be too much of an ask. Where you have trouble with hardening of the cut areas usually springs from the use of those cut off or chop saws beloved of many, but I don't know if even the cast iron would harden if one was used with caution (not hanging an anvil on the pull down handle f'rinstance)

I agree with Jason in principal - machining as much as possible before cutting off could be a good thing BUT if you slide it back over the chuck body to reduce overhang how are you gonna get at the chuck keys?

Little history - many years ago (over 40) I watched a guy trim about 2' off a CI pipe about that size in the street with just a hand hacksaw and a couple of small cold chisels. Again he made a shallowish cut right around with the saw and wedged it apart with the chisels - crude? prehaps, but only needed to fit in the joining collar of a water main, so .....
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on March 03, 2013, 11:33:51 PM
Hi Vince  :)

Please do ask away; I'm as much an amateur as you are, and I'm sure our more experienced members will pitch in as necessary.

Yes, I called it cylinder head, but on steam engines it's most likely more appropriately termed cylinder cover, in this case the rear cylinder cover based on its position in the drawings..  At the risk of riling up Bob Maryak, this bit is also called the inboard cylinder head/cover.  And Yes, it goes between the cylinder block and the cross-head guide - in my last photo, you can see it sitting between those.
On the plans, there is no reference for the threads for the packing nut and threads - this was left to "builder's choice".  I chose M10x1.25 because that seemed appropriate with the finer thread, but normal M10 will work, or even M12.  And for non-metric sizes, 3/4" or even 1/2" would work.  Finer threads are better suited here, as that would make adjusting the packing nut easier, hence my choice of M10x1.25 rather than the normal M10x1.5.
I hope this helps; if not, please do ask away - it's good to get questions  :ThumbsUp:

Kind regards, Arnold

PS - What are you getting to eat in Germany Vince ? - I can highly recommend Haxenbrat und Kartoffelknudel mit sauerkraut.  - I skipped a lot of umlauts here...
 
Title: Re: Arnold's take on the MEM Corliss
Post by: tel on March 03, 2013, 11:56:26 PM
I used 3/8" x 32 ME in mine. Strictly speaking, at least in how I have always understood the terminology, that is called the 'rear cylinder cover'.
Title: Re: Arnold's take on the MEM Corliss
Post by: Maryak on March 04, 2013, 05:34:07 AM
At the risk of riling up Bob Maryak, this bit is also called the inboard cylinder head/cover.  And Yes, it goes between the cylinder block and the cross-head guide - in my last photo, you can see it sitting between those.


Takes terminology to a knew level  :facepalm: and takes more than terminology to rile me up. Only two things I hate being called and that's calling me late for pay muster or calling me too late, the liberty boat's at the gangway  :old:

Best Regards
Bob
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on March 04, 2013, 06:28:46 AM
Thanks

So that's where the gland nut goes.   :Doh:

Good thing you mentioned tapping the cylinder head because I would have missed it. :-[

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on March 04, 2013, 05:40:53 PM
Pleasure Vince, no worries  :)

I felt like a bit of machining after work today, so I stole an hour and a half out of my study time  :-X

The front cylinder cover is not a difficult bit to make, so I hacked a bit of stock off some 40mm EN8 round bar and started turning it up.  Here the boss that fits in the cylinder is done:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4916.JPG)

Before reversing the workpiece in the chuck to finish the other face and outside, I first moved the lot to the RT on the mill and drilled the mounting holes, as there would not be a lot to chuck up on, and drilling the mounting holes later could cause issues with the drill running into the chuck jaws:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4917.JPG)

Then I flipped the workpiece in the chuck, and turned the OD to size as close to the chuck jaws as I dared without actually cutting into the jaws.  To add some "visual appeal" rather than just have a flat cover, I free-hand turned an approximate dome on it:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4918.JPG)

I finished the dome with a file and then emery to get it looking a bit better:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4919.JPG)

To get rid of most of the burrs visible on the rim in the last photo, I just flipped it in the chuck again, and skimmed off the burrs.  There was still a tiny bit left; the last bits I removed with a file after removing the workpiece from the chuck.  The completed cylinder cover:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4920.JPG)

And sitting on the cylinder block:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4921.JPG)

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on March 04, 2013, 06:01:10 PM
Good idea the dome cover.  When I get to that part I might do something similar if you do not mind me copying your idea.

Hopefully tomorrow will be back home and I can continue playing with the flywheel.

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: Alan Haisley on March 04, 2013, 08:32:04 PM
Love it.
Alan
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on March 09, 2013, 07:59:52 PM
Thanks Vince  :) - you're most welcome to copy it  :ThumbsUp: .  It was a bit spur-of-the-moment, and I'm not paying too much attention to fine-scale detail on this build, as I first want to get it running and see if there were any oversights during the design phase.  There shouldn't be - the team trashed things out quite a bit behind the scenes, but building on paper/virtual reality is different from actually doing it.

Alan, thank you  :)

Today's itsy bitsy bits...

First the pack nut.  I don't have any 16mm hex stock, and I really didn't feel like making the nut from A to Z, so I used some 12mm hex brass bar for it.  The hex nut section size is not critical.
I just turned the end down to 10mm to thread, and drilled a 6.2mm hole through it deep enough to part off to.  Then I threaded it M10x1.25 using the face of the tailstock drill chuck to start the thread squarely.  Here it's ready to get parted off:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4946.JPG)

A couple of licks with a file to neaten up the hex section a bit, and it's a nice fit in the cylinder head:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4947.JPG)

The cylinder block needs some "legs" to stand on.  I don't have suitable solid material to hog them from, so these will be a fabrication.  When the engine is running, there will be fairly large lateral forces applied to them, so using soft-solder is not an option here, and I'm also a bit wary about using threaded fasteners for this job.  My stick-welding is still too much chicken-$h1t, so I'll use proper silver solder to stick the bits together. 
I cut some over-size bits of stock from a bit of 3mm plate and 60x10mm flat bar to start off with:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4948.JPG)

The 3mm plate sections were milled to size to fit the top sections of the mounting feet, and then drilled to match the mounting holes on the cylinder block.  I added the two 2mm holes along the center line - these will be used to help keep things together when silver-soldering later on:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4949.JPG)

My shop-session was interrupted at this point by the arrival of my youngest sister.  She's a tour guide, so we don't see each other that often as she's mostly on the road or working at different lodges in the country, so we spent a bit of time nattering and drinking a couple of beers.  I have a personal rule that I don't go in the shop if I've had a drink, so that's it for today.

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: Don1966 on March 09, 2013, 11:47:19 PM
Arnold that's a nice bit of work.  :ThumbsUp: enjoying it immensely.

Don
Title: Re: Arnold's take on the MEM Corliss
Post by: ozzie46 on March 10, 2013, 02:17:06 AM
Excellent rule.

Great work by the way.   :ThumbsUp: :ThumbsUp:

  Ron
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on March 10, 2013, 05:08:45 PM
Thanks for checking in Don & Ron  :praise2:

Today I started off on the two bits of bar that was shown along with the bits of plate in the second-to-last photo.  Those wire milled down to size:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4950.JPG)

An then had 2mm holes added to match those in the bits of plate:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4951.JPG)

The two blocks were still much too thick at 10mm, so I gave them a going-over with a 6mm ball nose cutter to slim them down to 6mm  while leaving the bases 10mm thick:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4952.JPG)

You might have noticed the pit-marks in the bits of plate from earlier - I don't have nice smooth 3mm plate; just a rusty old section.  I needed to clean up a bit more of it for the mounting plates - I use a rubber-backed sanding pad in the drill press for this:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4953.JPG)

Two more bits of 3mm plate ready to get machined down:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4954.JPG)

I just machined and drilled them as a pair - here the mounting holes are drilled, as well as the two obligatory 2mm locating holes:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4955.JPG)

On to rounding the corners on the bits of plate, and a bit of file-work.  I used a bit of 12mm rod, a permanent marker and the scribe to mark out the corner roundings, and set off to the vise.  I've found the easiest way to file corners like this is to first file a flat facet down to the line at about 45o :
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4957.JPG)

That is then followed by two smaller facets either side at about 22.5o and 67.5o.  These facets remove most of the material and forms a good approximation of a curve:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4958.JPG)
Then I use a finer file and follow the "curve" from the flat ends while stroking - this removes all the high edges left by the facets first, and with just a couple of strokes the corners are rounded.  I forgot to take a photo of this  :-[ - but you'll see the results in later photos.

I used a bit of bronze brazing rod to pin the parts together after adding flux in between all the bits and then clamped them together with a toolmaker's clamp.  Then I threw the Sievert torch at them with its 20mm nozzle - this makes a lot of heat very quickly - and heated the lot up to dull red.  When the flux flowed, I added some naughty cadmium-bearing silver solder from a stick and this flowed nicely into the joints.  The flame from the Sievert do tend to make things go horribly black from oxidization, so I made a "very quick" pickle - a table spoon of citric acid in 250ml of boiling water - and dunked the two bits in there to pickle off a bit:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4959.JPG)
Unlike other acids, the little citric acid spill is nothing to be worried about; one simply wipes it up with a bit of paper, but I do the pickling outside the workshop (here it was done on the steps outside the door), as the fumes will make any un-oiled metals rust like mad.

After 10 minutes in the pickle, and I could see the results - some slight spillage of silver solder, but not nearly as much as I've had in the past, and nice fillets all-round all the joints.  As I'd only applied the silver solder from one side, this confirmed good penetration:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4960.JPG)

As a final step, I milled the cut-outs for the exhaust chest cover:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4961.JPG)

The two mounting feet pretty much done:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4962.JPG)

Slowly coming together - a bit at a time:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4964.JPG)

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on March 10, 2013, 11:25:45 PM
Arnold

You are really moving along at a fast pace.  In a short time you will have reached the flywheel stage and I would still be hacking at it.  As Tel said, the flywheel is a project on its own.

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: swilliams on March 11, 2013, 12:34:44 AM
Yes - nice progress Arnold. I'm also an old friend of the rust pitted stock  :agree:

Steve

Title: Re: Arnold's take on the MEM Corliss
Post by: b.lindsey on March 11, 2013, 01:04:28 AM
I look forward to your updates Arnold, its coming right along and should make a beautiful engine when complete.

Bill
Title: Re: Arnold's take on the MEM Corliss
Post by: Captain Jerry on March 11, 2013, 02:41:36 AM
Nicely done and rock solid.

The cylinder block needs some "legs" to stand on.  I don't have suitable solid material to hog them from, so these will be a fabrication.  When the engine is running, there will be fairly large lateral forces applied to them, so using soft-solder is not an option here, and I'm also a bit wary about using threaded fasteners for this job.  My stick-welding is still too much chicken-$h1t, so I'll use proper silver solder to stick the bits together. 

 Arnold

This statement made me wonder.  I thought they were just to support the weight and that the thrust would be taken up by the frame.  Many engines just cantilever the cylinder to the frame with no legs.  The web has many pictures of Corliss engines being moved for restoration and the entire engine is being lifted as a single unit.  So I got looking at the plans a little closer.  Either I am missing something or this design is very different.  I don't see that the outboard end of the trunk guide is fastened to the frame.  It just seems to be a close fit with no fasteners.  Is it meant to be held with adhesive or solder or is it intended to be left loose?  Locktite might be a little iffy but solder would seem to be enough to take the thrust.  If is is left loose, that would allow for adjusting the alignment but that would mean that the cylinder supports have to take the lateral force as you say.   What was the thinking for doing it this way?  Just curious. 

Jerry
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on March 17, 2013, 07:08:06 PM
Thanks Vince  :) - Yes, the flywheel will be quite a big project - it will push my skills and machines to the limit  :agree:

Steve, thanks  :) - There's some more of the pitted stock in today's post.  One's got to use what one has to use  :Lol:

 :) Thank you Bill.  Its slowly starting to get to the point where I have to start thinking of the paint job and colour...

Thank you Jerry  :) .  During the design phase we didn't discuss the cross-head guide to crank-frame joint a lot.  From the plans, it is a slip fit as you say - and actually I prefer it that way, as it will make the engine a bit easier to assemble and disassemble when it comes time to getting it to run and painting it.
You're quite correct in that these bits would be solid on full-size engines.  I don't see the slip fit as much use for adjusting things, other than allowing a bit of leeway for mounting.  Adjustment would be done through the piston rod and connecting rod.  I did consider adding some grub screws (set screws) to the mix, but that would add unsightly holes.  Screws and/or soft solder might be fine to build up the cylinder mountings, but after having machined them, I don't think that's a safe option unless one machines very lightly indeed.  Machined from solid, there shouldn't be any problems.

Yesterday I spent  :happyreader: and  :killcomputer: - it got to a point where I realized my desktop PC and laptop combined can't handle the number of virtual servers I need to carry on my studies, so I need to go spendybigbucks on a seriously powerful computer this coming week.  Dammit... Tool and stock money down the drain  :toilet_claw:

This morning I took the rotary saw my grandfather passed on to me two years ago outside the shop.  It's a nice and powerful machine, and came with a small mounting stand.  I proceeded to cut up some bits of teak:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4966.JPG)
Outside the shop's nice for this - no wood dust in the shop, and a light breeze will return the dust to mother nature  :) - or one of the backyard neighbours' houses much to the chagrin of the housewives.  I'll be sure to keep my house windows closed  :LittleDevil:

I haven't used my wood plane in a long time, and the last time I did, it was very blunt.  This teak is quite tough to work with, so I spent a good 20 minutes on the oilstone re-sharpening the plane's blade, and then put in some elbow grease to plane up the bits of wood on the cut edges with very fine cuts:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4967.JPG)
A longer plane would be better for this job, but this is my one-and-only, so it had to do.

Some wood glue, and a "cabinet maker's" bit of work with clamps - I've never ever tried this, so I'm holding thumbs:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4968.JPG)
This side of the planks was left in the weather, so it looks really dark and messy; the other side looks better.

On to metal again, and I hacked a couple of bits from some 12mm plate - as well as some more of the pitted 3mm plate.  12mm plate for the cross-head guide support is a bit thin; that should be 13.5mm according to the plans, but I didn't have anything suitable on-hand, so 12mm will have to do.  And yes, this will be another fabrication:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4969.JPG)

Off to the mill, machined to size, and the one end with the sticky-outy-bit (Zee terminology) for mounting the bearing on machined:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4970.JPG)

Some more machining with a 16mm end mill and I really hogged things out - this end mill isn't exactly the sharpest tool in the shed any more, but still gets the job done with a bit of heavy-handed machining.  I intentionally left the steps at the ends of the cuts:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4971.JPG)

With the workpiece re-mounted flat in the mill vise, I finished off the last bits.  The steps I left earlier roughly approximated the curves needed to finish off the cut-out with a 12mm end mill running at full depth:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4972.JPG)

I stopped there for today, but put together a couple of "family" photos:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4974.JPG)

(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4975.JPG)

Seeing as this is St Patric's day, a grumbly deep-pocketed old leprechaun decided to make fun of me, and made the prepaid electricity meter run out of pre-paid just when I was about to post - so this was a complete re-type of my post.  So here's one on the little green men  :DrinkPint: and a happy St Paddies to all involved  :cheers:

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: steamer on March 17, 2013, 07:29:18 PM
That's Sweet Arnold!

Dave
Title: Re: Arnold's take on the MEM Corliss
Post by: Bearcar1 on March 17, 2013, 08:24:35 PM
AH yes, those irish laddies leprechauns, they can be a might capricious at time they can. Especially during the Celebration of Eire.  :DrinkPint:  Things are shaping up very well indeed Arnold, and your work is once again to a high standard. Just a note about working Teak wood in case you, or anyone else for that matter that does not usually work with the stuff. Teak is an oily wood that lends itself to marine usage quite well due to this fact. It has and is used for the pass-through stuffer boxes for the propellor shafts on some vessels in fact. Anyway, the best procedure to follow when gluing the stuff up is to do so as quickly as possible after cutting and having a close fitting joint. Now here is the *trick* for a truly good joint, wipe the surfaces to be joined down with a clean rag that has been doused in denatured alcohol or acetone. This removes the surface oils and to some extent dries the wood out and allows for the glue to better penetrate. The wood will naturally replenish itself, but the glue will by that time have done its job. This is practice is probably not necessary for your application as the joint will be exposed to minimal if any stresses, but I just thought that I would toss about one of Mr. Hulvey's (HS woodshop instructor) teachings.


The Captain brought up a point I was wondering about as well on the frame not being a solid piece as in full scale practice but am laying back in the weeds and watching how this will unfold. Obviously the stresses exerted on that area will not be tremendous but I still wonder about it. Just me :insane: :Doh: (is this emoticon politically correct?) well no but  :slap: ..........  :help:




BC1
Jim
Title: Re: Arnold's take on the MEM Corliss
Post by: tel on March 17, 2013, 08:43:32 PM
Quote
  I'll be sure to keep my house windows closed  :LittleDevil:

So you can't hear the complaints? Good thinking!  :ThumbsUp:
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on March 17, 2013, 09:00:55 PM
It's really coming along nicely.

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: gbritnell on March 17, 2013, 09:45:33 PM
You're making excellent progress Arnold.
gbritnell
Title: Re: Arnold's take on the MEM Corliss
Post by: Don1966 on March 17, 2013, 09:59:06 PM
She's looking good to me Arnold. Great job as usual. Still following with great interest.

Don
Title: Re: Arnold's take on the MEM Corliss
Post by: zeeprogrammer on March 17, 2013, 10:05:21 PM
Nice work on the 'sticky-out-bit' Arnold.  ;D
Title: Re: Arnold's take on the MEM Corliss
Post by: Maryak on March 17, 2013, 11:14:38 PM
Arnold,

Very nice  :NotWorthy: I hope your studies are progressing with the same level of success.

Best Regards
Bob
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on March 21, 2013, 04:30:25 PM
Thanks for checking in everyone  :praise2:

Jim, those are nice tips on gluing Teak - I didn't know that - Thank you!  I'll see how things pan out with the "loose" joint - it does mean that there will be separate stresses on the cylinder and the flywheel mountings, and the base and mounting bolts have to take these...  If there are problems, I'll Loctite or solder the loose joint.

Bob, the studies are going well thanks.  I'm waiting for my new PC to be delivered, so most of it is at a standstill right now.

Fortunately, with the studies at a standstill and a public holiday here in Namibia today, I got a bit of shop time  ;D

First the one block of steel from the last post was milled to size, then, after a bit of marking out and a whack with a punch for the center of the hole, was clocked up in the 4-jaw and drilled out to 19mm:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4977.JPG)

Next, bored out to a close 27mm to match the cross-head guide:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4978.JPG)

Off to the mill, and I milled out the step needed:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4979.JPG)

To round it over, I used the cross-head guide as support and milled off the excess in facets:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4980.JPG)

Milling complete:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4981.JPG)

I put in a bit of effort with a couple of files, and soon the facets were gone and the bit is nicely rounded over:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4982.JPG)

After that I milled, drilled and filed the bits of 3mm plate to size and shape and rounded all the necessary corners.
The long block of steel with the sticky-out-bit still needed some holes drilled into it as well.
I set of, and immediately made a stuff-up  :facepalm2: - even though I used the edge finder to locate all the needed dimensions, I forgot to center back up on Y after I found the right hand edge and dialed in the offset for the hole:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4983.JPG)

Rather than re-making the workpiece, I used a 3mm end mill to open up the hole at the correct location.  This won't be visible, so for now I'll call it "character":
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4984.JPG)

A 2.5mm hole was drilled 18mm further in from the edge - this time on the center line.  This will later be tapped M3.  As a last step, I drilled a 6mm hole right on the bottom edge of the workpiece.  This is to receive a bit of 6mm rod that will be drilled and tapped to mount the lever that links the valve rods:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4985.JPG)

A photo of the bits as I stopped today.  The closest vertical edge in the photo next to the valve lever hole still needs a bit of rounding over, and I have to make the bit where the valve lever will be mounted - then I can solder the lot together:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4986.JPG)

Much to my surprise, everything fits really well together when assembled on a flat surface - with none of the mountings too high or too low - I'm really happy with that  :):
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4987.JPG)

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on March 21, 2013, 04:35:43 PM
Nicely done Arnold.

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: Jo on March 21, 2013, 05:34:52 PM
You are making some really good progress there Arnold.  :ThumbsUp:

Jo
Title: Re: Arnold's take on the MEM Corliss
Post by: metalmudler on March 21, 2013, 06:17:20 PM
Hi Arnold,
You definately dont know me. I would like to thank you for taking the time to upload your pics,this is something i lack the time for.Im Shit with words,but pictures tell 1000 words.I hope to be uploading some of my stuff soon. Your stuff is good m8 ;)
Title: Re: Arnold's take on the MEM Corliss
Post by: Don1966 on March 21, 2013, 11:53:29 PM
Hi Arnold, it's looking good and I do Like the way you used the guide truck to mill the mounting flange.  :ThumbsUp: Great work as usual.

Don
Title: Re: Arnold's take on the MEM Corliss
Post by: zeeprogrammer on March 22, 2013, 12:52:40 AM
Very nice file work Arnold.
And always an interesting post.
Title: Re: Arnold's take on the MEM Corliss
Post by: Captain Jerry on March 22, 2013, 01:07:00 AM
Nice work, Arnold.  Looks like a very solid fabrication.

Jerry
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on March 23, 2013, 07:04:03 PM
Thanks all for checking in  :praise2:

Paul, yes, I don't know you, but I did read your Intro (I read each and every single post here on MEM).  I've not been as diligent as I should be about welcoming our new members  :-[ .
Pictures may be worth a thousand words, but a couple of words can make a picture worth even more.  Don't be afraid to use words - it works much like learning to use tools; the more you use them the more comfortable you get about using them.  Looking forward to your posts mate  :ThumbsUp:

Well, my new PC is still a no-show, so I guess I've got most of the weekend for machining  :)

First up some file-work; I just rounded over the end of the long bit by eye.  It's not critical, and just for looks, so if it looks good enough it is good enough:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4988.JPG)

Then I started to solder the bits together.  First the cross-head guide carrier to the long section - making sure that they were nice and square (no photo) then the foot at the end of the long section:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4989.JPG)

When I silver soldered the cylinder mountings, I used the Sievert propane torch, but found that even though it gave a lot of heat fairly quickly, it didn't work as nice on the steel as it does on copper and bronze.  So I used the oxy-propane kit; this makes a much hotter, but smaller flame, but with the steel not conducting away localised heat as quickly as copper, it was easy to get the joint areas heated up very quickly to soldering temperature - and a dab with the solder stick on the opposite side of the joint after the flux ran and the metal on that side was dull red made the solder wick right into the joint toward the flame side.  I found this much more controllable - though I still did make a bit of a mess in some spots  :Lol:

I nearly forgot about the valve lever mounting - fortunately I had not soldered the "larger" base plate on yet.  I turned up the mounting from some steel, and drilled it to tap M3.  The plans says M2.5, but I still don't have M2.5 taps, and the one set I've been able to find costs N$400 - that's a bit dear right now...  M2 seems a bit light-weight for this link, and there is enough room to use M3.  I didn't tap the hole yet; M3 threads are quite delicate, and between oxidisation from the heat while silver soldering and pickling afterward, they might just be eaten away:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4990.JPG)

The pivot pin installed in the workpiece - I removed the oxides from the previous silver soldering session in the hole by first twirling a 6mm drill bit in the hole, and then rubbing off the rest with a bit of rolled-up scotch-brite:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4991.JPG)

Next I cleaned up the bottom of the workpiece with scotch-brite as well to get rid of the crud there, dropped some flux and a 1mm long bit of snipped-off silver solder in the pivot mounting hole before inserting the pivot mounting, and lastly added some flux between the upper bit and the mounting plate.  I set the lot up on the flattest bit of fire-brick I have, and gave it the welly with the torch, once again heating from one side and feeding the stick from the other side once the flux flowed and the bits of metal around the joint was dull-red.  After cooling a bit, it looked like this:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4992.JPG)

I'm slowly growing more confident with silver soldering - things still are not as nice-looking as other members show, but each time I learn something new.  How to maneuver the torch.  Where to apply the heat.  When to start applying solder.  How much flux to use.  How much solder to use.  I'm still getting a lot of that wrong, but it is improving.  I still tend to apply too much flux and solder - though I think for today's session, I got the flux proportions better.  Still too much solder though.  And to put that in perspective, I used only about 10mm of 1.6mm solder rod in total today...  More practice needed  ;) .  Another scary bit about silver soldering is the way the workpiece looks once done.  It's always that "Darn - how will that lot EVER clean up" feeling.  I still get that feeling, and the photo above shows why...

Off to the kitchen, and I purloined a suitable plastic container from the kitchen cupboards.  While I was there, I filled the kettle and put it on to boil.  The kettle takes about 1.75l of water, but I stole enough to make a cup of coffee before pouring the rest in the plastic container and adding about a table-spoon full of citric acid to that.  Taking the coffee and the acid tub to the shop, I plonked the workpiece in the hot citric acid (outside on the shop step) , and it immediately started to fizz up in there:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4993.JPG)

Once the coffee was finished, I took the workpiece out, gave all the still-black bits a scrub with a small stainless-steel wire brush, and plonked it back in the pickle.  That was right about lunch-time, and as I was feeling a bit peckish, I went indoors and had a nice ham and cheese sandwich in front of the telly with the AC on to cool down.  Happened to watch a guy called "Guy" eating grits and sausage sauce on the Food channel  :-X :paranoia:

Back to the shop, and I rinsed the workpiece very thoroughly with clean water.  A good scrub-down with more scotch-brite, and it looks OK - except for where I applied too much solder:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4994.JPG)

On to some work on the base.  When I planed down the sides of the planks that I glued together for the base, I didn't get them entirely square, so the glued base ended up with a slight rise in the middle.  The last time I tried to plane a flat sheet of wood down was back in my junior high school days - about 1996...  And that was in a well-fitted woodworking shop...  Well, I have what I have, so I soldiered on - clamping the plank in different orientations and just manually planing it down:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4995.JPG)

Once it looked about flat enough, I took the orbital sander to it - outside again.  Things turned out surprisingly well  :) :
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4996.JPG)
 :o There's quite a large difference in the wood colour between inside the shop under fluorescent lighting and outside in natural light when photographed!

All the sides were still pretty rough, and there was no convenient or safe way to run those past the circular saw in it's stand, so I took it out of the stand, set up some trestles outside (under the car-port - so nice and shaded) and started trimming away:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_4997.JPG)

The underside of the plank is still very rough, and I'll need to make a plan with that.  The circular saw blade is no longer in prime condition, and I have no way to sharpen it yet, so it hacked some corners off the wood, but that I'll fix with a router and an edge-shaping bit later on.

A family shot with all the bits in their approximate locations:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5000.JPG)
 :) And Yes! - they all sit flat and fit together  :whoohoo: - even on the wood!

There's lots of flaws for everyone to see in the overall picture, but somehow I don't mind that.  This project has been a lot of hard work so far, and for the most part have taxed my own machining abilities to the limit with working in steel rather than non-ferrous metals, making built-up assemblies and even the wood-working.  I'mHavingAHellOfALotOfFun  ;D

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: Jo on March 23, 2013, 07:20:35 PM
Arnold,

One of the reasons you were having problems silver soldering is that the piece you were working on is out in the open, so it has lots of opportunity to radiate its heat away. Try adding a couple of bricks close behind the work or even a couple of bits of scrap metal. Ok they will warm up but they will radiate the heat back towards the work  :ThumbsUp:.

And you might want to invest in some of the really thin silver solder, its really good for making little rings out of and putting around the joints you are trying to make.  ;).

Jo
Title: Re: Arnold's take on the MEM Corliss
Post by: Alan Haisley on March 23, 2013, 08:30:16 PM
There's lots of flaws for everyone to see in the overall picture, but somehow I don't mind that.  This project has been a lot of hard work so far, and for the most part have taxed my own machining abilities to the limit with working in steel rather than non-ferrous metals, making built-up assemblies and even the wood-working.  I'mHavingAHellOfALotOfFun  ;D
Me too! It's great watching the problem solving.  :cartwheel:
Alan
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on March 23, 2013, 11:16:19 PM
Quote
There's lots of flaws for everyone to see in the overall picture, but somehow I don't mind that.

Arnold, I can't see any and if there are any they are well hidden. :cheers:

I suppose fabricating the guide and crankshaft support is the best way to go.  I cannot imagine myself hogging it out from solid.

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: Don1966 on March 23, 2013, 11:49:41 PM
Looking good to me also Arnold, I see no flaws. Always a pleasure to see more progress.

Don
Title: Re: Arnold's take on the MEM Corliss
Post by: swilliams on March 24, 2013, 11:16:59 AM
Looking great Arnold, Shaping up to be a really great engine  :D

Steve
Title: Re: Arnold's take on the MEM Corliss
Post by: b.lindsey on March 24, 2013, 12:55:13 PM
Arnold, you are making great progress on several fronts and its nice to see your updates.

Bill
Title: Re: Arnold's take on the MEM Corliss
Post by: Bearcar1 on March 24, 2013, 03:53:51 PM
No flaws, just a great deal of character. Nicely done  :ThumbsUp:  It seems almost a shame to cover up such a beautiful piece of the brown stuff (Naaaaaaaaah) Thinking ahead, do you have any plans for paint or just polished metal? (the engine of course) This is going to be one handsome beast when you are finished.  :Love:


regards


BC1
Jim
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on March 24, 2013, 04:26:04 PM
Thank you all who checked in  :praise2:

Jo I forgot all about the reflective brick(s)  :embarassed: .  And yes, I need to get some thin solder wire; that's unobtainable locally or from South Africa, so I'll most likely have to order it in from the UK.  Some solder paste as well for the really small jobs.  My flux is a really coarse powder, and even if mixed with water it stays very granular.  I wonder if pounding it finer with a pestle & mortar would work...

Vince, I'm pretty sure it can be hogged from solid, but it would be a huge waste of material, and could take quite a bit of time to do.

Jim, a lot of that wood will remain visible; I must admit I have a soft spot for teak  :) .  Rather than wax it like I normally do with teak, I'll varnish it this time.  Oil droplets do get into the wood and stain it if it's just waxed. 
All the steel bits will be painted, that's why I haven't bothered too much about getting very good finishes.  I'm still debating the colour with myself...  I think my favourite dark blue would be a bit on the "heavy" side on this larger model, so right now I'm thinking about a lighter blue.  I think it might also look very good in light burgundy or ruby, but seeing as it will eventually make it's way to my living room, that would not match anything in there, and will stand out like a sore thumb  :Lol:

Not much of an update for today - I just made the outrigger bearing pedestal.

A block of steel - accurately sized to 33x24x12mm, and milling the cut-outs:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5001.JPG)

Then I drilled the 3mm mounting holes:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5002.JPG)

A quick lick with a file on the bottom section to round over the corners, and the job was done:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5003.JPG)

The vise back-stop came in really handy today as this is a symmetrical part, so once set up, it was just a matter of flipping the part around to carry on operations on the other side.

Not much progress then, but every part made is a part made  :) .  I had a look at the bearings themselves - I'll divert slightly from the plans for those, and make them from steel with phosphor bronze bushes, rather than all-bronze.

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on March 24, 2013, 04:54:09 PM
Arnold

I was thinking also about the crankshaft bearings and my idea was to make both of them at the same time (from one piece) and then split them with a slitting saw.  Problem is that I cannot find phosphor bronze in square section.  Sometimes I think it is only available in round section.  What if I use brass (which is available in square section) for the bearings?  Is it too soft for this application?

Also, I was thinking of making an oil cup for each bearing.

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on March 24, 2013, 05:45:59 PM
Vince, I only have access to phosphor bronze in round as well, that's why I'm going with the bushings in steel housings. 

Brass should work just as well; it's quite a good bearing metal if you make your crank shaft with steel or stainless steel.  I doubt if any of our engines will see heavy or long periods of use, so brass bearings should last it a lifetime.

The oil cups are a good idea  :ThumbsUp: - in fact, I was also thinking about adding some; it will add a nice bit of detail to the engine.

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: Captain Jerry on March 25, 2013, 01:55:34 PM
I have used brass where appearance is important and I have use oillite bushings for quick but I have also used cast iron bushings.  The cast iron seems to give a nice smooth bearing with very low friction.   Is there any problem with cast iron for these low speed, low power, low hour applications?

Jerry
Title: Arnold's take on the MEM Corliss
Post by: NickG on March 25, 2013, 04:35:30 PM
Can't see a problem with cast iron, it's self lubricating properties should make it good, bit like Phos bronze or oilite.
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on March 25, 2013, 05:42:41 PM
Hi Jerry

Like Nick said, I think the cast iron is good to go  :ThumbsUp: - with steel shafts it gives about the same coefficient of friction as sintered bronze on steel, and better than brass on steel (there's a list here (http://www.engineeringtoolbox.com/friction-coefficients-d_778.html))

Both my lathe and mill use steel gibs on cast-iron slideways, and if it's good enough for machines, it's definitely good enough for our small low-use low-power toys.

About the only of the small engines where it matters more is with hot air or Stirling types, where one needs to overcome every single bit of friction as much as possible.  And even having said that, my Phil Duclos "Little Blazer" fire eater runs like a champ with a silver steel crankshaft in aluminium bearings, with just graphite powder for lubrication, and this is my most-often run engine with about 50 hours of total run-time on it.  I know Marv built his one with the aluminium cylinder and piston, and as far as I'm aware his is also still running fine - and most likely has a LOT more run-time on it...

So in my humble opinion, for our hobby model purposes, pretty much anything goes in general.  I have no clue about Internal Combustion engines, so that may be another matter, especially for diesel types.  With live steam, the cylinder and piston materials do make a difference, but that's more related to heat expansion and corrosion rather than friction.  Others may disagree, so keep an open mind.

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on March 30, 2013, 04:10:51 PM
Well, my new PC arrived on Thursday, and yesterday I spent setting it up properly and loading all sorts of software on it to carry on with my studies.  This being a 4-day long-weekend here in Namibia, I'd decided to spend two days studying and as much as possible of the other two in the shop.  There's some domestic matters that also need attention  ::)

Today's shop session started with two blocks of 12mm plate - already milled to 18mm width before sawing them apart:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5015.JPG)

A quick job milling them to length on the mill:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5016.JPG)

Then I drilled 10mm holes through them for the bushes, after using the edge finder to locate the centers and also setting up the vise back-stop for the rest of the operations:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5017.JPG)

I used the jungle-formula from that Potatograss feller that insists on sticking a square on a hippopotamus to calculate where the flats on the bearing caps would intersect with the curved section when using a 6mm end mill to make the flats - makes machining a bit easier later on:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5019.JPG)

Then I drilled the mounting holes, and milled the flats out to depth and the calculated offsets:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5020.JPG)

The 6mm clearance arcs around the mounting holes was too little, so I enlarged that to 8mm by centering up over each hole and just plunging an 8mm end mill down to meet up with the flats after this photo was taken - you can see the rings it created on the flats in this photo where I'm setting up to round over the tops of the blocks:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5021.JPG)

Rounding over - here's one side just about done.  I was my normal lazybones self and did both workpieces at the same time:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5022.JPG)

The other side done:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5023.JPG)

After a bit of filing:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5024.JPG)

On to the lathe for a change, and I started turning some 12mm phosphor bronze down for the bushes.  PB can be a pain to turn sometimes, but today I think I got something right, as I got a very nice finish with no effort at all:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5025.JPG)

The finished bushes - turned for a light press fit in the bearing caps, and only drilled through at 7.8mm for reaming to 8mm later on:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5026.JPG)

I pressed the bushes into the bearing caps with a dab of bearing retainer smeared around the "coarse" finish left by the drill in the bearing caps - a little belt-and-braces measure, as I need to finish the reaming later on.  Then I snapped the latest "progress overview" photo:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5027.JPG)

Kind regards, Arnold




Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on March 30, 2013, 04:52:19 PM
Hi Arnold

Another two pieces of your engine finished.  Thanks for the detailed descriptions of how you do things.  Love them.

I am still carving out the spokes of the flywheel very, very slowly.

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on April 01, 2013, 07:41:49 PM
Thanks Vince  :) .  Carving out that lot will be a bit tedious - I've only done much smaller flywheels from solid, and that took a lot of concentration...

I wanted to make a start on the valve covers today.  I thought I had a long enough section of 16mm square brass to turn up the inside covers, but obviously I thought wrong.  So I fell for my own April Fool's joke and spent a couple of minutes setting up the dividing head on the mill to make up some 15mm square bar from 16mm round rod I have quite a bit of... 
...
...
16mm round cannot be milled to make 15mm square  :facepalm2: .  Yes, you are allowed to laugh at me  :) .
Nothing else I have in stock would work without enormous wastage, so I'll try and nip into the metal candy-store this week and dig around for something suitable; it's close to my barber and the couple of hair left on my noggin needs a trim as well - both these haunts are on the other side of town from my normal area of operation.

I grabbed a bit of really crappy 32mm steel and started to turn up the valve disk hub, determined to get a good finish from this steel for a change.  After roughing it close to size, I took a couple of minutes and honed up my HSS cutting bit to a really sharp and smooth cutting edge on an oilstone.  To try and keep that edge while turning, I slowed the lathe down to it's lowest non back-gear speed.  With a fine depth of cut and slow feed, I got the best finish ever in this cruddy steel  :cartwheel: - with a bunch of very fine steel wool forming on the lathe tip along the way:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5030.JPG)
 ::) OK, it may not seem like much - I get better finishes easily on silver steel and even stainless with much less effort, but its a personal thing.  I have a LOT of this specific steel and have never been very successful turning it, so it's a good step in the right direction to use what I have, as well as some more valuable machining lessons learnt.

A quick trip to the band saw had the tuned bit sawed off slightly over length, then I mounted it in a collet to start on the rest of the steps.  I chucked it with the flange out about 2mm from the closer nut face - the reason for this will become apparent later.  After facing the flange down to 1.5mm thickness, I drilled (4.9mm) and reamed through the workpiece with a 5mm reamer:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5031.JPG)

I drilled a 5.5mm hole to near-depth through that, and followed it with an 8.5mm drill 4mm deep.  The inside of this workpiece serves as a bearing pivot for the valve plate, so good finishes are essential - drills don't give these.  Following the exact diameters to plan is also not that important. Close enough is good enough - it's easier to compensate for differences in size when making the matching valve disk spindle, but the final match between the two parts must be very smooth and light with an absolute minimum of play, otherwise the valve disk will wobble causing binding in all the valve linkages.  Boring to the correct depths can be a pain, so I set up my bed-mounted dial indicator for a bit of help:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5032.JPG)

The smallest boring bar I have is one ground from some square 4mm HSS - I honed that up really well, and started boring the stepped internal diameters:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5033.JPG)

Once those were done, I moved the chuck to the rotary table.  The reason I left the gap between the flange and the collet closer nut was so that I could drill the mounting holes without drilling into the closer nut (or collet):
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5034.JPG)
While drilling, I also inserted a bit of 0.5mm brass shim stock in the gap between the flange and the closer nut - even if the drill grabbed a bit when breaking through, this would save dings on my work-holding equipment.

On to the valve disk spindle, and I turned it to a close match to the valve disk hub from phosphor bronze - just testing the fit along the way and taking off imaginary 1/4 thou in-feeds in the final stages on the cross slide by reading the dial between the lines.  A very sharp toolbit is essential for this.  If you think you're seeing a bit of a hollow on the middle step, you are correct.  The corner to the next bigger step was not quite sharp enough because of the tool radius, so I used the rear parting tool to edge into the corner, but slightly over-did it  :-[ - hence the hollow.  The rest of the section is spot-on and will function as expected.  You'll also notice I added some generous chamfers to the sharp edges - this should prevent binding in the corners of the valve disk hub:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5036.JPG)

Back to the mill and rotary table, and I milled the needed square section on the spindle:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5037.JPG)

Off to the lathe again, and after parting off the spindle, I ended up with today's bits for shop time:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5038.JPG)

Where they fit together on the cylinder block:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5039.JPG)
Also visible is the reason I asked about paint in the "20 Questions" thread - we've had a terribly dry spell so far, but the last two days the rain came belting down and immediately there's rust on the block and mountings, so I need to get some paint on there soon, or oil it up and have to remove the oil later...

Another very interesting thing I noticed in the shop - or maybe it's my imagination.  On Saturday when I worked in the shop, it was still well into the 30oC temperatures here, and today it was just 20oC - and all the machines felt tighter to operate.   Is it just me getting old bones, or can a 15oC change in temperature make such a difference in the feel of the machines?

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: b.lindsey on April 01, 2013, 08:23:15 PM
Arnold, the progress overview shots are looking really nice....its starting to take shape...thanks for the update.

Bill
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on April 01, 2013, 10:25:38 PM
Thanks for the update Arnold.  It will be interesting to see how you will make the square hole in the valve disk.

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: Don1966 on April 01, 2013, 11:16:58 PM
I am really enjoying your progress Arnold. Some superb work as usual and she's shaping up great. Your photos are top guiltily also.

Don
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on April 07, 2013, 05:19:00 PM
Bill, Vince & Don, thanks Gents  :praise2:

Not much progress to report...  Today was all about butchering - earlier this week a sheep and an oryx walked into my freezer, so those had to be taken care of...

Then I managed to fit in a bit of shop time, and the butchering continued; not some of my best work - on the valve disk.  It's dimensionally correct, but does not look too good, so I might have to re-make it later, taking a bit more time to make it look better.  For now it'll do - I'd like to get the valves and linkages going, as this is an area where there could be a couple of unforeseen problems.

I sawed and milled a bit of 3mm plate to size for the valve disk, and located edges to zero up the DRO on the center of the square hole. Then I started spotting hole locations - the exact center of the square hole, as well as four positions offset 1mm in both X and Y.  I'd decided to use a 1mm drill to get into the corners of the square section for a start:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5042.JPG)
Nearly made a booboo with the calculations there; You might see two additional spot marks offset by just 0.5mm...  The funny little man in my tummy kept screaming at me that something wasn't right, so I stopped, thought, and realized the error before spotting in the correct locations.

While I was busy spotting hole locations, I did the rest as well:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5043.JPG)
The locations where the disk arms will mount are on a 33mm PCD, but not at a convenient angular spacing to use the DRO's PCD function, so I just used a quick bit of trigonometry to calculate their proper X and Y locations.

Then drilling started.  Unfortunately I skipped taking a photo here, and I know Vince is interested in this bit, so I'll describe.  I drilled 1mm holes through the spotted corner locations for the square hole, as well as through the center. 
Then I drilled through the center location again with a 2.5mm drill - hoping that the center 1mm hole would tend to guide the drill and prevent it deflecting.  This seems to have worked, and the drill deflected only a tiny bit when it broke through - this time there is a photo of the result:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5044.JPG)
It's slightly deceptive - the 2.5mm drill left burrs in the 1mm corner holes but went through nicely on center.

Some more holes drilled - this time 1.4mm and tapped 10BA.  This is the area in which the size of the engine was determined to an extent - being the smallest fasteners that will be used.  Note that on the plans these are not shown as tapped holes, but I think they should be, as they will be used to mount pivots for the disk arms.:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5046.JPG)

As a last step, I plunged a 3mm end mill through the "square" hole to get rid of more material.  I could have done this earlier, but all the previous work needed the small drill chuck to do, and for this I had to switch collets.  Just me being lazy.:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5047.JPG)

Off to the big bench vise, and a small triangular needle file and a couple of strokes later, the hole was square.  I used the triangular file, as it's easier to file out sharp corners for me with it than with a rectangular file - which still tends to make rounded corners.  This was my smallest needle file, but it was still too big for the hole, so I only had about 25mm of usable travel on it.  I just carefully worked my way around the hole filing away the same amount on each face and testing regularly with the spindle for a fit:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5048.JPG)

And ended up with a nice snug fit - with no free play at all:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5049.JPG)

Back to the milling machine, and some more trimming:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5051.JPG)

Once again back to the bench vise, and this is where the butchering started.  Got a couple of bits too close while hacksawing out the excess:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5052.JPG)

And further butchering - instead of making up some filing buttons, I eyeballed things for filing to shape, and in a place or two took away too much metal...  The results:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5053.JPG)
Like I said - not very good to look at - but adequate for now - all the holes are in their proper locations.

Mounted on the cylinder block - and standard M3 nuts and washers are too large...  So I guess that besides making studs, I'll be making nuts and washers as needed as well:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5055.JPG)

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: steamer on April 07, 2013, 05:48:29 PM
All that needs is some elbow grease...it's fine Arnold!...Keep going!

 :cheers:

Dave
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on April 07, 2013, 05:53:02 PM
Thanks Arnold for showing how to make a square hole (is this correct English?).

Just a thought.  If you decide to remake the valve disk how about making the middle portion around the square hole a little wider so that a 3mm nut and washer won't look too big.

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: Maryak on April 08, 2013, 12:59:17 AM
Arnold,

Nice work, I thought there was more than enough room for the nut and washer. Is it me or is that area narrower than the original 0.5", 12mm?

Best Regards
Bob
Title: Re: Arnold's take on the MEM Corliss
Post by: b.lindsey on April 08, 2013, 01:30:29 AM
Arnold, i don't see any laziness in your post at all...just some good efficient planning which we can all learn from....nice work as always.

Bill
Title: Re: Arnold's take on the MEM Corliss
Post by: larry1 on April 08, 2013, 03:52:34 PM
Arnold,  Great work and thank you for posting the pictures.     larry
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on April 08, 2013, 07:47:31 PM
Dave, Vince, Bob, Bill & Larry - thanks for checking in Gents  :praise2:

Vince, I think it's perfectly good to say it's a square hole  :ThumbsUp: .  There are other ways to make square holes - and a bit neater than I did, but for those one needs additional tooling - things like broaches or EDM machines and so on.  I don't have broaches, and they're a bit expensive, no EDM, and while I could have made up a broach from silver steel, it would have taken me much longer to do, so this just seemed the easiest solution here.  Another option was to run through the hole to square it up with a 1mm end mill - the ones I have can reach 5mm deep - and then just round over the corners on the pivot pin a bit to fit.  That might be a neater solution, but milling with such a small end mill can take ages...  So I opted for the much quicker file&go option.

It's possible to "cheat" a bit with the valve disk and spindle for anybody not interested in messing around with square holes and such...  The main reason for the square is to allow one to tighten the nut on the spindle with the spindle and hub already mounted on the cylinder block.  Instead of making the squares, just turn the square section on the spindle down to 3mm, make a slot at the big end for a flat screwdriver and leave the hole in the disk round at 3mm.  Then it's easy to assemble the hub, spindle and disk together before mounting the hub on the cylinder block.  The downside to this deviation from plans is that the disk arms mount to the back of the disk, so these would be fiddly to install later - or if installed to the disk before mounting the assembly on the cylinder block be prone to get in the way while mounting the assembly.  As so often happens building engines, it's a bit of swings and roundabouts - and one must choose where one would like to do the fiddly bits  :)

 :facepalm: Bob you're right...  I made that middle section only 6mm wide instead of 12mm  :Doh: - entirely my fault.

But I'll still have to make up smaller nuts... - the flange on the pivot mount is only 6mm wide, and standard M3 nuts don't have enough clearance to turn there.   

For starters I'll just use screws or cap screws where things are tight - the main thing is I want to get the engine to a point where it is fully assembled so we can set about exploring how to set the timing and maybe add that bit of detail to the plans thread.  I think I know how to set the timing, but I also think there's a bit of a gotcha involved...  Once its running, I'll get down to the detailing.

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on April 13, 2013, 07:53:20 PM
I had a shop session this afternoon.  As mentioned earlier, there are some areas where standard 3mm nuts will not fit for mounting things.  I need to get bits and pieces of the engine stuck together slowly for test-fitting parts together as they are made from now on, so I turned up a handful of 3mm bolts from some 5mm hex brass:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5062.JPG)

A note to fellow builders here:  The cylinder feet are particularly difficult to bolt on.  One's fingers can't get between the base of the mountings and the upper flanges - so a pair of pliers or tweezers is needed to get fasteners started in there.  In addition, there is very little room for using a spanner (wrench) to tighten up the inside fasteners of the mounting feet.  In fact, once the first mounting foot was bolted to the cylinder, I fiddled around for half an hour and couldn't get the second foot's inside fasteners installed at all.  If you're not in the mood for an inordinate amount of fiddling, it may be easier to keep the cylinder mounting base plates and T-top sections as separate pieces and add mounting holes for two or three M4 countersink screws between them.  That way, the "T" sections can be bolted to the cylinder block easily, and then the base plates screwed to those.

After the fiddling around, I felt in the mood for making something easier - so I turned up the piston.  It's a bit too-close a fit in the cylinder, but that's OK, as I still have to lap the cylinder bore out to smooth it up:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5063.JPG)
As you can see, I chose the "alternate" piston configuration.

On to the piston rod, and I chose a bit of 6mm stainless steel rod to make it from.  Here the piston end is turned down to 4mm and threaded with a tail-stock die holder:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5065.JPG)

The cross-head end received the same treatment, and the piston rod was done:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5066.JPG)

Digging around my materials, I found that I don't have suitable bronze for the cross-head.  Brass would do just as well, so I used some 22mm brass rod to make a start on that.  I turned it to a smooth slide fit in the cross-head guide, and then drilled and tapped it M4 to match the piston rod.  You might have noticed that I didn't add a tread run-out groove to the piston rod, so to make sure it screwed in nice and flat on the cross-head, I just used a center drill to add a generous chamfer to the threaded hole in the cross-head - now the piston rod can screw into it nice and flat:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5067.JPG)

I mounted the dividing head in the mill vise, and started milling the flat sides of the cross-head:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5068.JPG)

After the second flat was milled, I drilled a 5.9mm hole trough at the correct position:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5069.JPG)
That hole was then reamed to 6mm.

Seeing as I was already working on the mill, I just transferred the chuck to the rotary table and used a slitting saw to part the cross-head from the parent stock.  Here is where I stopped - with just a tiny sliver of metal still left to cut.  Any further, and one have to play "Find and pick-up" after the part got flung somewhere during final separation:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5070.JPG)
Also clearly visible in this photo is the "generous chamfer" I mentioned earlier.

After de-burring the cross-head, this is the set of parts for today:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5072.JPG)

I stuck that lot in the engine and ended for the day:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5073.JPG)

There's still a bit of tightness when moving the piston rod, so I'll have to find out where that's coming from.  It shouldn't be difficult to fix though, and I have a hunch once the cylinder is lapped it will be gone.

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on April 13, 2013, 09:32:51 PM
Slowly but surely, bit by bit, it is getting together and it is looking really good. :ThumbsUp: :ThumbsUp:

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: steamer on April 13, 2013, 10:49:10 PM
Looking good from here!

Dave
Title: Re: Arnold's take on the MEM Corliss
Post by: Captain Jerry on April 13, 2013, 11:28:20 PM
That is looking very good, Arnold.  The assembly shot gives a hint of things to come. 

I usually read your posts very carefully and several times as well but somehow I missed your explanation of the reason for the square shoulder on the valve disk shaft and the alternate method to tighten the holding nut.  It might have been more appropriate to post my solution at the time but others may like this alternative that I used on my earlier Corliss.  The problem is that the shaft rotates freely in the mounting plate making it impossible to torque the nut on the end.  My solution was to drill an oil hole in the top side of the mounting plate spigot and a corresponding hole through the pivot shaft. To torque the nut on the end, just stick a pin in the hole to lock the shaft and torque the nut.  With the pin removed, the hole provides a convenient way to oil the shaft.  I found that there were other times when it was helpful to be able to lock the shaft such as during assemble of the linkage and adjustment of the valves.

I do thoroughly enjoy your detailed progress posts.

Jerry

Title: Re: Arnold's take on the MEM Corliss
Post by: Tennessee Whiskey on April 13, 2013, 11:57:43 PM
Arnold, great job with the files. There have been many a fine double barrel hunt your land that were built using a great bit of hand filing. :cheers:

Yo Redneck
Eric,
Title: Re: Arnold's take on the MEM Corliss
Post by: swilliams on April 14, 2013, 12:01:23 AM
Nice Arnold

Looking impressive

Steve
Title: Re: Arnold's take on the MEM Corliss
Post by: Bearcar1 on April 14, 2013, 12:12:55 AM
IIRC, Arnold, you had mentioned the height of the mounting feet as being a bit on the shallow side and had thought about making them taller. This of course would have made an impact on the heights of the bearing standards and so on. Anyway. I am certain you will no doubt ferret out any other *surprises* that may lurk in this design. This type of thing is mainly just a minor inconvenience and nothing more. You are soldiering on like a trooper. :ThumbsUp:


BC1
Jim
Title: Re: Arnold's take on the MEM Corliss
Post by: Don1966 on April 14, 2013, 01:12:11 AM
She's really starting to look good Arnold and as Steve said very impressive. Still following here with great interest.

Don
Title: Re: Arnold's take on the MEM Corliss
Post by: sbwhart on April 14, 2013, 06:34:03 AM
She's comming on well Arnold  :ThumbsUp: :ThumbsUp: :ThumbsUp:

Stew
Title: Re: Arnold's take on the MEM Corliss
Post by: Stilldrillin on April 14, 2013, 08:36:38 AM
It's nice to see the parts coming together Arnold!  :)

David D
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on April 14, 2013, 06:31:38 PM
Many thanks to everyone who checked in  :praise2:

Jerry, using the oiler hole and drilled hole is a nifty solution - thanks for mentioning that  :ThumbsUp: - its always good to have many options for doing things.

No progress on the engine for me today - I spent it  :happyreader: and  :killcomputer: .  I had a bit of a hectic week at work last week, and some late evenings in the office impeded on study time, so I had to catch up a bit.

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: zeeprogrammer on April 14, 2013, 09:18:32 PM
Just wanted to say I've been watching and admiring.
Title: Re: Arnold's take on the MEM Corliss
Post by: b.lindsey on April 15, 2013, 12:53:48 AM
Always happy to see your updates Arnold...she's looking REALLY good!!!

Bill
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on April 21, 2013, 10:36:32 PM
Thanks Carl and Bill  :praise2:

 :facepalm2: I need to convince my bosses I need a holiday... 

Had a five hour shop session today.  The connecting rod looked like a good candidate to start work on, so I dug around for stock to make it from.  A while ago I was given a piece of 20mm mystery steel bar.  It was lying amongst some printer shafting, and while the printer shafting had started to rust slightly, this bar didn't have a single spot of rust on it.  And compared to some shined-up silver steel, it has that little "extra whitish shine" that indicates high chromium content...  So, it's stainless, but I don't know exactly what grade.  It was cut both ends with an abrasive cut-off saw, and the discolouring on the ends would be something to stay away from, so I used the band saw to saw off a 4mm slice from one end to get rid of that. 

I've worked a bit with free-cutting stainless, so when I tested the sawn off end with a file, I could immediately feel that this stuff was tougher than free-cutting stainless...  This was going to be a challenge to machine.  I took a couple of minutes to think trough all I've learned about machining stainless.  Lower speed.  Use very sharp tools.  Lubricant/cutting fluid helps.  Use a steady feed rate and never let the cutting tool rub.  Heat is the enemy.  Look and listen to what the machine is doing.  And last - not a machining rule, but one that seems to have helped me a lot - be positive; that's half the war won.

So, I decided to take on the "difficult" steel, and thought through all the machining operations.  Then I sawed a suitable length off the parent stock:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5076.JPG)
That was center drilled in the lathe at one end for later turning operations.

Off to the mill, and with a sharp 16mm HSS 4 flute cutter at just 80rpm spindle speed, I started by milling off a 2mm deep flat on the round bar.  At the start of the cut I just plunged in, feeding the X axis at about half the speed I would normally for mild steel, and checking that chips were coming off.  Once the cutter was about half-way onto the workpiece it sounded like and felt like I should increase the feed rate a bit, which I did, and all of a sudden some nice equal-sized chips started coming off,  the mill's gearbox quietened down, and the sound of the cutter shaving off bits of metal went from a raggedy gdgdgdgdgd to a nice even swish-swish-swish sound.  The surface finish was far from perfect, but the cutter didn't break, the workpiece didn't work-harden, and I was a very happy chappy  :cartwheel: :
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5077.JPG)

I milled some more off the one end - this will become the crank end:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5078.JPG)

The holes for the crank pin and cross head pin were also drilled and reamed to 6mm.  LOTS of cutting fluid while drilling and reaming...:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5079.JPG)

While milling the other (still round) sides down to size, the "feel" for machining this stuff started improving, and the surface finish got a bit better:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5082.JPG)

I milled out the slot for the cross-head guide next with an 8mm cutter and a slightly higher speed.  The slot should be square in the inside end, but at this point there was no way I could mount the workpiece to do that on the mill, so the inside end  is still round.  I'll file it square, or - perhaps - there might be a way to mill it square later on... :
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5083.JPG)

On to the lathe, and some clocking up needed in the 4-jaw chuck.  When I started in model engineering, I disliked setting up jobs in the 4-jaw.  But it's one of the most versatile and accurate ways of doing work on the lathe, so I've been playing a mental game with myself which has turned into it's own bit of workshop fun:  How close can I get it by eye, and then how quickly can I get the job centered to within the needed accuracy.  The rings on the chuck face and the jaw positions all help.  I got within 0.5mm all round on this bit according to the dial indicator.  The last couple of adjustments were easy - find the "low" measurement on each opposing flat edge, total them up and divide by two.  Ease off on the chuck jaw with the highest reading, and tighten up the opposite jaw.  Difficult to explain in words...  There's some good video explanations available though.  Here I was busy with that process:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5084.JPG)

A bit of turning started to make the workpiece think it should be round again - just 200rpm on the lathe and steady - but positive - feeds with a sharply honed HSS toolbit:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5086.JPG)

Then I turned off more stock - starting from approximately half-way along the workpiece toward the tailstock with a sharp right-hand turning tool:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5087.JPG)

I free-hand turned the beginnings of the fish-tail fish belly rod finish on it:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5088.JPG)

Then I did the same on the chuck side - turned everything down and added the fish-tail Fish belly section:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5089.JPG)

Some work with files and emery followed.  This stock was not the easiest to file - I had to go stroke-stroke-clean each time - with a personal bad habit of running the file in reverse against the palm of my left hand for each clean operation.  That can put some "metallic thorns" in the flesh...  A couple of grades of emery cleaned up the file marks:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5090.JPG)

There's still a bit of work left on the workpiece, but my shop time ran out  :( - So this is where I left off:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5092.JPG)

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on April 22, 2013, 06:19:50 AM
Nice one Arnold.  When you say fishtail, is that the same as taper turning?

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: smfr on April 22, 2013, 06:53:43 AM
I've seen it referred to as a "fish-belly"; two tapers blended in the middle.

Simon
Title: Re: Arnold's take on the MEM Corliss
Post by: EmanMyford on April 22, 2013, 06:55:03 AM
Well done Arnold,

I am still following your build with great interest!  :ThumbsUp:

Kind Regards.
Ewald
Title: Re: Arnold's take on the MEM Corliss
Post by: Jo on April 22, 2013, 07:11:48 AM
Nice one Arnold  :ThumbsUp:

How did you find turning the rod round for the second set of tapers? I normally aim to do fish bellies between centres as that way I can easily turn the rod around to turn the same tapers on both ends and the rod ends up symmetrical ;)

Jo
Title: Re: Arnold's take on the MEM Corliss
Post by: NickG on April 22, 2013, 07:50:44 AM
If you use the compound slide on the same setting and get down to the right root dia on each end they should meet in the middle?
Title: Re: Arnold's take on the MEM Corliss
Post by: Jo on April 22, 2013, 07:54:50 AM
You are a better man than I am if you can get your compound slide to take the same angles multiple time without a lot of faffing around.

Jo
Title: Re: Arnold's take on the MEM Corliss
Post by: NickG on April 22, 2013, 08:07:20 AM
Don't see why it would change if you hadn't moved it  :shrug: as long as it's supported and you get to the same route diameter (easy from cross slide) the length of the taper should be the same. People use the same method do do valves and cages + morse tapers etc.
Title: Re: Arnold's take on the MEM Corliss
Post by: Jo on April 22, 2013, 08:13:00 AM
True fish bellies use multiple tapers = you need to set the compound slide to a number of different angles.

The issue is not the cutting of the tapers but turning the work around with the compound slide at each setting and squaring up the work each time in the four jaw. Doing it between centres means there is no truing up to do  ;).

Jo
Title: Re: Arnold's take on the MEM Corliss
Post by: NickG on April 22, 2013, 12:00:56 PM
Ah I see, thought it was just 1 taper, sorry.
Title: Re: Arnold's take on the MEM Corliss
Post by: b.lindsey on April 22, 2013, 12:09:56 PM
That came out beautiful Arnold!!!  And as always, nicely done on the pictures and set-ups too. I think its about time for another family picture of all the bits so far too :)

Bill
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on April 22, 2013, 10:39:30 PM
Thanks all who checked in  :praise2:

Vince, Simon is correct it should be fish belly - don't know where my thoughts were when I called it fish-tail  :-[

Bill, it's not finished, so there was no family shot.  Hopefully I get some time this coming weekend to finish it, another part, and start to mount things... That's a family picture I'm really looking forward to  :)

 :Director: Now, listen to Jo everyone - her description is a much better method of turning fish bellies.  IIRC, Jason also did a very good write-up on turning them, as did Stew a couple of days ago.

Like Jo mentioned, fish bellies are actually made up of more than one angle which then gets blended together to form a curve.
If you look closely at my fish belly you'll notice it's slightly asymmetrical - that's because I was lazy and didn't even bother with setting angles on the top slide to cut by.  It was just eyeballed with some coordinated in-feed on the cross slide while feeding along the length - you can see the "steps" in the third-to-last photo - before having at it with the file - also just to eyeball mk1.  This won't pass muster in a model engineering engineering competition, and on an engine with more than one similar fish bellied rods it would stand out like a sore thumb.

For those that don't want to mess with setting the top slide and want a good result, there are some other ways of getting fish belly - and  for that matter, other turned curves - done. 
Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on April 22, 2013, 10:44:04 PM
Thanks for the info Arnold.  Hopefully I will remember it when I come to do it.

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on May 04, 2013, 06:41:24 PM
Pleasure Vince  :)

Things have been very topsy-turvy in my world the last two weeks, and shop time suffered badly.  It's not all doom and gloom though; my sister visited from South Africa for a couple of days, and besides pleasant company she brought along a box of riches.

A set of 0 to 10 BA taps and dies that belonged to my grandfather, who sadly now has reached the age where he cannot continue doing much in his own shop.  My dad could have grabbed the set, but he passed it on to me - so thanks Grandpa and Dad  :NotWorthy: .
By all accounts the set is more than sixty years old - and still complete; a great tribute to how well my grandpa looked after his tools.  It looks to be carbon steel, but very well made and high-quality, and all stamped LAL - Made in England.  At some point Grandpa added a couple of extra holes for some metric die nuts as well:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5095.JPG)

On to a bit of shop time for a change.  The connecting rod still needed quite a bit of work to finish off.  First was to square out the rounded section left on the inside of the fork end (if you have a look at the last photo I posted before this, you'll see it).  I left this on purpose earlier on; I had no easy way to mount the workpiece vertically to mill out the excess, and would have had to resort to filing for that.  But with the crank end now much smaller than when I started, it was easy to just stick the four-jaw chuck on the rotary table and chuck it up to mill out.  When I made the RT I left it's spindle hollow to cater for scenarios such as this:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5096.JPG)

All done:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5097.JPG)

Off to the big vise for a spot of filing to get rid of tool marks - I thought it would be a heck of a job to do this, as this stainless is a bit on the tough side, but it filed very nicely:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5098.JPG)

A quick check on what's built of the engine so far, and it was obvious that the tapered sections from the plans are definitely needed on the forked end of the connecting rod, so I meticulously set up the workpiece to eyeball Mk1 in the milling vise - a thin drill through the hole in the fork end to allow as much clamping on it as possible, and a bit of plate to support the other end at the approximate angle needed. Depth of cut was set to _just_ start removing metal at the center line of the hole through the fork:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5099.JPG)
Please don't adjust your spectacles; I don't know where the focus was on that photo  :-[

A bit more filing and rounding over, and the connecting rod was done:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5100.JPG)

A quick turning session on the lathe, and some 8mm hex brass ended up in the crosshead pin and screw.  Being my normal lazy self, I left the parting pips on for the next operation:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5101.JPG)

I must get my grubby hands on some ER25 collet blocks...  I abused my home-brew lathe collet chuck by lightly clamping it up in the mill vise.  Then I eyeballed a 1mm slitting saw against the parting pip to set center height to cut the screw slot:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5102.JPG)

Done:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5103.JPG)
While typing this up tonight, I suddenly remembered something, and I owe Stew (sbwhart) an apology: - Sorry mate; I forgot I promised some photos of using the height gauge to set up jobs like this.  I'll try and do a mock-up for you in my next shop session.

I changed the 6mm collet for a 3mm one, and cut the slot on the "screw" section of the pin as well.  I've found that grabbing on to threaded sections with collets does not damage the threads for light machining operations.
The bits screwed together:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5104.JPG)

A family photo - here one can clearly see why the tapered sections on the fork end is needed.  If those were not done, the fork would get interference in the cross-head guide bore:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5107.JPG)

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: fcheslop on May 04, 2013, 06:46:44 PM
Hi Arnold, that the same set of taps and dies I have didn't realise they were that old :ThumbsUp:
Iv just been quietly following along you're nice build its on my list :Lol: as are a lot of things
cheers
Title: Re: Arnold's take on the MEM Corliss
Post by: Jo on May 04, 2013, 06:58:52 PM
I like your crosshead pin design Arnold  :ThumbsUp:

In fact the whole connecting rod is looking good  8)

Jo
Title: Re: Arnold's take on the MEM Corliss
Post by: tel on May 04, 2013, 08:51:35 PM
Quote
In fact the whole connecting rod is looking good  8)

Agreed! The whole job, in fact - you are making very good progress.  :ThumbsUp: Only wish I could find the time to get back to my build!
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on May 04, 2013, 10:26:45 PM
Arnold

Love your (and also Jerry's) family photos of the parts coming together.  For someome like me with an inexperienced eye, it puts things from the drawing in perspective.

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: Maryak on May 05, 2013, 02:05:45 AM
Arnold,

As always fantastic job on the Corliss.  :praise2:

Heirloom tools are very precious and I'm envious because mine were stolen when thieves broke into the Maritime Museums workshops some 7 years ago. Sure I bought replacements but it's just not the same. So please keep them in a safe place.

Best Regards
Bob
Title: Re: Arnold's take on the MEM Corliss
Post by: Don1966 on May 05, 2013, 02:42:45 AM
I like your crosshead pin design Arnold  :ThumbsUp:

In fact the whole connecting rod is looking good  8)

Jo
I agree great job and lessons are being learned following along. Thanks Arnold.

Don
Title: Re: Arnold's take on the MEM Corliss
Post by: Pete49 on May 05, 2013, 05:03:29 AM
Great job Arnold and keeps me interested  ;D
Pete
Title: Re: Arnold's take on the MEM Corliss
Post by: steamer on May 05, 2013, 10:22:59 AM
Looks great from this side of the pond Arnold!....Glad your not sleeping at your keyboard and are instead in the shop! :ThumbsUp:

I have a set of dies from my Dad....I think of him everytime I use them

Goodonya mate!

Dave
Title: Re: Arnold's take on the MEM Corliss
Post by: b.lindsey on May 05, 2013, 11:15:58 AM
Lovely work all around Arnold. The connecting rod alone is a work of art!!

Bill
Title: Re: Arnold's take on the MEM Corliss
Post by: zeeprogrammer on May 05, 2013, 12:46:39 PM
Beautiful connecting rod Arnold.
I wish I were as 'lazy' as you.  ;D
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on May 11, 2013, 10:40:31 AM
Thanks to all who responded  :praise2: :praise2:

With regards to the very positive feedback on the connecting rod: Thank you all.  This part is one of those rare occasions where I stepped back and was pretty much satisfied with how it came out.  And it was a huge learning experience for me; I'd never machined stainless steel to this extent.  Actually I'm quite surprised at how well it went, and some of the lessons learned might just help improve my finishes on mild steel as well.

Vince, I'm as inexperienced as you are.  In fact, we're all learning from each other, and that is what MEM is about.  Have a look at my post today, and give yourself a huge pat on the back; I think you did a much better job on the crankshaft than I did  :NotWorthy:

Carl, it can take a bit of effort to be lazy  :lolb:

I have a four-day long weekend - we had a public holiday yesterday and I took leave for today.  Yesterday was spent doing all kinds of needed odd-jobs around the house; banal things like changing water tap (faucet for the US people) washers on leaking taps, giving the kitchen oven a really good scrub-down and so on.  A big part of today was spent running around town to do one of the things I hate most - shopping; and mostly trying to find sensible, presentable, subdued and comfortable attire; I'm not a natty dresser and it's really hard to find the type of boring clothing I like  :Lol: .  The highlight of my shopping was a visit to the metal store, though they didn't have everything I wanted.

I managed a couple of hours in the shop this afternoon though.  I'm trying to steer away from mild steel for parts of the engine that will not be painted.  The crank web is one of those, and I could not get suitable stainless, so I decided to make it from bronze.  A bit from the offcut bin volunteered, and after locating the edges I brushed some permanent marker ink on it and spot-drilled in the needed locations - very lightly at the crankshaft end:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5109.JPG)

The lightly spotted hole was used as a pivot to mark out the periphery of the web for later operations:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5110.JPG)

I love my camera to bits - it works very well, but it does have one vice...  The batteries last for hundreds of photos on end, but between the time it shows a low battery warning and completely shuts down, it can take just two or three photos...  Today was such a day.  Off to the charger with the batteries, and some minor work happened.

The crankshaft end of the web was drilled and reamed 8mm - the "slightly scaled down" 24mm to the inch I'm working on called for 9mm for the shaft, but that's a hard-to-find size of shafting locally, so I had a choice of 8mm or 10mm, and back when I built the bearing blocks I'd already decided on 8mm (~= 5/16" for the non-metric people).  I'll also be fixing the web to the shaft with bearing retainer, and pin it, so I just plonked the reamer right through, rather than making a press-fit like Vince did.

I also drilled the crank pin hole 3.3mm and tapped it M4. With the camera batteries charged up a bit, I took this photo after using a scribing pin in the mill chuck to mark out some more on the workpiece - the DRO is nice for that as well:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5111.JPG)

On to a bit of shaping...  Once again I cheated / was lazy.  Setting up the workpiece to mill off some excess, I just used a long 4mm cap screw and a drill bit to set things up.  The cap screw was long enough that it's "cap" section didn't touch the vise. Most metric screws are smaller than nominal size if measured over the threads.  This M4 cap screw measured 3.8mm across threads.  To keep things sort of parallel I used a 5.9mm drill  as a spacer in the "big" hole and milled out   the rest:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5112.JPG)

A bit of facet milling worked OK to shape the roundy-bits:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5113.JPG)

Some filing followed and I ended up with the web and  shaft:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5114.JPG)

Family photo - I didn't have time to make the crankpin.  The shaft and web are loctited together to set up so I can drill and pin it:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5115.JPG)

Kind regards, Arnold
 ::) Posted the morning after, as my Internet was down last night.
Title: Re: Arnold's take on the MEM Corliss
Post by: Jo on May 11, 2013, 10:49:06 AM
A big part of today was spent running around town to do one of the things I hate most - shopping; and mostly trying to find sensible, presentable, subdued and comfortable attire; I'm not a natty dresser and it's really hard to find the type of boring clothing I like  :Lol:

A man after my own heart  :ThumbsUp: I can never understand why women are supposed to like shopping :facepalm:  and as for buying clothes  :hellno:

She is coming together nicely   :)

Jo
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on May 11, 2013, 12:29:25 PM
Good progress Arnold.

Quote
A bit of facet milling worked OK to shape the roundy-bits

I need to give that method a try.  Maybe on the top of the bearing blocks I am making at this time.

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: b.lindsey on May 11, 2013, 01:19:01 PM
Lovely work as always Arnold . Enjoy your long weekend :)

Bill
Title: Re: Arnold's take on the MEM Corliss
Post by: Don1966 on May 12, 2013, 01:27:10 AM
Nice touch on the crank web Arnold, she's starting to shape up and looking good.

Don
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on May 12, 2013, 05:06:35 AM
Thanks Jo -  Not to mention shoe-shopping  :Lol:   Got a Swedish clog thrown at me once for presenting a pair to an ex girlfriend after she tried on nearly all the shoes in the shop.  I think my last statement before the wooden footwear headed my way was "Heck, they should be comfy and kick up just as much of a racket as the last twenty pairs of high heels you tried on"  :LittleDevil:

Vince, thanks.  I saw from your last post you decided against the facet milling - that's just fine.  One of the freedoms of our hobby is that each and every one of us can do as we please in our shops.  There's no right or wrong.  Any way a part can be made safely is right  :)

Thanks Bill  :) - I am enjoying it !

Not much done today - but I did manage to add the mini how-do-I that I promised to Stew earlier on.

With due apologies to Bob Maryak, I deviated a bit from the plans for the crank pin.  Rather than using steel for it, I decided to make it from a combination of steel and brass.  The selection of materials is more "technically" correct rather than "hobby" correct; for hobby use all-steel would do just as well.  And, anyway, I used what I have on hand.  I could have made the entire crank pin from brass, but the M4 threaded section would carry quite a load while the engine is running.  The flywheel will end up carrying quite a bit of momentum, and IMHO in the overall design, the crank pin will be the weakest spot.

So I turned up the crank pin to dimensions, but rather than threading the end, I drilled, threaded and Loctited an M4 cap screw in there:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5116.JPG)

The cap screw was sawed off to length with a junior hacksaw, and the end cleaned up with a file.

I promised Stew some photos of how I use my home-brew height gauge.  There's a mini how-to (my way) coming up, but first off, for those that have not seen it yet, a year or two ago I built a height gauge that uses off the shelf unmodified cheap digital calipers - it can take both 150mm (6") and 200mm (8") calipers.  I've only ever used it with the 150mm caliper, and, contrary to my original intentions of leaving the caliper stock standard, I've sawed off the "sticky outy depth gauge part" - that is the long thin section that is attached to the moveable head.  For reference, this is what the tool looked like the day it was finished:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_1869.JPG)
Unfortunately, some of the shiny bits picked up a lot of rust afterward  :embarassed:

First off, I measured the diameter of the workpiece with a caliper -it measured out to 9.88mm
Then I chucked it up in the collet chuck, and mounted the lot in the mill vise.  The mill bed was cleaned thoroughly  ( any swarf on there will throw out the readings in the next steps).  The height gauge was set to the top of the workpiece.  The read-out part of the height gauge is not visible here, but it's the only way to get the measurement.  So it was just moved down to the workpiece with the foot on the gauge touching the workpiece, and the caliper's lock screw tightened:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5117.JPG)

With the gauge reversed so I could see the display, It was zeroed.  Analogue gauges won't have this option. :
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5118.JPG)

Having measured the workpiece diameter (9.88mm) earlier, it is easy to set the caliper to half of that (-4.94mm) to find the center line:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5119.JPG)

For reference, this is how the gauge compares to the workpiece after the last step:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5121.JPG)

With the digital gauges, it's easy to zero it off on the workpiece  center :
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5122.JPG)

For the slot in the workpiece, I wanted a 1mm slot.  To set the slitting saw on center for that, I needed to halve the width of the saw. 1/2 = 0.5. So I adjusted that offset on the caliper:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5123.JPG)

I used that to set the height of the slitting saw by manually turning the mill spindle till the slitting saw blade _just_ touched the height gauge foot.
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5124.JPG)

All slit and done - and the end of the mini how-to:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5125.JPG)

The final part:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5126.JPG)

The crankshaft and web needed pinning.   I poked a 2mm hole inn the lot - keeping the spindle speed on the low side so I wouldn't work-harden  the stainless steel shaft while drilling:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5127.JPG)

Don't adjust your monitor folks;  a bad photo showing the 2mm bronze pin I knocked into the hole - with some retainer fluid included:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5128.JPG)

I snipped off most of the excess of the pin, and used a small hammer to peen it over:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5129.JPG)

Off to some filing, and the pin is just about starting to disappear:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5130.JPG)

All together after some emery work after the filing, and the pin is pretty much invisible. Have a mouse clicky on the photo and see if you can find it  ;) :
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5131.JPG) (http://www.nam-engineering.com/cm/displayimage.php?pid=7973&fullsize=1)

A part that's not in the plans: I turned up a thin washer to go between the cross-head and the web:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5132.JPG) (http://www.nam-engineering.com/cm/displayimage.php?pid=7973&fullsize=1)

A trial fit,,,,,and there was some interference.  The  crank rod was still a bit thick on the fork end, and left a score in the cross head bore:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5133.JPG)

Some filing on the crank rod solved that:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5134.JPG)

Finally some family photos:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5136.JPG)

(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5137.JPG)

With the edges knocked off the crank rod, everything works well.  A spacer might be needed between the crank web and the bearing though.

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: Maryak on May 12, 2013, 08:18:19 AM

With due apologies to Bob Maryak, I deviated a bit from the plans for the crank pin.  Rather than using steel for it, I decided to make it from a combination of steel and brass.  The selection of materials is more "technically" correct rather than "hobby" correct; for hobby use all-steel would do just as well.  And, anyway, I used what I have on hand.  I could have made the entire crank pin from brass, but the M4 threaded section would carry quite a load while the engine is running.  The flywheel will end up carrying quite a bit of momentum, and IMHO in the overall design, the crank pin will be the weakest spot.

A spacer might be needed between the crank web and the bearing though.

Kind regards, Arnold

Arnold,

Please don't apologise. All these mods are fantastic and individual ways of doing things are .............well................individual  ;D

I'm not so sure about a spacer, may pay you to wait until the flywheel, eccentric and governor drive pulley are fitted. Which should remind you, (and our other reviewers), about the peer review of the rest of the bits.  :old:

Best Regards
Bob
Title: Re: Arnold's take on the MEM Corliss
Post by: tel on May 12, 2013, 08:38:16 AM
Quote
All together after some emery work after the filing, and the pin is pretty much invisible. Have a mouse clicky on the photo and see if you can find it  ;) :

It'll do me for invisible - nice work!

Meanwhile my own version languishes on the bench - now I've knocked off to build a die filer! (Ain't it grand being your own boss) ;D
Title: Re: Arnold's take on the MEM Corliss
Post by: steamer on May 12, 2013, 08:41:08 AM
I see your modeling the latest in Dropbar protection!

 :ThumbsUp:
Title: Re: Arnold's take on the MEM Corliss
Post by: Maryak on May 12, 2013, 08:57:15 AM
I see your modeling the latest in Dropbar protection!

 :ThumbsUp:

Na...............he's just fezzing up to his awful taste in headgear  :slap:

Best Regards
Bob
Title: Re: Arnold's take on the MEM Corliss
Post by: Steamer5 on May 12, 2013, 09:17:29 AM
Tel,
 I'll email my brother for you & see if he's got a spare camel! Might take him a while to walk it down from the far north though....... :stickpoke:   :lolb:

Arnold,
 I've been quietly soaking up your build & enjoying it. I was round my Dads a few days ago, & ratting around in a pile of back issues of M.E. by chance came across an article on the valve gear for these engines, sorry forgot to write it down, I'll go round this week & hut it out & post up the issue etc, may be of use

Cheers Kerrin
Title: Re: Arnold's take on the MEM Corliss
Post by: steamer on May 12, 2013, 09:17:54 AM
Quote
All together after some emery work after the filing, and the pin is pretty much invisible. Have a mouse clicky on the photo and see if you can find it  ;) :

It'll do me for invisible - nice work!

Meanwhile my own version languishes on the bench - now I've knocked off to build a die filer! (Ain't it grand being your own boss) ;D


Start a thread on that Tel....love to see it!

Dave
Title: Re: Arnold's take on the MEM Corliss
Post by: tel on May 12, 2013, 09:26:29 AM
Pretty much just a modified version of the AME one - modified in the sense that I am building it out of materials to hand, so some of the sizes will be different. I'll start a post when I have a little more to show.
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on May 13, 2013, 06:34:50 PM
 ::) No progress to report unfortunately...  I was planning a bit of woodworking yesterday to get things mounted on the base, but felt slightly under the weather.  That's gone over into a full-blown flu  :facepalm2:

Thanks Bob
Quote
I'm not so sure about a spacer, may pay you to wait until the flywheel, eccentric and governor drive pulley are fitted. Which should remind you, (and our other reviewers), about the peer review of the rest of the bits.  :old:
You're right; I'll hold off on any spacers etc - those are easy enough to make later as/if needed.  And I haven't forgotten about the peer review; will try and make some time to see if I can contribute N$0.02 or thereabouts. 

Cheers Tel - I've also been eyeing the die filers...  Sure would be handy for this project.  I can't take time out for tool-making unless it's essential at the moment though; I'll already have to take out some shop time in the next month or two to make room for a new arrival in the shop and add some lighting to a couple of dark spots.  And I'm running out of electric wall plugs as well  :facepalm2:.
Fancy a bag of Turkish Delights, or would a nice baklava be more to your taste - or maybe Raki   :LittleDevil:

Thanks Kerrin  :) - All information is useful!

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: tel on May 13, 2013, 08:12:43 PM
The baklava would be good! At least you made no mention of organ grinder's monkeys - which is wot someone who used to be one of my daughters did! ;D
Title: Re: Arnold's take on the MEM Corliss
Post by: mklotz on May 13, 2013, 09:32:52 PM
...which is wot someone who used to be one of my daughters did! ;D

Love it.  I'm gonna remember that one.  I have two of those daughter things too and they provide ample opportunity for lines like that.
Title: Re: Arnold's take on the MEM Corliss
Post by: tel on May 14, 2013, 04:17:47 AM
You're very welcome Marv. The usual royalties will, of course, apply! ;)
Title: Re: Arnold's take on the MEM Corliss
Post by: b.lindsey on May 14, 2013, 01:34:47 PM
Great update as usual Arnold....sorry to hear about the flu though.  Take care of yourself and feel better soon!!

Bill
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on May 25, 2013, 10:19:30 PM
Thanks Bill  :) - took me a while to get over the 'flu, so nothing happened in the shop for a long time...

After spending the last two weeks sneezing, I was not about to get started on woodwork for a return shop-session; more sneezing from the wood dust would just be the pits.
I figured I might as well start on the flywheel, so I had a bit of a think about how to proceed with making it...

I checked some spacings on the lathe, and thought I might get away with making the flywheel rim without too much fuss.  If I hacked off a suitable length from the parent stock shown in an earlier photo, I could actually mount it on the 4 jaw chuck and swing it in the lathe's head gap to turn - and end up with a flywheel that's just 2mm narrower than the plans show.

On to the "simple" shop session that became an entire saga, and a hidden "gotcha".  There's not really a lot to see in today's update, though the tribulations might be amusing to some  ;)

A quick check on the bandsaw, and there was no easy way to mount the stock on it to start hacking at it.  A 4"x6" bandsaw really isn't built to saw a slice off a 180mm (7") bit of round stock...
Next option - a slitting saw on the mill.  I know my 1mm slitting saw cuts cast iron like butter, so I mounted the stock on the rotary table and 4-jaw chuck.  No problem with headroom, even though the lot stands a bit tall:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5138.JPG)

I started the cut, and promptly ran into a problem...  I forgot to check that the cut wouldn't make the chuck unscrew from its mounting on the rotary table - which it promptly did :-[ .  A new lesson was learned as well; my slitting saw arbor has a safety feature in it that I never knew of.  If things suddenly gets too tight, the holding screw shears off  :lolb: .  It worked well to prevent damage to the slitting saw.  Here's what remained of the holding screw - I'd already managed to get the rest of the screw removed from the arbor, replaced it and re-mounted the saw:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5139.JPG)

In the process of unscrewing the chuck, the slitting saw dug a nice trail of tooth marks  :facepalm2: :
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5140.JPG)
Something about the tooth marks looked wrong, but I didn't listen to my gut feel...

To prevent the chuck unscrewing again, I attacked things from the inside:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5141.JPG)

Soon after the last photo, the slitting saw arbor sacrificed another holding screw...  The alarm bells were ringing, but Arnold wasn't listening  :-[ .  Replaced the holding screw, started again, and not long before the screw popped again.  The slitting saw still felt nice and sharp, but I was not about to push things any further; the saw blade itself cost me three times what the stock cost, and I wasn't going to push things any further and risk breaking the blade and have bits of high speed steel flying around.  And I didn't hear the penny drop.

So, what next ?...  I could just go for the hacksaw, but my energy levels are still a bit low after the flu.  Tel mentioned a grinder...  Hmmm...  Got two of those; a 5" and a 12".  The 12" takes quite a bit of effort to wield, and I was not feeling up to man-handling it yet.  So, on to the 5" and the thinnest cutting disk I have.  Securing the workpiece was a bit of a problem, but I eventually managed to clamp it in the big vise on the workbench.  Things went OK until the blade started getting deeper into the slot, and then the blade started biting - a case of me not being steady enough.  Rather than risk breaking it, I stopped and did some more thinking  :headscratch: .  The penny didn't drop...

Back to the bandsaw...  I removed all the add-ons I'd made for it, checked things out, and eventually figured out I could clamp the workpiece to the extended bit of the vise:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5142.JPG)

Then I started abusing the poor bandsaw:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5143.JPG)
Saw a bit until the "head end" blade guide stops against the workpiece, stop, rotate the workpiece a bit, clamp up again and repeat.  The blade barely penetrated into the inner hole - it just left some short stringy burrs on the inside to show that it did go through.  Stringy burrs, and still, the penny didn't drop  ::)

There were still some thin sections that were holding the bit I wanted to the parent stock.  Seeing as this is cast iron, it's brittle, and a good whack with a hammer should just break it apart.  Took more than a single whack though:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5144.JPG)
I had to basically tear apart one last section that held the bits together - where the band saw lines met, they were a bit out of alignment. Took a lot of wiggling around to break off that bit, AND STILL THE BLOODY PENNY DIDN'T DROP!  :facepalm2:

On to the lathe, and mounted on (or rather over the body of) the 4-jaw chuck in the head gap.  I left just enough space for the chuck key, and the lot fits nicely in the head gap:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5145.JPG)

I had to set the top slide parallel to the lathe ways and crank it in to maximum to get enough clearance to be able to turn the workpiece without the carriage hitting up against it.  This literally is pretty much my Myford's limits.  There's some room left in the head gap, but even so, the cross-slide was just barely hanging on by a few threads on it's feedscrew.
With slowest speed back-gear engaged, I started turning the workpiece.  It was only during this operation that THE PENNY FINALLY DROPPED:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5146.JPG)

I was looking forward to the smell, taste and black hands that come from the dust of turning cast iron.  And fully prepared to duck the stream of tiny chips it makes.  This material didn't do any of that; it came of in stringy swirls, didn't generate dust or give me any of those other (to me) feel-good cast iron experiences.  In fact, I'm now pretty much convinced this isn't cast iron, but rather steel, and the bad experiences with the slitting saw, the stringy burrs on the bandsaw and all the rest adds up.  That changes the ball-game a bit, and I have to re-think how I'm actually going to construct the flywheel.

I finished the shop session by rough-turning the outside of the workpiece to get rid of the crud:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5147.JPG)

So, now I have to sleep on what I'm going to do next.  With the original intent of the material being cast iron, I was going to bore out the rim section I did today by about 50% on the ID, then cut off another shorter section from the parent stock to turn down to a press fit inside the rim and drill it on the periphery to fit the flywheel spokes.  Right now, I'm not keen on the "extra" ring idea anymore; I might just bore out the rim to leave an internal "ring" in it, make a hub and spokes, make that fit inside the rim and solder the lot together.  Choices... Choices...

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: b.lindsey on May 25, 2013, 10:31:17 PM
Quite a saga arnold!  Frustrating when everything seems to be working against you, but you prevailed. Have to agree, that sure dont look like cast iron.

Bill
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on May 25, 2013, 10:37:34 PM
Glad to hear you are feeling better.

That flywheel is a project on it's own.

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: Bearcar1 on May 25, 2013, 11:32:37 PM
Geesh, what an undertaking unto itself. I didn't catch on to what was a problem until you got into cutting the piece on the band saw, Arnold.  Glad you are feeling better BTW. The stringy shavings was what set off the alarm bells for me. Though it is a fair amount to handle this size of material, couldn't you still continue on with your original thoughts of an inner rim with holes drilled in it to accommodate the spokes? Dunno. The flywheel has proven to be a real bear for the few folks that are making this engine. Me. I'm laying back in the weeds until I have seen what/how everyone else has done it, THEN, I'll make a decision as to if I want to proceed.  :Lol:  Take care of yourself my friend and do avoid saw dust for a while. Use a good respirator if you do though please. Exotic woods can be hazardous to the respiratory systems of some people.


cheers


BC1
Jim
Title: Re: Arnold's take on the MEM Corliss
Post by: tel on May 26, 2013, 05:05:34 AM
Quote
I had to set the top slide parallel to the lathe ways and crank it in to maximum to get enough clearance to be able to turn the workpiece without the carriage hitting up against it.  This literally is pretty much my Myford's limits.  There's some room left in the head gap, but even so, the cross-slide was just barely hanging on by a few threads on it's feedscrew.

Yer gotta think outside the box matey, a stout boring bar, taking a HSS bit, mounted at the rear (operator's side) of the topslide will restore things to a more rigid condition. That's how I did this rim, tho, sadly, no pic of the actual set-up.

Title: Re: Arnold's take on the MEM Corliss
Post by: sbwhart on May 26, 2013, 07:35:59 AM
Hi Arnold

Pleased you're feeling better, I thought you'd been a little quite.

As Tel said when faced with a problem like this you have to think outside the box. If you flip the tool over and hold it in the near side of the tool post and run in reverse you'll have a far more secure set up, the metal doesn't give a dam which way the lath is running or which was round the tool is. like this

(http://i431.photobucket.com/albums/qq32/sbwhart/Potty%20Simpson%20and%20Shipton%20Short%20Stroke%20Engine/131_1697_zps594b97cf.jpg) (http://s431.photobucket.com/user/sbwhart/media/Potty%20Simpson%20and%20Shipton%20Short%20Stroke%20Engine/131_1697_zps594b97cf.jpg.html)

I take it you'll have to turn down the OD some to make the inner rim, well if you turn it down whilst it's still on the parent material, this way you've thinned the section down so you could then part it off from the inside with a cranked tool or use the same tool upside down  working from the outside.

Hope this helps I'm sure you will come up with a solution.

Stew
Title: Re: Arnold's take on the MEM Corliss
Post by: tel on May 26, 2013, 09:02:12 AM
yep, there's how it's done, right there!
Title: Re: Arnold's take on the MEM Corliss
Post by: zeeprogrammer on May 26, 2013, 11:25:38 AM
Glad you're feeling better Arnold.
That was a fun post to read although I could feel the frustration build as you went along.
Title: Re: Arnold's take on the MEM Corliss
Post by: ozzie46 on May 26, 2013, 02:18:12 PM


   Glad you're feeling better Arnold. Your flywheel saga is going to give some valuable lessons for us mere mortals.  Will be watching and learning.

   Ron
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on May 26, 2013, 07:47:52 PM
Thanks all  :praise2:

Bill, yes, it's definitely steel.  The biggest problem was that I was trying to machine it like cast iron, and I was just plain miffed at myself for not catching on sooner that it was steel; all the signs were there  :-[
Vince, you know it   :cheers: - fortunately I won't have as much milling to do on this one as you did  ;)

Jim, thanks my friend.  Just make sure those weeds aren't wet, else you might also end up with the 'flu  >:D .  You'll be happy to know that I'll be hacking off another piece from the parent stock to make the inner rim, just like originally intended.  I don't think everyone will have as many problems with the flywheel.  There is the option of buying a casting for most.  The biggest problem for me is that it's a rather big job for my lathe.  I'll have to start saving up  ;D

Tel & Stew - yes, the boring bar was my next option.  Unfortunately, it's one of those "make-a-tool-first" options  :ROFL:
Stew, good tip about running the lathe in reverse.  I can't do that though; the Myford uses screw-on chucks, so machining in reverse could prove interesting...

Thanks Carl - had to try and make the post a bit of fun, otherwise it would be terribly boring  ;D . 

Thanks Ron - but I'm as much a mortal as everyone else.  This build (not just the flywheel, but the entire engine) is a steep learning curve for myself, as it's a much bigger engine than I've built to date, so there's a lot of new techniques that I have to use.  It's a lot of fun though!

There's not much to show for today's shop session, though I made lots of chips.  Now that I know this is steel, and that I'm going to make the flywheel with a separate inner rim, I finished off the rim to a better standard, and started boring out a lot of excess.  This was slow-going; to get any kind of sensible surface finish, I had to go right down to lowest back-gear speed.  That also meant fine feeding.  On the ML7, the apron feed is a bit coarse, so I just locked it to the leadscrew and fed with the leadscrew handwheel.  That gives a finer and more controllable feed.  I did something I've never done, and that was pull up a stool next to the lathe, and sit down while working   :-[ .  Eventually got to this state:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5149.JPG)

Once that was done, I reversed the jaws in the 4-jaw chuck, and clocked up the rim in it again to start work on the other side.  It clears the lathe bed by 1mm on the front part of the bed, and by just 0.7mm on the back part...  That should be enough; it's a bit close, but I'm not going to be heavy handed during the rest of the operations; slow & steady will get the job done just fine:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5151.JPG) (http://www.nam-engineering.com/cm/displayimage.php?pid=8030&fullsize=1)

After setting up, I faced off the front to true it up; no photos of that.  And then I had to call it a day; four hours gone and not much to show for it  ::) - this might be a bit slow  :lolb:

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: Tennessee Whiskey on May 26, 2013, 08:13:20 PM
Good problem solving. Now, keep your eyes on the indicators and quit worrying bout the clock. 8) I'm sure none of here are going anywhere, on our own accord at least. :cheers:

Yo Redneck,
Eric
Title: Re: Arnold's take on the MEM Corliss
Post by: Jo on May 26, 2013, 08:18:58 PM
Arnold you can always sneak up on it from behind:

(http://i214.photobucket.com/albums/cc12/jothoms/corliss/machiningtheflywheel-1.jpg)

Or in the case of a Myford make yourself an extension that bolts on using that spare tee slot in front of the standard tool post. Nothing sexy just a piece of thick steel bar with a holes to enable you to clamp in that tee slot, (or clamp it down at a jaunty angle if you are going  :o really wide) ... If you have the original Myford tool post kicking around all you have to do it put a 7/16" BSP stud in the other end and you can transfer over the ball handled clamp as well.

Jo
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on May 26, 2013, 09:01:47 PM
Way to go Arnold.  Slowly but surely.  That's my motto.  That flywheel surely goes beyond the limits of our lathes (at least mine).

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: Don1966 on May 26, 2013, 09:08:14 PM
As the others have said, yes nice save. One of the good things that I like about this hobby, is that it's makes you think and that programs us to overcome adversities. You have shown that here, great job Arnold and a good lesson for us beginners. Thanks!

Don
Title: Arnold's take on the MEM Corliss
Post by: ths on May 26, 2013, 09:57:11 PM
Nice going Arnold. I guess you're not at the extent of the lathe until you can't do it. I think you were nearly there though!  Cheers, Hugh.
Title: Re: Arnold's take on the MEM Corliss
Post by: Ginger Nut on June 02, 2013, 03:42:32 AM
Sticking my nose in so I know where to come back to to watch the masters.
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on June 02, 2013, 09:59:09 AM
Eric, Jo, Vince, Don, Hugh & Ginger Nut - thanks very much for checking in  :praise2:
Neat tips Jo  :ThumbsUp: - I have all the needed original bits for the Myford, including some rare additions (I absolutely love the clutch  :Love: )  For this project I think I'm sorted, but I'll keep your suggestions in mind  :)

Ginger Nut, no master here; just an amateur sharing trials and tribulations and very much also still learning along the way.

Some more slow & steady work yesterday.  There's still not much to show for it, but I'll do it anyway  :LittleDevil:

I've never had much success using carbide tipped tooling on the Myford, but to try and speed things up a bit, I decided to give the one insert boring bar I have a go.  Much to my surprise, it ended up giving a good finish, as long as I didn't try and take more than 5 thou feed at a time (that's 10 thou off the diameter) at highest back-gear speed.  With sharply honed HSS bits, I could go at 10 thou feed at medium back-gear speed, but the finish was worse.  So cuts ended up taking about the same time for both types of toolbits for the same amount of metal removal, but with the carbide giving me a better finish, I stuck to that.

I bored out the rim to meet up with the previously thinned out section at the headstock end.  It's always nice to see two separate bores that have to meet up at the same size do so very nicely after spending a minute or three really trying to clock up things as close as possible.  There is the tiniest bit of eccentricity, but I can't even feel that with my finger, and only the "line" in the cutting fluid gives it away:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5152.JPG)

The rim section is 32mm wide, and I want the insert section to be 10mm wide, so I bored out another section 21mm long 0.1mm over size to leave a ring for the insert section to seat against, using a long-travel dial indicator mounted on the bed to get the correct depth:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5153.JPG)

Once the flywheel is complete, this difference would not be noticeable to most people, and, in fact, I can still compensate for it at a later stage:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5154.JPG)

Back to the band saw, and a slightly revised clamping set-up:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5155.JPG)

I got myself a cup of coffee, and settled down to letting the saw do its bit; stopping each time the top blade guard bottomed out on the workpiece, turning the workpiece a couple of degrees (about 20o in this case for each step), re-clamp, and repeat.  The coffee was long-gone at the 75% mark when the familiar snap sound let me know the blade had broken.  I've drooled over the nice bi-metal blades available to people overseas, but locally I can just get the cheap carbon steel blades.  Fortunately, they are cheap, so I always keep at least two spare in stock.  So, I replaced the blade and let it carry on.  The new blade made things a bit faster, and soon I got to see how closely the cuts would meet up:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5156.JPG)
Far from perfection, but close enough, and I didn't have to hack away at it like when I cut off the rim section  :cartwheel: .  On doing what I thought to be the second-to-last cut, the workpiece unexpectedly separated from the parent stock.  Dropped right on my toes before I could get my foot out of the way.  Fortunately it didn't hurt at all - there's something to be said for steel capped safety boots besides that they are very comfy  ;D

The two pieces after separation; the cut still looks like a dog's breakfast, but certainly better than last time around:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5157.JPG)
 ::) Don't know where the saying "Looks like a dog's breakfast" comes from...  my mutts actually have higher expectations  :LittleDevil:

Anyhow, that bit was roughly chucked up on the lathe - by eye only, as there was absolutely no reliable references to take readings off, and then I faced it and turned the OD to get two reference surfaces:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5158.JPG)

The workpiece was then turned around and clocked up in the 4-jaw chuck again - using the faced end against the chuck jaw faces to seat it against, and the rim section within about 0.005mm eccentricity.  I wanted the rim fairly accurate, as it would be reversed in the chuck for a later operation and be clocked up closely again.  Then the inside was bored out till it was cleaned up - but not all the way to boring into the chuck jaws.  As the workpiece was still a bit long, the rest will get removed while facing off later:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5159.JPG)

I noticed some interesting things while clocking up the workpiece again...  I had some issues... I couldn't get consistent readings on the dial indicator.  After looking at what was happening, I eventually came to the conclusion that the workpiece was distorting while tightening up the chuck jaws.  I got closer readings at each jaw mount than in between them.  Maybe I was just too ham-fisted ?
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5160.JPG)
 ::) Should have taken a video of that lot....  I settled for an average reading between the low and high points.

The ring was faced off to length, and the ridge that was left during the last operation disappeared:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5161.JPG)

I stopped there for the day; I only have a rim to show for a lot of turning work:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5162.JPG)

And of course, Swarf Mountain  :Lol: :
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5164.JPG)

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on June 02, 2013, 10:55:15 AM
Coming along nicely Arnold.  I know the feeling;  a whole day machining and nothing to show for it.  Good thing my flywheel is finished. :naughty:

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on June 03, 2013, 02:15:39 AM
Thanks Vince. At least there's more to show for today  :)

With the inner rim coming along , I had a bit of a think about the steps to come.  It would be easiest if I could assemble the inside bits of the flywheel with the inner rim mounted up ready to turn of spoke excess without having to move the whole lot in between - sounds a bit funny, but the rest of the post will hopefully clarify that.

So first I re-mounted the rim on the ends of the jaws in the 4-jaw chuck, once again carefully clocking it to run as true as possible on the chuck.  Using this set-up, I can later on add the spokes and hubs without any of the jaws interfering and without taking the ring off the chuck.  Then I turned the OD down some more, but still left it about 1mm oversize for later machining:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5165.JPG)

I took the chuck off the lathe with the ring still mounted, very carefully so as not to bump anything and put it down out of the way.  I chucked up a bit of 30mm hot rolled steel in the 3-jaw and started turning it down to make the hub.  I've mentioned a lot in the past that this specific steel is horrible stuff to turn to an acceptable finish...  Well, I think I learned something while juggling the the big rim; sometimes less is more.  Lower speed, and a reduced depth of cut, and I got a finish from it that in the past took the application of a lot of filing and sanding.  Still not the same finish as I can get in other metals, but progress  :cartwheel: :
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5167.JPG)

Turning a boss on the end of that was easy, and then I drilled a 7mm hole through the needed length.  This hole is 1mm under-sized - the crankshaft is 8mm in my build, but I'll bore the hole out to 8mm later on in the build.  It leaves enough space to start boring, but enough "meat" to ensure a good concentric shaft hole to make the flywheel run nice and true, even if some minor miss-alignments occur later on.  I installed the dividing head on the mill and transferred the chuck to it.  I used the edge finder and DRO to locate the center of the workpiece, as well as the edge on the end.  From "experience" I know that cross-drilling items mounted like this a bit further out from where the dividing head is mounted in the vise can make it tip or flex enough that alignment is lost.  So I devised an impromptu screw-jack for support from some bits from the clamping kit.  Crude, but effective:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5168.JPG)
You might just notice the "safe" location I stored the 4-jaw chuck and ring...

My dividing head has a 60 tooth worm wheel, so to get the eight spoke locations I have to index it around 7.5 turns for each location.  That's easily done on any even-numbered hole circle, so I chose a convenient one (38 holes) and set the fingers to reflect the half-turn.  Could just as well have used a permanent marker to mark the two opposing holes, but I've gotten used to using the index fingers. 

Then I set up a little "to-do" list consisting of: "1) Remove screw-jack.  2) Index to next hole location.  3) Spot drill hole location.  4) Drill 4.2mm hole ~8mm deep with drop of cutting oil.  5) Drill 5mm hole ~1mm deep.  6) Put mill gearbox in "neutral".  7) Chuck up M5 taper tap, add drop of tapping fluid and tap hole using quill feed arm to apply light positive pressure, turning chuck by hand till it just tightens at the bottom of the hole.  8 ) Chuck up M5 bottoming tap, and follow same steps as for #7, but take care when starting the thread so that it engages the previous thread.  9) Repeat".
The "to-do" list worked well - even though it is usually frowned upon to chuck up taps in a drill chuck for tapping  :-[ .  I really need to make some tap guides to supplement the tailstock die holders.  The plans don't show detail on how to actually hold the flywheel to the crankshaft.  That's left to each builder's own preference.  I decided on two M3 grub screws (set screws for those in the USA).  It's not the neatest solution, and I don't know how the 12" to the foot engines' flywheels were secured, but it's worked for me in the past.  Even a small deviation caused by a single grub screw can make the flywheel wobble, so I settled for two in-line - so that they apply clamping force in the same direction.  As long as the bore in the hub is true and a good fit to the crankshaft, this should give the best results IMHO.  Unfortunately, after drilling and threading the first grub screw hole, I had a brilliantly stupid moment. The first hole was offset 6mm from the hub center line, and I went and spotted the second one at 8mm offset  :censored: .  After re-spotting it at the wanted 6mm offset and drilling and tapping, I had this less-than remarkable lot:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5169.JPG)
 :headscratch: Re-make the hub or recover from the boo-boo ? - I decided on recover...

Seeing as the rotary table was set up, I also finished off the inner hub - much simpler to-do: "1)index to location.  2) Spot drill.  3) Drill 5mm. 4) Repeat".  It was close enough to the dividing head's mounting in the mill vise that it wouldn't move easily, hence no support from a screw-jack needed, as long as I didn't get too heavy on the drilling feed:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5170.JPG)

I then spent some more time turning the hub.  To make the boo-boo I made earlier on "go away" I turned another step on the hub to clear it.  Then I sawed it off slightly over-length, re-chucked and turned a mirror image on the other side:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5171.JPG)

The completed hub - without any additional filing/emery work or anything.  Not brilliant, but shiny as-turned, and even if not quite to plan, I'm a happy chappy with the result:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5172.JPG)

Next I sawed some ~80mm long lengths of a bit of 5mm diameter silver steel rod.  I'd have preferred to use ordinary steel rod for this; the silver steel is a bit of a waste, but I had the silver steel in stock and not something cheaper.  One end of each section was threaded M5 with the tailstock die holder, and to clean the inevitable "raised"  section left after threading, I used a small file to remove the burr on each workpiece:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5173.JPG)

A test-fit in the hub, and things looked OK:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5174.JPG)

So I decided to assemble the lot...  With the hub supported by the tailstock, the spokes were screwed in - with retainer added to both the threads and the bits going through the rim.  I supported the hub on most of the un-fluted section of the 7mm drill chucked up in the tailstock chuck.  Things went together very well with copious amounts of thread retainer mixed in, and each spoke tightened down with a pair of pliers.  I'll let that lot "Go off" to paraphrase our U.K. kin. :
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5175.JPG)

Hopefully more next weekend...

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: Don1966 on June 03, 2013, 03:42:30 AM
Nice save and nice set up. Your moving along pretty good Arnold. Even though you spent a whole day on the flywheel thats still good progress. Your dividing attachment, is it a myford orginal or built one? Just curious, looking at it seems to be the old style VDH.

Don
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on June 03, 2013, 05:29:08 AM
I already see a very nice flywheel. 

Good save there with the hub by making that step.  Actually you made it to plan because there was a step in the plans.

I have been thinking of how to fix the flywheel to the shaft.  I am trying to avoid if possible grub screws.

Quote
even though it is usually frowned upon to chuck up taps in a drill chuck for tapping

Don't worry Arnold, I do that all the time.

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: Jo on June 03, 2013, 07:46:07 AM
Looking better every time I see it Arnold  :ThumbsUp:

The otherway to attach the Flywheel is to key it "on to" the shaft. My S&P flywheel is attached using a saddle key that does not actually go into a groove in the crankshaft but that follows the radius, then the outer edge is tapered so that when it is tapped home it tightens the flywheel onto the shaft  ;)

Jo
Title: Re: Arnold's take on the MEM Corliss
Post by: Maryak on June 03, 2013, 08:46:42 AM
Arnold,

Great Flywheel  :NotWorthy:

Generally speaking Flywheels are keyed to shafts, sometimes with a Woodruff key, sometimes with a blind keyway in the shaft and sometime with a through keyway from the outside of the shaft to the back of the wheel hub and a gib type key. With the exception of the gib key some form of axial locking of the wheel is still required. IMHO a couple of grub screws is an effective way of achieving both on model engines, especially if the screw locates on a bit more than a dimple in the shaft.

Best Regards
Bob
Title: Re: Arnold's take on the MEM Corliss
Post by: b.lindsey on June 03, 2013, 11:21:08 AM
Nice save on the hub Arnold. And the spokes look terrific. Should make for a beautiful flywheel indeed!!

Bill
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on June 03, 2013, 07:11:42 PM
Thanks for checking in all  :praise2:

Don, the dividing head is a Myford original - with it's tailstock and the two standard supplied plates.  Seems like the new ones haven't changed much - Myford Website (http://www.myford.co.uk/acatalog/Myford_Dividing_Head_and_Plates.html), but I nearly had a coronary when checking the price for the additional plates - I only have number 1 and 2, but on occasion the other two would have been handy.  At some point I'll get some bits of plate and start making up the missing ones; I have a mad idea that there might just be a use for old CD's to make templates to in turn generate fairly accurate home-brew dividing plates  ;)

Vince, it does have a step in the plans - mine now has an extra step - we'll call it "customisation".  I was also not too keen on using the grub screws; should have asked first  ;)

Jo, Bob, thanks for the ideas for mounting flywheels :ThumbsUp: 
I'll mill some flats on the crankshaft later on for the grub screws to have a better seat - but that have to wait for the base to get sorted out so I can get the correct location on the crankshaft.

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: ozzie46 on June 03, 2013, 09:06:10 PM
Way to go on the hub recovery Arnold.  Neat fly wheel.

 Ron
Title: Re: Arnold's take on the MEM Corliss
Post by: Tennessee Whiskey on June 03, 2013, 10:17:39 PM
If I may pose a question on the flywheel attaching. Back when I was working in one of my Dad's millwright crews we installed couplings on pumps and motors. They were all keyed,but, they were all shrink fitted, I guess thats what it's called, we called it sweating on a coupling. For what our engines do, would this type of fitting not be strong enough? I know if you were the unlucky soul that stuck one before you reached depth it was pure Hell getting it off. Just wondering :headscratch:

Eric
Title: Re: Arnold's take on the MEM Corliss
Post by: Captain Jerry on June 04, 2013, 01:38:16 AM
Arnold

Nice job with the spokes.  I have done it in my head many times but even there, it doesn't come out as good as yours. As has been said, these big flywheels were usually fitted to the shaft with keys, and on very large ones as many as four keys were used.  On I.C. engines, a key is necessary, even on small models engines, to handle the impact loading of combustion.  On a slow revving steam/air engine there is a much smoother power stroke.  Grub screws (always on flats) should do the job just fine.  If the screws are not seated on flats, the small scar that they put on the shaft surface may make it near impossible to remove. DAMHIK!

Jerry
Title: Re: Arnold's take on the MEM Corliss
Post by: larry1 on June 04, 2013, 02:12:37 AM
Arnold,  Great job,  Truly like to see you work, you make it look so easy.        larry1
Title: Re: Arnold's take on the MEM Corliss
Post by: swilliams on June 07, 2013, 05:07:20 AM
The flywheel is turning out great Arnold

Slow going but looks like you're having alot of fun. Loved the photo where you've only got 0.7mm bed clearance.

Cheers
Steve

Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on June 08, 2013, 08:42:44 PM
Ron, Eric, Jerry, Larry & Steve, thanks for checking in Gents  :praise2:

Eric, shrink fitting can be useful in our hobby; I've used it to fit flywheel rims to spoke hubs like this one (http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_3452.JPG), but in general most models require the flywheel to be removable from the shaft for assembly and maintenance.  On this specific build, one would have to have split-bearings if the flywheel was heat-fitted to the shaft, and as you mentioned, it can be a tricky operation.  With the smaller parts, the heated bits cool down much quicker, so getting one's timing right could be a major pain.

Jerry, I've also built it in my head...  While I have made similar style, but much smaller flywheels in the past, I have had problems with the drill bits wandering.  This turned out to be much easier to do in the bigger size with steel than the bronze concoctions I've made.
You're right; a flat is usually needed for grub screws to seat on, but I have also cheated a bit in the past by filing the tip on the grub screw flat to clear off the bluing, and then applying a small ball of lead-based electronics solder to the tip.  The solder easily takes to the tip of the grub screw, and when tightened on the shaft does not mar it. The lead has a fairly high coefficient of friction, so keeps the flywheel on very well.  As you mentioned - for steam, hot air and Stirling engines only.  I have yet to build an IC; I love to look at others' IC engine builds and see them running, but for my own builds, there's only about two that I'd like to build.

First off, I used a junior hacksaw to saw off the spoke stubs as close to the rim as possible.  Turning them down would have taken ages, and the interrupted cutting could easily throw off the carefully clocked up rim:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5187.JPG)

Next there was a major scare in today's shop session - not at all physically dangerous, but I nearly crapped myself, and Shrek the parrot definitely knows a couple of words now that he shouldn't have overheard  ::).  When I started up the lathe motor, it went clickyclickykgrrr, and all the electricity in the shop went off...  The lathe's motor shouldn't make that noise; on my lathe it just should start up with a gentle "clickWhump" sound (amplified by the lathe cabinet) and run with a quiet hum.  Checking the electrical switchboard in the shop, the earth leakage breaker had tripped.  I thought the motor had gone bust, so with great trepidation I unplugged the lathe, switched on the earth leakage, and still no power in the shop.  Back to the house and my main DB which feeds the shop, and that earth leakage breaker had tripped as well.  Switched that one on, and power was back up.  So, definitely something wrong with the lathe's motor - that's when Shrek learned the new words; there is no way I can afford a new motor for the lathe right now.
After I cooled down a bit, I started pulling things apart.  There's no photos of this lot; the camera was the last thing on my mind.
Once the motor was off the lathe I opened it up - and there I found it; one of the bits of spoke I'd sawn off earlier had somehow found it's way into the motor  :o and caused a short-circuit.  After checking all the bits through and a general clean-up, I couldn't see anything else amiss, except for some wear on the bushes, and the rubber mountings are definitely starting to perish.  Rob Wilson once told me these Brook-Crompton motors fitted to the Myfords are "bullet proof", so I assembled the lot up again, and started her up...  "clickWhumpHummmmmmm"  :whoohoo: - back in business, albeit two hours later.  Not bad for a fourty-odd year old motor either.  At least I know the earth leakage breakers also still work as expected; it's been a long time since those were tested, and overdue.  And I need to make a guard for the motor...  Hmm... on the subject of safety, all the fire extinguishers need their annual 3rd party service as well - I make a point of up-ending the powder extinguishers one a month to keep the powder loose.

With the lathe drama sorted, I got back to machining, and turned the excess off the spokes - with very fine cuts; just 5 thou infeed at a time and dead-slow while feeding the carriage.  Once the rim was reached, I upped the carriage feed a bit, and turned it down to the point where the outer rim "just" started to fit - keeping the finish on the outside of the inner rim intentionally very rough:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5188.JPG)

Next I assembled some bits together:  A bit of flat wood off-cut from kitchen renovations a couple of years a go, a bit of wood to use to tap the inner rim into place without marring it, a hammer, and a bottle of retainer:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5189.JPG)

I smeared the inner rim with retainer on the outside; the coarse finish I left on it allowed a space for the retainer to sit while gently knocking it into place.  I also smeared the inside of the outer rim with retainer, then used the hammer and wooden stick to knock the lot together; gently going around in a circular fashion till the inner rim settled against the ridge I left in the outer rim.  This formed a combination of a press-fit and a "Loctited" fit; plenty strong enough for this job.  It might fly apart at 8000rpm+, but this engine should never reach those kinds of speeds; in fact, anybody trying to run it at over 1000 rpm should be flayed alive and then drawn and quartered.  I'll be quite happy if I can get it to run at about 60rpm or less.  Anyway, I ended up with this lot:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5190.JPG)

When I drilled the hole in the hub earlier, I left it at 7mm, rather than the final 8mm needed to fit the crankshaft.  I did that on purpose, so that I could finish-bore the shaft hole once the flywheel was assembled to compensate for any minor miss-alignments.  So as a last step, I clocked up the flywheel in the 4-jaw chuck again gripping and clocking on the outer rim.  None of my small boring bars had enough reach to bore through the entire hole, so I used a 6mm end-mill offset at a very small angle axially from the lathe center line, and with one cutting tip on center height to bore the hole to size:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5193.JPG)
First time I used this method, but it worked very well indeed  :cartwheel:

The finished flywheel:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5196.JPG)
You'll notice some marks on the inner rim from chucking it up.  Those will be invisible once it's painted - though I could apply some elbow grease with emery to get rid of them.

At least it seems to run true:
http://www.youtube.com/watch?v=dtjzRiD_mUw

It's not often I say this, but I'm pretty well pleased with how it's turned out.  In fact, there's a bit of my braincell that's screaming at me not to paint the flywheel... 

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on June 08, 2013, 09:08:45 PM
Very, very nice looking flywheel Arnold.   :praise2: :praise2: Even better than mine.

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: Chris J on June 08, 2013, 10:03:49 PM
Great work & a great thread - Thanks  :ThumbsUp:
Title: Re: Arnold's take on the MEM Corliss
Post by: Don1966 on June 08, 2013, 10:18:36 PM
Nice job on the flywheel, it came out great. I love it's look also.  :ThumbsUp:
Nice save on the lathe motor, be thankful for the earth fault breaker it saved your motor. Without it there would be a hole in your winding.

Don
Title: Re: Arnold's take on the MEM Corliss
Post by: Florian Eberhard on June 08, 2013, 10:24:12 PM
You'll notice some marks on the inner rim from chucking it up.  Those will be invisible once it's painted - though I could apply some elbow grease with emery to get rid of them.

You could have avoided this easily by using some paper between the chuck and the flywheel. If you use the paper from the same sheet, the thickness of all of the paper pieces is exactly the same.
Or also small pieces of brass sheet - that works pretty well for claming such stuff.
I have never used it but I have heard of people using aluminium foil (from the kitchen) to underlay.
Also, Aluminium foil is within a very small tolerance and therefore suitable for this.

Cheers Florian
Title: Re: Arnold's take on the MEM Corliss
Post by: Maryak on June 08, 2013, 11:38:03 PM
Arnold,

Fantastic Flywheel  :NotWorthy:


You could have avoided this easily by using some paper between the chuck and the flywheel. If you use the paper from the same sheet, the thickness of all of the paper pieces is exactly the same.
Or also small pieces of brass sheet - that works pretty well for claming such stuff.
I have never used it but I have heard of people using aluminium foil (from the kitchen) to underlay.
Also, Aluminium foil is within a very small tolerance and therefore suitable for this.

Cheers Florian

Free Advertisment....................A Coke Can can provide heaps of protective bits for many and varied interfaces. (Or aluminium canned beverage of your choice) and you get pleasure from removing the contents before use. ;D

Best Regards
Bob
Title: Re: Arnold's take on the MEM Corliss
Post by: Bearcar1 on June 09, 2013, 12:26:42 AM
To your high standard of work as usual Arnold. A terrific looking flywheel in the end. I really like the round spokes approach, but that is just my personal taste and amounts to only that. Glad to hear that Shrek is OK and is obviously wondering what it was you said and is practicing up for a time you least want it to happen to utter them clearly.  :lolb:


BC1
Jim
Title: Re: Arnold's take on the MEM Corliss
Post by: swilliams on June 09, 2013, 12:50:47 AM
It's turned out really excellent Arnold  :praise2:

So what are the two IC engines you'd consider building?

Steve
Title: Re: Arnold's take on the MEM Corliss
Post by: Tennessee Whiskey on June 09, 2013, 12:56:02 AM
Arnold, that's sweeter than blackberry jam. Beautiful flywheel :NotWorthy:

Yo Redneck,
Eric
Title: Re: Arnold's take on the MEM Corliss
Post by: Alan Haisley on June 09, 2013, 01:21:07 AM
Really smooth, Arnold.
Alan
Title: Re: Arnold's take on the MEM Corliss
Post by: Stilldrillin on June 09, 2013, 09:17:38 AM
Superb flywheel, Arnold!  :Love:

David D
Title: Re: Arnold's take on the MEM Corliss
Post by: gbritnell on June 09, 2013, 12:43:43 PM
Hi Arnold,
Great job on the flywheel. As to your comment on whether to paint it or not, I went through the same thing when I built my Holt engine. The natural metal looked so industrial that I left it unpainted. The only problem down the road might be in preventing some type of corrosion from the bare metal.
gbritnell
Title: Re: Arnold's take on the MEM Corliss
Post by: b.lindsey on June 09, 2013, 02:04:48 PM
Fantastic job Arnold....i knew where you were going with the flywheel but it looks even better that i imagined.  Personally, I would leave it unpainted, but whatever you do won't detract from its beauty at all!!!

Bill
Title: Re: Arnold's take on the MEM Corliss
Post by: steamer on June 09, 2013, 02:05:34 PM
Painted or otherwise....looks fantastic!

 :NotWorthy: :NotWorthy: :NotWorthy:

Dave
Title: Re: Arnold's take on the MEM Corliss
Post by: Chris J on June 09, 2013, 04:25:36 PM
Is there some kind of lacquer that could be sprayed on to keep the look and preserve the metal ?
Title: Re: Arnold's take on the MEM Corliss
Post by: mklotz on June 09, 2013, 04:48:15 PM
Is there some kind of lacquer that could be sprayed on to keep the look and preserve the metal ?

Recently someone put me on to Renaissance Wax...

http://www.amazon.com/Picreator-Renaissance-Wax-200ml/dp/B0012S1XBO/ref=sr_1_2?ie=UTF8&qid=1370792041&sr=8-2&keywords=Renaissance+wax

which is used by museums and such to protect frequently handled metallic objects such as swords and armor.  Some shooters are also using it on their guns in preference to the old standby, Flitz.

As a test, I polished some brass and steel display items and then waxed them with this product.  I left them out on a bookcase and fondle them as I walk by every day.  In over two months of exposure, the shine hasn't diminished and the items are not marked by fingerprints.  Also, the steel feels smooth and slick to the touch-very sensuous.

I don't polish engines because I think "bling" looks trashy on an industrial item.  Nevertheless, I'm sure this stuff would work well on engines. 

$26 for 200 ml is pricey.  Amazon sells a 65 ml container for $16.

http://www.amazon.com/Renaissance-Wax-Polish/dp/B003AJWN62/ref=sr_1_1?ie=UTF8&qid=1370792041&sr=8-1&keywords=Renaissance+wax

Give it a try.  Even if you decide not to use it on your engines, you can earn some real points with SWMBO by waxing her candlesticks.
Title: Re: Arnold's take on the MEM Corliss
Post by: b.lindsey on June 09, 2013, 05:23:49 PM
It sounds really   good Marv, and if so, wouldn't getting over three times as much for less than twice the price be worth it?  Flitz isn't cheap either but I find it less than satisfactory.

Bill
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on June 09, 2013, 07:29:35 PM
Thank you all for your kind comments and checking in  :praise2:

Jim, you nailed it with Shrek coming out at the worst possible time with newly-acquired words...  African Greys have a knack for embarrassing their owners, and it's extremely difficult to "un-learn" them  ::) .  Overall though, he's a good little birdy  :)

Steve, the definite one is Gail Graham's Lobo Pup.  The other would be a hit and miss; I'm leaning towards the Tiny.  A working IC model of a Lister D type might also make the list.

As to painting the flywheel - the rest of the model will be painted, and the flywheel is already a prominent part.  It'll be a bit overpowering if left unpainted; I'd rather make the valve train appear a bit more prominent when the engine's done; that's where this engine's true essence lies for me.

I was looking forward to a good shop session today, but a call-out to a customer dashed that.  I did get a bit done though; with the flywheel done, I really wanted to see how things looked assembled, and that meant I had to do a bit of woodwork.

The mounting hole locations were all marked on the base, and then I drilled the holes with the drill press.  Jim (BC1) mentioned earlier in the thread that the teak I'm using is oily, and that causes the flutes on the drill bit to clog up quite quickly while drilling.  The wood is fairly thick, so I peck-drilled and brushed off the clogged up wood from the drill bit regularly with a small brass brush.  Tempting as it might be to just hold down the workpiece on the drill table for a job like this, it's always better to clamp it up:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5198.JPG)

While drilling the holes, I heard a bird-call outside the shop that I didn't recognize.  It sounded a bit like an eagle, but up in the tree was this pretty male Grey Hornbill:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5200.JPG)
I haven't seen many of those around; they are plentiful in other parts of Africa, but central Namibia is literally on the outside edge of their main habitat.

To make the flywheel cut-out, I cobbled together bits from the clamping kit, opened the mill vise to maximum, added a suitable spacer on top of the rotary table's table to make the base lay flat across the vise jaws and on the rotary table, and clamped things down as best as I could.  A bit Rube Goldberg, but it worked:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5201.JPG)

The four corner locations was drilled with an 8mm drill, leaving some room for finishing to size, then I used a 12mm carbide end mil to start taking out the excess:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5202.JPG)
With the ill flat-out at 1200rpm, this was a breeze.

Once the excess dropped out, I ran the mill around all the edges, opening them up to final size:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5203.JPG)

Now it's starting to look like an engine  :)   I'll have to make up or invest in some more fasteners though; things are mounted very loosely here:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5204.JPG)

(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5205.JPG)

Just for fun, I perched my version of Elmer's Tiny on top of the flywheel - these make up my smallest and biggest builds to date:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5207.JPG)

Things are still slightly stiff, but it's a good feeling to flip over an engine for the first time:
http://www.youtube.com/watch?v=k9oszK0OMEE

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on June 09, 2013, 07:44:47 PM
WOW.  Now it is really taking shape.  Thanks for showing it mounted on the base.

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: Kim on June 09, 2013, 09:03:35 PM
Hey Arnold,
Very impressive to see it on its base, even if only temporarily mounted!  Your Corliss is really looking good  :praise2:

And the Grey Hornbill was just an added bonus. I've never seen a Hornbill, gray or any other color for that matter! :)

Kim
Title: Arnold's take on the MEM Corliss
Post by: NickG on June 09, 2013, 09:06:31 PM
Flywheel looks awesome Arnold - was just going to say its almost a shame to cover it up with paint. With a casting you want to hide the mess but it will hide some of the great workmanship here. Then again - look at Jason's painted one on his grasshopper - looks spot on and sure this will too.
Title: Re: Arnold's take on the MEM Corliss
Post by: Don1966 on June 09, 2013, 09:08:01 PM
Awesome Arnold, she's shaping up nicely. It shouldn't be to long now before she's up and running.  :praise2: :praise2:

Don
Title: Re: Arnold's take on the MEM Corliss
Post by: b.lindsey on June 09, 2013, 09:12:07 PM
Fantastic Arnold, I would have to say it was a productive day after all!!!

Bill
Title: Re: Arnold's take on the MEM Corliss
Post by: sbwhart on June 10, 2013, 07:34:38 AM
Looking extremely good Arnold

Are you going to put some fancy rebating around the edge of the wooden base, if so be carful of the edges splitting when you go across the end of the grain, I've fallen foul of this in the past,  best to take the across the grain cut first then you have a chance to clean the split away when you take the cut with the grain, or if you can grip the wood close to the edge so that you give it some support to stop it splitting.

Looking forward to the nest instalment

Stew
Title: Re: Arnold's take on the MEM Corliss
Post by: NickG on June 10, 2013, 08:03:30 AM
When I posted my last reply I hadn't seen your assembly pics and vid - mustn't have displayed properly on the phone. Wow!   :ThumbsUp:

Does the engine have a metal base too or is everything to be bolted to the wood as per pic? Turning over nice and freely - half the battle.

Nick
Title: Re: Arnold's take on the MEM Corliss
Post by: EmanMyford on June 10, 2013, 10:39:30 AM
Hi Arnold, the engine is looking great! :cheers:
Its only when you showed Tiny on the flywheel when I realized the scale.

Kind Regards.
Ewald
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on June 10, 2013, 09:10:18 PM
Thank you all who checked in  :praise2:

Vince, I'll be keeping things on the simple side from now - the interesting bits are coming up, and I'd like to pick up problems if they arise.  You keep on with your build; it will turn out much prettier than mine  :ThumbsUp:

Kim, this Hornbill is completely bland compared to other species over the world.  The rest in Namibia aren't that colourful either; they just have yellow to bright orange beaks depending on the species.  I'm surprised that you don't have some native species in Oregon  :o .  Anyhow, if you stick in "hornbill bird images" in Google, you'll see what I mean, though there are very few images of the one I sighted...  It may be rarer than I thought - or so common in its more habitual areas that no-one bothers to photograph it.  In case no-one have guessed it yet, I do like birds very much; be it from the Avis or Homo Sapiens lineage  :naughty:

Don, there's still quite a lot to do, so don't get your hopes up too soon.  The valve train will take quite a bit of effort; even though it's down to some of the smaller sizes I'm used to working with, it will still be challenging.  Vince and Jerry already mentioned some of the tricky stuff that's about to come up...

Stew, yes, I'll be firing up the router at some point to trim up the edges, and like you mentioned, across the ends first and then length-wise.  The base still needs quite a bit of height added as well.  I'm out of wood for that, so it's a question of buying more wood to add on, or make some kind of raised and covered platform from whatever bits I can find, or just add some ornamental feet to raise it and leave the bottom exposed...  Choices - choices  :shrug: .  For now, I'll focus on finishing the basic engine and get it running  :ThumbsUp:

Nick, there's no other base; it will get mounted straight to the wood.  It's turning over OK, but the piston still needs a ring,  and the piston rod pack nut needs packing.  Both these will tend to tighten up things.  On the other hand, the cylinder bore must still be lapped, which will ease up friction with the piston ring.  I've found that its easier to get a runner by checking things as one's going along and sorting out any minor problems that might arise along the way - like I had with the connecting rod catching against the cross-head guide.

Thanks Ewald  :cheers: .  Actually, if I removed some of the excess length from Tiny's crank shaft and the crank pin, it would fit inside the cylinder bore of the Corliss  8)

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on June 15, 2013, 07:59:17 PM
Well, not much progress today.

The last bit that needs to go on the crankshaft (for now) is the eccentric.  Once that's done, I can mount things a bit more permanently and get to work on the valve train.

This is pretty much a duplicate of Vince's post - I didn't have stainless for the eccentric though, so I made it from mild steel.
A simple turning operation.  To make the groove, I ground up and honed the end of a bit of 4mm square high speed steel to make a form tool; my parting tool is inclined to flex too much for this kind of job:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5211.JPG)

Off to the mill, and I drilled the hole for the crankshaft:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5213.JPG)

I used the band saw to saw off the eccentric, and faced the sawed side to length:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5214.JPG)

The last step was to drill and tap for the grub screw:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5215.JPG)

One finished eccentric after some de-burring; it looks vaguely familiar  ;) :
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5219.JPG)


In Vince's thread I mentioned that I was thinking about how to go about making the different rods in the valve train adjustable...
My first thought was to use BA threads on one side and Metric on the other for each of the rods.  Unfortunately this won't quite work; at the closest equivalent sizes their thread pitches are near-identical, so won't work.  I'm in no position to order other types of taps and/or dies from overseas at the moment either - the N$ is pretty worthless right now on international currency markets  :(

So I guess it'll be the slightly harder way for me.  I've done quite a few 0.5mm pitch threads; that's not hard to do on thicker bits; my boring head has an M6x0.5mm home-brew leadscrew, and I also made an M4.5x0.5 tap that works really well.  Time to see if I can make a couple each of M3x0.5 and M2x0.4 Left Hand taps in taper and plug form...
 :thinking: Wonder If I'll be able to get down to M1.6x0.35 LH...
Single-point screw cutting the different rod ends to match the taps wouldn't be hard to do if once I can make the taps.  I've never tried to make my own dies; that might be a bit more difficult in these smaller sizes, so will have to wait.

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on June 15, 2013, 09:24:10 PM
Always look forward to your weekly update Arnold.  Like you, I haven't done much this week.

Regarding the rod adjustment, I have come to the conclusion that it is better to leave it till later and see if it is actually required.  I think that if I silver solder the clevis side, I might still have some adjustment leeway with the 3mm x 0.5 thread on the other side.  Still not sure about it and that is the reason I am leaving it until other parts are done.

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: Maryak on June 16, 2013, 01:39:43 AM
Nice work as always Arnold, :praise2:

Vince,

Unless I'm misunderstanding, if one end is fixed then I think the adjustment is limited to half turns to line up the other end.................???

Best Regards
Bob
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on June 16, 2013, 04:49:24 AM
Yes Bob you are right and every half a turn it moves in or out (depending which way one turns it) by 0.25mm.

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on June 16, 2013, 06:51:12 PM
Thanks Bob & Vince  :)

Vince, you're quite right; it may not be needed to add additional fine adjustment.  Between the "differential" created by the pivot arm for the main rods, it may just be possible to use adjustments on either side; adjusting on the eccentric side by 0.25mm will make the other rod move more than that, but then, on the other rod, the adjustment is pretty much "infinite", as it's connected to the valve disk using the pivot and a grub screw...  So no need to really faff around too much  :)
As for adjusting the rods going from the disk to the valves, this is also not really needed; one only needs to turn the valve in the arm that connects the rod to it.  I think we're over-complicating things  :Lol:

I started work on the eccentric strap today.  Digging around, I could not find suitable material to make it from as a whole part, so I settled on making it as an assembly.  I had a bit of suitable phosphor bronze bar on hand to make the "round" section from; it's slightly smaller than the plans, but should be fine.  I cleared the skin off it on the lathe:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5220.JPG)

Next on to the mill, and I drilled a 5mm hole about 4mm deep into it, as well as touched a 4mm end mill on either side to form shallow pockets:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5222.JPG)

I turned up and threaded a short section of brass rod to 5mm OD and M3 on the inside, and then drilled a 2mm hole into a piece of 4mm brass and parted of two 6mm long sections:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5223.JPG)

Some Silver Soldering done:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5224.JPG)

I didn't bother to pickle that lot to get it totally clean; just enough to get rid of any flux left.  Then onto the mill again, and I used a 0.5mm slitting saw to run through the center:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5226.JPG)

The workpiece was placed vertically in the vise, and I used the height gauge to set the slitting saw height to chop off the top:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5227.JPG)

I ended with this lot for the day:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5229.JPG)

In my next shop session I'll stick that lot in the 4-jaw chuck and bore it to size.  The 0.25mm either side that it's "out of round" from using the 0.5mm slitting saw will be barely noticeable, and some judicious strokes with a file will hide even that.  Right now it looks a bit rough, but it should come out OK once finished.

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: Jo on June 16, 2013, 07:08:15 PM
Looks good Arnold.

Did you get over enthusiastic with your silver solder at one point there  :???: The way around it is to cut off a small piece and lay it in the flux then apply the heat. That way you can control the amount of silversolder and have less to clean up after, it does not stop you poking  :stickpoke: a bit extra in if you feel the need  :D

Jo
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on June 16, 2013, 07:10:01 PM
I am seeing a nice strap there.  I am really enjoying this.  Seeing the same parts being made in a different way.  Really educational.

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on June 16, 2013, 07:36:22 PM
Thanks Jo.  You're dead on the money; a slight bit of inattention and I'd tapped the rod in the wrong spot.  I still have problems with cutting bits of and placing them; when the flux starts to bubble the bits go all over the show and away from the joint  :???: .  I still need to get some of that thin silver solder available overseas.  Once I have a bit of a stash built up I'll order in, but for now, the stash is depleted as I still have to pay import duties and VAT on a new "toy" that should be arriving in the next couple of weeks...

Vince, thanks.  Yes; we're all building the same "thing", but in different ways.  No mass-production here; one-off originals for each and every person who builds something  :)
It's all part of the fun of this hobby; there's just some basic "rules" and after that everyone can do as they see fit with whatever they have available  :ThumbsUp:

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: Jo on June 16, 2013, 07:47:20 PM
I still have problems with cutting bits of and placing them; when the flux starts to bubble the bits go all over the show and away from the joint  :???: . 

Start by just warming it slowly to get the flux to dry and you will find it will stick the solder to the joint. I normally make little loops around the things I am sticking that way they don't go walk about. The other thing worth sometimes doing is flattening out the bit of silver solder with a hammer ;)

Jo
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on June 23, 2013, 08:35:35 PM
Thanks Jo; I'll give that a try as well  :) .  One thing I keep forgetting is to try and make up my own "silver solder paste" by filing a bit of solder down over a bit of paper to catch the filings, and then mixing it with flux.  Have to experiment with that one as well at some stage...

Yesterday was a lost cause; I had to pay attention to other matters, but today I got some more bits done.  First of was more work on the eccentric strap; first, I marked the center:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5230.JPG)

Then clocked it up in the 4-jaw, taking care not to be too heavy-handed while chucking it up:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5231.JPG)
 ::) I REALLY need to make a pump-center...

I very carefully drilled it out to 10mm - keeping the feed rate low to prevent the drill "grabbing" in the bronze , and from there used a small sharp boring bar to bore it to final size.  The eccentric ended at 22.05mm, so I bored this to 22.1mm to give a bit of room to form the bearing surface:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5232.JPG)

Not exactly a thing of beauty after clean-up, but it will do for now.  I'll make smaller nuts; the standard M2 nuts are too big:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5233.JPG)

It turned out to be a very nice fit on the eccentric; turning smoothly, but without discernible play:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5234.JPG)

Next, a bit of 2mm brass plate for the lever arm.  The plans call for 1.5mm, but I had a choice of 1.2 or 2mm, and the 1.2 could be a bit flimsy, so I went with the 2mm.  Holding smaller bits of plate like this for drilling can be problematic, but it's a breeze on the tooling plate I made:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5235.JPG)

Some rounding-over and a bit of clean-up, and the lever was done.  the bigger 3mm hole on the one end is not exactly to plans; I made the thread in the base for the pivot M3, hence the larger hole:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5236.JPG)

Like Vince mentioned, the forks for the two eccentric rods are identical, so I also made them as a pair from some 12.7x4.7mm (1/2" x 3/16") brass flat bar I have.  I used the edge finder to find the middle of the bar on the Y-axis, and the end on the X axis.  I started to mill the center out wit a 2mm slot drill, but after I reached about 5mm deep, it snapped...  On the 6mm deep level, another one snapped, even though I was very careful with the feed-rate.  Not wanting to break my entire supply of 2mm mills on these pieces, I decided on another tact.  I set up the vise stop so I could flip the workpiece upside-down, and drilled and tapped the M3 holes for the rods - leaving 1mm additional gap between them for a 1mm slitting saw to slit the two bits apart:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5237.JPG)

Then I slit off the two still-joined pieces from the parent stock at the needed length, and once again reverted to the tooling plate; clamping down securely on the end of the workpiece in the area that would not get material removed.  I didn't want to have the workpiece come loose once I started removing material.  I finished the slots with a 1mm slitting saw (that's the thickest I own) - one cut top and one cut bottom:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5238.JPG)

Then I slit the pieces apart - leaving the tiniest little burr keeping them together.  It saves having to play hide-and-seek on the shop floor to find the workpiece as it gets flung away if fully slit off... :
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5239.JPG)

Some more rounding over and clean-up, and I had the two forks.  I just noticed there's still quite a big scratch left on the right-hand one  ::) :
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5240.JPG)

A bit of 3mm stainless steel volunteered to get threaded either end with a tailstock die holder, and I had one eccentric rod.  I intentionally left it slightly long at this point:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5241.JPG)

The results of today's work assembled together.  Broken slot-mill shanks makes nice holding-together pins  :LittleDevil: :
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5242.JPG)

I couldn't leave it at that, so I disassembled the engine a bit first.  When I made the bits of the frame, I didn't tap the one bearing mounting hole, nor the thread for eccentric pivot, so I quickly, but carefully, did those.  Then I loosely assembled things again, with the eccentric set roughly at 90o to the crank, and checked how far the eccentric lever pivoted to either side from "straight-up" while turning the flywheel.  As mentioned earlier, I left the eccentric rod a bit long.  I had to shorten it by another 2mm and add four turns of thread to the eccentric rod, and things ended up pivoting evenly and equally both ways by eyeball MK1.  That should just about do for adjustments on "this" side of the eccentric pivot.

From a top assembly view, you can see that I need to move the eccentric slightly more toward the flywheel to get it in it's correct place:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5243.JPG)

The pivot rod is pretty much upright at the full piston travel to either side of the cylinder:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5244.JPG)

Still crude, but it's slowly starting to resemble an engine  ;D :
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5245.JPG)

One thing I would do differently if when I have to do it again is for the screws/bolts on the eccentric strap.  Rather than drill clearance through both parts to use a bolt or screw with a nut, I'd drill through the "flywheel side" for clearance, but tap the "engine side".  It was a real bugger to get the bottom nut into place for installation; I eventually resorted to contorting my index finger with a dab of grease on it to hold the nut in place through the flywheel to get the nut into position. Once I make the smaller nuts, that will be a heck of a load of "fun"!

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: Jo on June 23, 2013, 08:44:26 PM
Nice Arnold  :ThumbsUp:

Best to avoid those very small suicidal milling cutters if there is some way to get a slitting saw to do the job  :D.

Looking forward to seeing your pump centre come together it is only a 10 miniute job..

Jo
Title: Re: Arnold's take on the MEM Corliss
Post by: b.lindsey on June 23, 2013, 08:47:31 PM
Another wonderful update Arnold. The ecentric strap looks perfect as does the assembly shot...nothing crude about any of it...lovely work on every part!!

Bill
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on June 23, 2013, 08:56:37 PM
Nicely done Arnold.

Vince
Title: Arnold's take on the MEM Corliss
Post by: NickG on June 23, 2013, 09:43:33 PM
It's looking great Arnold, thanks for the update.
Title: Re: Arnold's take on the MEM Corliss
Post by: Captain Jerry on June 23, 2013, 09:47:51 PM
Nice work, Arnold. Its looking very good.  Here is a tip for getting to the bottom screw on the strap.  Disconnect the clevis at the lever end and flip the eccentric rod over so that it is pointing the other way.  Then the bottom screw becomes the top screw.

Jerry
Title: Re: Arnold's take on the MEM Corliss
Post by: Don1966 on June 23, 2013, 10:59:25 PM
Beautifully done and well presented Arnold. Great progress a usual and she's shaping up nicely. Well done  :praise2:.

Don
Title: Re: Arnold's take on the MEM Corliss
Post by: swilliams on June 24, 2013, 06:40:57 AM
It's shaping up great Arnold. I notice you have a shot with your shoes in it, that's not one of Bob's design features is it??  :LittleDevil:

Cheers
Steve
Title: Re: Arnold's take on the MEM Corliss
Post by: Maryak on June 24, 2013, 08:42:57 AM


(http://i389.photobucket.com/albums/oo340/Maryak/Image.jpg)

That's why Arnie showed us his shoes  :lolb:

Best Regards
Bob
Title: Re: Arnold's take on the MEM Corliss
Post by: swilliams on June 24, 2013, 08:58:19 AM
 :lolb: Looks like a better present for the significant other than an B&D electric drill Bob  :Lol:

Steve
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on July 01, 2013, 06:31:39 PM
Thanks for looking in all  :praise2:

Jerry, you just made me feel very blonde  :facepalm: - of course that's the easy way  :ThumbsUp:

Steve, I didn't even notice my shoes in the shot...  It's a good thing I wasn't wearing the pair Bob suggested  :naughty: ; Just imagine the ribbing I'd have gotten from everyone over the colour of my toe-nail varnish  :Jester:

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on July 06, 2013, 08:30:51 PM
Had a couple of hours in the shop today.

First up was a a bit of 7mm brass rod turned down to 6mm with a 3mm step at the end that was threaded with a tailstock die holder:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5254.JPG)

That was cross-drilled 3mm in the mill:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5255.JPG)

Then parted off, chucked up with a 3mm collet, center drilled, and drilled 1.1mm:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5256.JPG)

A 1.4mm tap followed, officially making this the smallest hole I'd ever tapped.  The small drill chuck's shank was left _just_ free to rotate in the tailstock drill chuck, and it's surprising how little torque it took to tap the hole; just light finger-tip action:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5258.JPG)

Last week when I collected my new pair of glasses at the optician, I chatted up the lovely lass who works in the front office, and asked if it would be possible to buy out some M1.4 and M1.6 screws from them.  I soon had a packet with about 10 each in my hand, and after solemnly having to promise that I won't sell them for beer money or set up a competing shop, the price was "no charge".  I wish there was more places like this optician - not because of the freeby; that's cherry on the cake - but because they are one of a VERY few places locally that provide efficient, friendly and professional customer service; it's actually nice to go there.

Anyway, the screws I got were all 8mm long, so I had to shorten one a bit.  I tried it with the doohickey (it's not quite a true lantern chuck) that I made sometime to shorten M2 screws.  It was a bit of a loose fit, but worked:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5259.JPG)

I added about six turns of M3 thread to a length of 3mm stainless steel rod for a start on the "eccentric to disk rod", and ended up with this lot.  I forgot to take the tap out of the picture:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5261.JPG)

The 3mm stainless rod needs to have a bit of a bend in it.  I checked on the engine itself, and somewhere I must have strayed from the plans a bit; instead of the 7.5mm called for, I only needed about 4.5mm...  So I set two bits of 5mm brass flat bar (thicker than the 4.5mm to compensate for some "spring") up on the bottom of the mill vise, together with the rod - all just judged by eyeball MK1, as there is no super-precision needed for this step:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5262.JPG)

The vise was tightened up, and once released, there was a step on the rod:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5263.JPG)

I faffed around with some 2mm stainless steel rod and a 2mm tail stock die, and soon had these bits to connect the clevises of the two eccentric rods to the pivot lever:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5265.JPG)

Next up I wanted to make a start on the valves.  When checking my stock, there was not enough 6mm stainless rod, so I'll have to visit the metal-candy shop this coming week.   Things are starting to come together slowly, but there's a lot of detail left to do.  I pulled a "Jo" and started on some M3 studs to finish the shop session:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5267.JPG)
More sizing and threading needed on those....

A final overview of the engine thus far - no studs included, as those are half-screwed partially done:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5266.JPG)

So far, the parts were quite large in my experience but there's a lot of fiddly small bits coming up now....

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: Jo on July 06, 2013, 08:49:38 PM
.....  I pulled a "Jo" and started on some ....studs


Sorry Arnold I don't want to spoil your boasting but for the record you will be pleased to know that you have not (yet) pulled me  ;). The competition at the moment is rather lacking  :shrug: but concerningly hopefully after the 21st that will increase   :mischief: :lolb:

A M1.4 is equivalent to a 12BA  :whoohoo: which I know is fun there was lots and lots on my Lady S (my avatar).

Nice lantern chuck  :ThumbsUp: Small fiddly bits are fun  ;D

Jo
Title: Re: Arnold's take on the MEM Corliss
Post by: Tennessee Whiskey on July 06, 2013, 09:23:34 PM
Looking great Arnold. Nice score at the opti. You single blokes can score all the deals. Just how lovely was the lass now Arnold 8)?

Eric

Title: Arnold's take on the MEM Corliss
Post by: NickG on July 06, 2013, 09:54:57 PM
Yeah, that's why he really wants all the shops to be like that one! So didn't you let on that you were building a model engine and start explaining how the corliss mechanism works?!
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on July 06, 2013, 10:41:08 PM
Arnold, you must have switched on all your charm to get away with all those free taps.  Seriously that was a magnificent score.

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: ozzie46 on July 06, 2013, 10:51:38 PM


  That is looking beautiful Arnold. I can't hardly see that small of a screw let alone try to tap threads for one.
  Although I'm going to have to try a 0-80 or 1-72 soon for a carb. Is there a smiley for "frozen with fear"?

  Ron
Title: Re: Arnold's take on the MEM Corliss
Post by: mklotz on July 06, 2013, 11:11:22 PM
  Although I'm going to have to try a 0-80 or 1-72 soon for a carb. Is there a smiley for "frozen with fear"?

Make yourself some guided tap holders, e.g....

http://www.modelenginemaker.com/index.php/topic,274.0.html

and you'll significantly increase your chances of success.
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on July 15, 2013, 12:14:47 AM
Thanks Jo.  Pity you're so far away; you'll just have to take your chances on the 21st  :LittleDevil: .  The "Lantern" chuck works, but I need to get my finger out and build a proper kit for the different screws I use; on more than one occasion I've wished I had a better selection, and it's about time I built a decent useful set  :ThumbsUp: .  In fact, after the Corliss, there's a lot of tool-related work in my future...

Eric, Thanks.  Well, she's definitely worthy of the eye...  but unfortunately some jewelery she wore told me not to go too far  ;)

Cheers Nick - I just told her it's for building model engines; I skipped the Corliss description and rather joined in on how to spend the bit of extra cash-in-hand we all have available in Namibia after a lowering of income tax rates last month  ;)

Thanks Vince - though the score wasn't quite that big - just a handful of screws.  The taps I bought through this same optician about two years ago - albeit at a very reasonable price.  Unfortunately they can't get die nuts the same way...  And I'll bide my time; it may just be possible to get some very thin silver solder and silver solder paste through them as well - of late, I frequently pass the shop on my way to some of my clients, and once I see they're very quiet, I'll pop in and discuss that; don't want to make a nuisance of myself  :)

Ron, thank you.  Like Marv mentioned, when they get smaller you need a tap guide or tapping stand of some form.  And light fingers; the finer the threads, the lighter the touch you need.  Don't be afraid of the small sizes; I know it's daunting - four odd years ago I thought an M3 was really small; in fact I commented on that on my "first running" engine build.  Now M3 seems positively large, M2 have become a "normal" size, and less than that are just a new experience requiring some thought before-hand.  In fact, once I can get my fingers on M1 taps, I'll happily give them a go and build one of George Britnell's small engines.  The screws do get a bit small, and a pair of tweezers starts to become mandatory.  A good magnifying glass should help as well; in fact, I'm in the market for one of those myself :D


Shop time's been a bit scarce of late, but I eventually got some this afternoon.  During the week I managed to pop over to a supplier, and purchased a meter of  6mm stainless steel rod.  Somehow, the rod included two 50x50x50mm aluminium cubes from the off-cut bin as well; those just jumped into my grubby paws for some unfathomable reason ::) .

So I started off with some sections sawed from the stainless rod:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5268.JPG)

Those were faced of on one side each on the lathe.  I've not done much "multiples of the same part" work yet, but for the rest of the operations it seemed prudent that I set up some way of work-holding to make the four valves.  The tooling plate would work, so on to the mill with the tooling plate mounted in the vise.  A later photo shows more detail; this blurry one hides some of the setup, but essentially I screwed some cap-screws straight into the plate to use their heads to locate the workpieces against.  The clamp on the right-hand side screwed directly to the plate acts as a depth-stop to butt the workpieces up against.  Then I added the two clamps to hold the workpieces down - at a slight angle so that they would both hold the material down on the plate and also against the heads of the cap screws on the plate.   :-[ Confusing - I know, and also, there's a booboo waiting to happen; see if you can spot it:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5269.JPG)
Anyway, that lot worked to mill the workpieces to the correct length.

I changed the set-up slightly for the port cut-outs; you'll notice the scrap bit of aluminium I added for a better depth-stop to mill out the valve sections; things were a bit tight on the left-hand side, but OK:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5270.JPG)

On to the next machining operation.  The workpieces needed 1.5 x 1.5mm slots on the valve-train side, parallel to the cut-outs in the valves.  To set this up, I used the shank of a 3mm drill in the cut-outs to locate things.  Here you can also see one of the cap head screws I bolted down to the plate to guide things; the other is just barely visible below the clamp:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5271.JPG)

With the second clamp added, I started making the slots with my 1mm  and 0.5mm slitting saws ganged together:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5272.JPG)
If you look carefully, you might see the boo-boo happening.  It's easy in retrospect, but I didn't see things coming, except that the slots all ended up more off-center on each one, even though I'd taken good care to center things when I started...

Anyway, I slotted all the valves on both sides - slotting on either side is not on the plans, but will make setting the valve timing easier later on in the build.  I ended up with this lot:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5273.JPG)
Looks OK - only if one would consider a surface-finish in the cut-outs left by some metal-munching rodent acceptable...

And the lot in the photo above is far away from good enough...  I've alluded to the booboo, so it's time I explain the predicament to those that have not fallen off their chairs laughing yet.  The back supports of the clamps were pressing on the mill vise jaws rather than on the tooling plate itself, so, as I tightened each workpiece in turn, the tooling plate lifted out of the vise.  Have a look at the second photo in this post; the tooling plate is pretty much flush on the vise jaws, and on the last one, it's lifted nearly 0.5mm above the vise jaws...  I didn't expect that - only in retrospect does it make sense...  So I ended up with badly of-center slotted valves.  Bummer.  Lesson learned though.  Re-Do needed, and I might just pull another "Lazy Arnold" - and make the valves in one piece...

Even though the parts made today sucks, I still tried them in the engine.  Things really sucked after that - much to my surprise  :o .  This was the first time I got to try out the cylinder with sort-of valves in place.  With all the valves in a closed position, the crank-side pack nut made nice suck-blow sounds when I spun the flywheel.  And on the other end, with the palm of my hand covering the cylinder opening, there was enough suck and blow coming from the piston strokes to really feel.  And with the one of the intake valves opened a fraction, there was a very nice Shushhh Shushhh steaming-like sound.   Like mentioned; I didn't expect things to suck (or blow) that much...  The piston still needs a ring, the packing nut needs packing and so on, but for now, I'm happy.  Things may look cruddy, but she just might will end up a runner  :cartwheel:
 

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: Maryak on July 15, 2013, 02:47:36 AM
Good Going Arnold,  :NotWorthy:

Down to the nitty gritty parts now. I must admit I have everything crossed that all the angles are correct between the eccentric and the valve. (http://smileys.on-my-web.com/repository/Zen/happy-spoon-boy.gif)

Best Regards
Bob
Title: Arnold's take on the MEM Corliss
Post by: ths on July 15, 2013, 04:31:09 AM
Hi Arnold, it took me a while, but I finally saw what you meant. Bummer, but at least you know why. All in all though, good news!

Cheers, Hugh.
Title: Re: Arnold's take on the MEM Corliss
Post by: Captain Jerry on July 15, 2013, 04:51:36 AM
Arnold

Of course is will run.  It has to!  Each valve is individually adjustable!  It may take a little fiddling but that is part of the fun.  Once you get the simplified non-release version working, it is only one more step (more or less) to set up the governor controlled release trips.

It is looking very good and your almost there.

Jerry
Title: Re: Arnold's take on the MEM Corliss
Post by: b.lindsey on July 15, 2013, 12:04:49 PM
Not all bad news Arnold, bummer on the vise boo-boo, but at least you know the valves perform their function nicely which should make the re-do easier to swallow :)  Its all really coming together though very nicely!!

Bill
Title: Re: Arnold's take on the MEM Corliss
Post by: NickG on July 15, 2013, 01:11:40 PM
Looking good Arnold and sounds promising.  :ThumbsUp:
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on July 20, 2013, 07:09:52 PM
Bob, Hugh, Jerry, Bill & Nick - thanks Gents  :praise2:

Bob, thinks look on the up; today's bit gave me a good view, and though I still have to make some of those nitty-gritty parts,  things seem to pan out by eye  :ThumbsUp:

Jerry, I like your optimism in "...just one more step..."  :ROFL: - That's still quite a bit of work to do!

This afternoon I re-made the valves, and yes; I pulled the "Lazy Arnold".  On the full-size engine Corliss, the valves are made from two pieces like in the plans.  The reason for that is that the valves are actually fairly loose-fitting in the bores, and depend on steam pressure to keep them sealed to the steam ports when closed.  This also allows any water that's condensed in the cylinder to force the valve off the seat and prevents damage to the engine in cases where there's water present in the cylinder.  This does away with the need for drain cocks like found on other engines.

My model will most likely never run on steam, and even if it did, the valves are too close-fitting in their bores to allow for hydraulic lift.  So it does not really make sense to make the valves in two parts - so I proceeded to make them as single units.

I just turned the thin sections of the valves using the collet chuck on the lathe.  Next, on to the mill, and I set up things to prevent last weekend's disaster:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5274~0.JPG)

All the steps were pretty much the same, so I didn't take any photos.  I ended up with the four valves:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5275.JPG)

Installed in the engine - and out of shop time for today:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5276.JPG)

The smallest bits for this phase of the build is up next.  Hopefully I can get some shop time tomorrow and make a start on those.  So close, yet so far...

On leaving the shop, I looked up, and lo and behold; we had a crisp clear dusk with a minimum of dust in the atmosphere.  So I had a go at making the camera take a photo of something without macro mode for a change  :Lol: :
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5283.JPG) (http://www.nam-engineering.com/cm/albums/userpics/10004/IMG_5283.JPG)

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on July 20, 2013, 08:54:44 PM
What a lovely photo of the moon.  I guess yuo used a zoom lense for that shot.

Nice set of valves.  I was wondering why the plans where showing it made from two pieces.  I might do the same and do them in one piece like you did.  Did you make a slot at the back end of the valves like last time?

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: ths on July 20, 2013, 10:19:36 PM
Glad the valve issue is sorted, and a good explanation as to their full size manufacture.

Great moon shot. I think I could see my neighbour there, I believe he often visits.

Cheers, Hugh.
Title: Re: Arnold's take on the MEM Corliss
Post by: NickG on July 20, 2013, 10:59:36 PM
Amazing photo!
Title: Re: Arnold's take on the MEM Corliss
Post by: Captain Jerry on July 20, 2013, 11:00:23 PM
Arnold

Great pictures, engine and moon!  The valves look nice as well!  I don't see any advantage in making the valve and spindle in two pieces and I think that you have avoided some alignment and friction problems by making it in one piece.  Just my opinion, no evidence.

If you have not slotted the back end of the valve, I would highly recommend that you do so.  The slots should, of course, be in line with the flats on the valve and I would also recommend that you  mark the end to indicate which side of the slot is the open face of the valve.  Without some indicator it is no way to be sure of the orientation of the valves at the various phases of the cycle.

During the set up and adjustment of the valves, it is possible to leave the back covers off completely so that you can observe the orientation of all four valves simultaneously.  If the valves are a good fit in the bore and there is a good oil film on them, the air loss will be minimal or non-existant at low pressure.  The back and front covers do provide axial positioning of the valve in the valve bore but if you add a collar to the valve stem outside of the front valve cover, that will hold the valve in place.

The original published plans, without the release trip mechanism shows the valve arm held in position with a grub screw.  In my opinion, a grub screw, particularly at these dimensions, is both unreliable and likely to damage the spindle and since the position of the arm is the primary means of adjustment, a flat on the spindle cannot be used.  I would recommend that you use some kind of split clamp attachment of the arm to the spindle.  Another option would be thread the end of the shaft for a retaining nut, which would require extending the length of the spindle, or taping the end of the spindle for a retainer bolt.  In either case, the end of the spindle would need to have either a shoulder, and or a tapered land for the arm.  My preference would be a tapered land.  From experience, you will likely make numerous adjustments before you are satisfied with the performance, and I have found a tapered land to be much more reliable.

I also would advise you to first run the engine without a quick release mechanism of any kind until you are satisfied that the valve train, from the eccentric to valve edge are properly adjusted, and running smoothly.  If you then want to add the complexity of trips and governor control, you will have the confidence in the basic adjustments to deal with the added complexity.

I have not seen any instructions on how to set the valves for initial testing.  It is not difficult.  Here is how I would start out.

Give it some air!  If it doesn't start, it should at least move enough to show you which way it wants to run and you can give it a little help.

I'm not there with mine yet but I will be soon. 

Best wishes

Jerry
Title: Re: Arnold's take on the MEM Corliss
Post by: Maryak on July 21, 2013, 02:01:26 AM
Hi Guys,

Jerry and I have been exchanging ideas on release mechanisms and he is way ahead of the rest of us when it comes to the various problems encountered at such small sizes.

So yes the one piece valve is a good idea and is how they were conceived in the early days.

I  agree that a grub screw has the potential for problems, the alternative of loctite is suggested. In the case of Jerry's own design the clamping of the governor release arm is great and I will investigate this idea for the latch arm on the Reynolds Latch release.

So......................watch this space  ;D

Best Regards
Bob
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on July 21, 2013, 04:45:57 AM
Thanks Jerry and Bob. Great information.  Definetly, the valves will be made in one piece.  Just in case I come to the stage of making the trip mechanism, would the spindle need to be longer?

I was wondering how to do the initial setup for the engine. Thanks for the info.

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on July 21, 2013, 07:04:18 PM
Thanks Vince.  Yes, I added the slot at the back; it will be pretty essential for setting the timing, as it gives a visible cue of the valve's position, as well as a place to stick a screwdriver in to rotate the valve while adjusting.  No lens change on the camera for the moon shot; it's standard lens goes from 5 to 100mm giving macro to 20x optical zoom.  It also has digital zoom to 80x - that's what I used for the moon photo.

Hugh & Nick, thanks gents.

Thanks Jerry; great info!  I pretty much had the same ideas in mind for setting the timing; in fact what is there already of the valve train was set up exactly like you described.  I've already figured out which way the engine will run - currently in the wrong direction, so I need to rotate the eccentric 180o - I want it to run "over" to prevent the crank screw from unscrewing if it comes loose.
To set the valves, I was just going to disconnect them all, set the engine up exactly as you mentioned at either TCD or BDC, apply some air, and then close both inlet and exhaust valves on one side, open the inlet fully on the other side, and adjust the exhaust til it's just closed by listening to the air passing through.  Then disconnect that exhaust valve, open it, and adjust the inlet till it's just closed.  Then repeat for the other side's valves.  This should set the timing pretty well from the get-go.

Thanks Bob.  Though I didn't get to finish them today, I changed the design for the valve arms to work with a slot and small screw to set them; I seem to recall seeing full-size Corliss engines using a similar arrangement.  I'll see how that works out; it'll look slightly more bulky on the model, but should be OK...

I only had a short shop session this afternoon; some other matters needed my attention earlier on.  These bits of 3mm brass plate came from the scrap box, and was fairly close to the size needed:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5289.JPG)

These were tidied up a bit; milled to width, and one end squared up.  Then I set up the vise stop so I could drill the holes - and for the small hole tap it to 10BA in each workpiece with a minimum of fuss:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5290.JPG)

It doesn't look like it, but there's two hours of work int this lot:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5291.JPG)

Unfortunately, I only realized they're wrong once I took that last photo  :facepalm2: .  The holes are too far apart; they should have been 7.5mm apart, and I made them 12mm apart for some silly reason.  The silly reason being that I calculated the position of the 10BA hole from the end of the workpiece, but had the DRO zeroed on the 3mm hole...
Fortunately, I can salvage that in my next shop session; the mill setup is still exactly as I left it when I took the workpieces out, and there's more than enough clearance to move the 10BA hole 4.5mm closer to the 3mm hole and still have enough meat left on that side to round over the end.

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: Captain Jerry on July 21, 2013, 10:04:43 PM
To set the valves, I was just going to disconnect them all, set the engine up exactly as you mentioned at either TCD or BDC, apply some air, and then close both inlet and exhaust valves on one side, open the inlet fully on the other side, and adjust the exhaust til it's just closed by listening to the air passing through.  Then disconnect that exhaust valve, open it, and adjust the inlet till it's just closed.  Then repeat for the other side's valves.  This should set the timing pretty well from the get-go.


Arnold

Your method should work just fine for you kids with good ears.  If you have trouble hearing the air flow, as I would, here is another way that I have used.  Pipe the exhaust into a glass of water and watch the bubbles.  You can be very precise.

Jerry
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on July 27, 2013, 06:21:21 PM
Thanks Jerry.  I forget I'm still blessed with good hearing, and your idea of using the exhaust through water is a brilliant solution for those that can't hear well any more  :NotWorthy:

As always, making small bits can take just as much - if not more - time than making bigger parts.  I only managed to finish the valve arms in today's session.

First, I fixed up the booboo I made last weekend - drilled and tapped new holes in the workpieces at the correct center distance:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5296.JPG)

Then I had to think a bit about the next machining operations.  There was some fairly fine work to come; drilling holes at 1.1mm to tap M1.4, and adding 1.4mm clearance sections, with a 0.5mm slit in between the sections.  So, the issue was: slit first and then drill and tap or drill and tap first then slit.  The first option was the most convenient, but ran the risk of having some flex added to the drilling operations.  All of my small drills are basically brand new and sharp, so that mitigated the possible flexing a bit.

Off I went, and added a 0.5mm slit to each workpiece:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5297.JPG)

Then, using the vise stop again so I could finish the same set of operations that follows on each part, I first drilled it 1.1mm (tapping size for M1.4):
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5298.JPG)

To add the screw clearance, I used a sliver of drinks can inserted into the slit and drilled the 1.4mm clearance - once the sliver moved, the hole was through into the slit:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5300.JPG)

The M1.4 tap followed:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5301.JPG)
The brass I used here comes from a strip of 3mm plate I got "somewhere", and unlike most brass, it is tough and gummy to machine and tap.  Where most brasses would machine and tap with tiny bits of swarf coming off, this lot leaves long strings when drilling it, and a lot of burrs - much like soft aluminium, but kind of tougher.  This nearly bit me while tapping it; on a couple of occasions the swarf would make the tap want to seize up, and I had to to-and-fro carefully quite often to try and break up the chips that caused this. In the end, things turned out well though.

To accommodate the screw head, I milled a pocket for it.  A true counter bore would have been nicer, but at 2.6mm diameter for the screw head, I had no easy way to do that, and I was in no mood to try and make up a counter bore from silver steel for a hole this small:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5302.JPG)

Those steps were then repeated for the other three workpieces.  After trimming off the excess length of each workpiece wit a junior hacksaw, I set about tidying them up a bit, using a drill bit and a long 10BA bolt to set the side angles:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5304.JPG)
For rounding over the ends, I just kept the same height setting on the mill, and milled facets using the 10BA bolt as pivot pin.

Next followed a couple of licks with a small file, some M1.4 screws, and I ended up with this lot:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5305.JPG)

I was concerned that adding the short section for the screw might be a bit clunky, but it looks OK installed in place on the engine for now:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5306.JPG)
Rounding the ends over around the axis of the screws, and replicating the pocket on the other side will most likely look even better, but I'll leave this as-is for now.

Kind regards, Arnold

Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on July 27, 2013, 06:46:21 PM
Good progress Arnold.  I am so not looking forward to do those small fiddly bits.

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: Don1966 on July 27, 2013, 07:27:14 PM
She's looking good Arnold, still following along here. Looks like you are not far from completing it. Don't those small parts take up a lot of time?

Don
Title: Re: Arnold's take on the MEM Corliss
Post by: Marinus on July 27, 2013, 09:42:38 PM
Looking good Arnold. I like seeing skillfull model engineers making small parts.
Title: Re: Arnold's take on the MEM Corliss
Post by: b.lindsey on July 28, 2013, 01:11:01 AM
Just amazing stuff Arnold. Those assembly shots are most inspiring!!!

Bill
Title: Re: Arnold's take on the MEM Corliss
Post by: ProdEng on July 28, 2013, 02:19:35 AM
The valve arms look great Arnold.  M1.4 is a very small screw, more like clock making  ;)
Title: Re: Arnold's take on the MEM Corliss
Post by: steamer on July 28, 2013, 12:48:10 PM
That's really coming along beautifully Arnold!.....I like it! :ThumbsUp:

Dave
Title: Re: Arnold's take on the MEM Corliss
Post by: Tennessee Whiskey on July 28, 2013, 01:26:34 PM
Arnold, nice job. I kinda like the screw ends as they are. In the photo I see nice straight lines around the outside and roundness in the center part. They just look like they fit the design. Just my 2 cents, hadn't checked the exchange rate let me know if I owe you any extra :cheers:

Eric
Title: Re: Arnold's take on the MEM Corliss
Post by: Bearcar1 on July 28, 2013, 06:48:28 PM
Looking good Arnold. I like seeing skillfull model engineers making small parts.


I'll second those sentiments ......  :ThumbsUp:


BC1
Jim
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on July 29, 2013, 12:28:09 AM
Thanks very much for looking in All  :praise2:

Vince, the small bits aren't all that bad; it just takes a bit more planning to do the machining - especially for work-holding.  Oh, and not dropping them; that's instant shop-monster food.  Actually I'm enjoying making the small bits; except for the smaller threads, these are of a similar size to quite a few parts I've made for the various versions of Elmer's engines I've built - though Elmer had a knack for simplifying the small parts a bit.

Don, yes; they do take time - as today's progress might show!

Marinus & Jim, thank you; that's high praise, but I don't consider myself a skillful model engineer.  I'm still learning every step of the way, and in this build there are a lot of "firsts" for me.

Jan, yes, the screws are small - and some horological tools would be a boon.  In fact, my list of "tools-to-make" still keeps on growing, and a lot of it especially for smaller parts.  After this engine is completed, I'll spend quite a bit of time doing some tool-making jobs.

Eric, your 2 cents run through the exchange rate is worth a whopping 19 Namibian cents today, so I'll gladly take it  ;)

On to some more small bits.  The disk arms are the smallest parts on the engine, and I'd been puzzling over how to make them.  If I made them from three separate pieces each like on the plans, I'd have to single-point thread the spindles either M1.4 or M1.6 as I don't have dies for those sizes.  That would have been a nice challenge; I'm one of the few people around who actually likes screw-cutting on the lathe, and even though these are very fine threads, I'm pretty certain I can do them with a razor-sharp honed toolbit.  What I couldn't figure out was how to make the eight arm ends with the tooling I have...

"Arnold" is derived from "Eagle" - so it's with great trepidation that I sully my majestic avian namesake with what's to follow...

I turned "lazy" mode on, and decided to make the disk arms as single pieces.  There were still some machining issues to overcome, but a plan was hatched and off I went.

Things started off with short sections of 5mm hex brass rod - much longer than needed, as I needed a way to hold things later on:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5307.JPG)

I turned a 2mm pip about 4mm long at one end of each of the pieces.  My Myford's 3-jaw chuck is pretty badly off center at this size, so I marked the flat that lied between the #1 and #2 jaws so that I could later on chuck up the workpieces again and keep the best possible centering on the pip I turned.  Then it was off to the milling machine with the tooling plate mounted in the vise, and I set things up so I could repeatably drill the workpieces with the 14.7mm distance between the holes.  A bit of scrap aluminium plate served to both lift the workpieces a bit so the clamps didn't foul on the cap screws at the back and prevent proper clamping, as well as prevent drilling into the tooling plate:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5308.JPG)

After drilling the holes, I switched to an 8mm cutter and set it to height to mill off 1.25mm.  Things were a bit tight between the clamping spaces on the tooling plate, but it worked:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5309.JPG)
As always, between milling each side of the workpieces, I followed that golden rule that Mr Philip Duclos mentions so often in his writings.  Clean away the chips and de-burr the workpiece.

With the milling done, I ended up with this lot:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5311.JPG)
As you can see, there's the 2mm spigots I turned on each workpiece, and on the left, on the faces facing the camera, the permanent marker markings I mentioned earlier that corresponds to the opening between the #1 and #2 jaws of the Myford's three jaw chuck.  Also, the metal-munching rat left it's hallmarks in the middle of the cut-outs; I didn't worry about that.  Boring really, but there's a little method to this madness...

Back to the lathe with the workpieces, and a type of set-up I'd never used before.  All the boo-hah about the 2mm pip at the end of the stock and marking the place to re-mount in the chuck now came into play.  I wanted to turn down a section between the holes drilled into the workpieces to 1.5mm.  I could have used my small revolving center for support at the tailstock side, but that puts an axial load on the end of the workpiece, and when things get this small, it could just buckle it up.  So a bit of 2mm inner diameter tube chucked up in the the small drill chuck in the end of the big tailstock drill chuck, with a drop of oil added would provide a running center without adding axial tension to the workpieces.  After digging around all my HSS cutting tools, I selected a suitable toolbit; this one was originally shaped to cut the worm gear from back when I made my rotary table:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5312.JPG)

With a drop of oil on the spigot at the end I shoved it into the bit of tube in the tailstock chuck.  Some turning followed.  Very carefully.  The joys of turning brass with a nice sharp toolbit with zero rake manifested itself; with 10 thou initial and later 5 thou in-feeds as things got smaller, everything turned out well.  The shaft of the workpiece is 1.5mm, and the steps up from that is 2mm:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5313.JPG)
 :-[ I have to say, most of the turning was just eyeballed - I just used the same settings on the cross-slide for in-feed for all the bits, but no measurement for the shoulders or the distances to the holes.

The bits were just hacked off the parent stock with a junior hacksaw, and then I started cleaning them up on the mill and with files.  All too soon, shop time ran out, but I managed to mostly finish off one bit after a lot of loving care with a needle file after rounding it over on the mill.  One done, one partly done, and the rest to go...  Well, that's some progress of sorts anyway:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5315.JPG)

The small bits can be a bit tricky, but it's a lot of fun.  I'm really enjoying this  :whoohoo:

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on July 29, 2013, 07:15:01 AM
Nice one Arnold.  You are making my life easy. :ThumbsUp:

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: ProdEng on July 29, 2013, 11:51:52 AM
The arms came out very well and I love the methods.  Using hex stock with the flats for reference surfaces is a gem along with the bush in the tailstock for workpiece support.
Title: Re: Arnold's take on the MEM Corliss
Post by: Jo on July 29, 2013, 12:05:53 PM
The small bits can be a bit tricky, but it's a lot of fun.  I'm really enjoying this  :whoohoo:

 8)

I agree, I always find that it is the tricky bits that (can) give so much satisfaction and pleasure .

Jo
Title: Re: Arnold's take on the MEM Corliss
Post by: b.lindsey on July 29, 2013, 12:33:16 PM

The small bits can be a bit tricky, but it's a lot of fun.  I'm really enjoying this  :whoohoo:



And we are enjoying watching Arnold !!!  Lovely work as usual.

Bill
Title: Re: Arnold's take on the MEM Corliss
Post by: spuddevans on August 05, 2013, 03:48:23 PM
This is coming on really well, looking really good Arnold. Keep up the good work.


Tim
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on August 11, 2013, 04:05:07 PM
Vince, Jo, Bill & Tim, thanks for checking in!

Things were very quiet in the shop of late; there was this little matter of a week-long business trip I had to take to South Africa and all the preparations that went with it...

Yesterday I finally made it back into the shop for the first time in two weeks, and finished off the spindle arms:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5316.JPG)

All the threads I used for mounting the spindle arms to the valve disk and valve arms are 10BA (which is as close as can be to 1.6mm), but the holes in the spindle arms I made 2mm, as I prefer to use shoulder bolts in this type of application.  This is not on the plans; it is merely my own personal preference.  As these bolts are fairly small, I didn't want to make the bolts from brass, and rummaging through my stock I found I had silver steel and stainless steel of a suitable size.  I went for the stainless purely because it won't rust.
After grinding up and finely honing a new toolbit from a HSS blank, I started turning up the bolts - jotting down the cross-slide readings once the first one was on size to make it easier to make the rest.  Lazy as always, I used the grooves in the collet closer nut to index by eyeball where I needed to file the flats to make the hex head, and just counted file strokes to get the flats all to the same size.  Here's the first one basically finished:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5318.JPG)

I just used a junior hacksaw to separate the bolts from the parent stock, and afterwards chucked them up in the small ER11 collet chuck to face the heads to equal thicknesses.  After a while, I had the 8 bolts needed; I actually made ten, but the shop monster was really hungry and ate two of them...:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5321.JPG)

Then I assembled things on the engine:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5323.JPG)

While assembling things, it occurred to me that the engine was now at a point where it might just run, even though it's not mounted and still missing some bits like the valve covers and so on.  Quick as a flash I turned up an impromptu air connector (already visible in the photo above, and set all the valves to "just closed" by turning the engine to top dead center and adjusting the valves so their slots showed the were in a definite "just closed" position (that's why they're slightly angled):
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5322.JPG)

Well ? - does it work ?




YES!  :whoohoo:
Even though the piston still needs a ring, and nothing is bolted to the base (the screws you see are just dropped in to locate things but not bolted up), and there's not a gasket in sight, it runs, and surprisingly well at that:
http://www.youtube.com/watch?v=7Xlw7IaVVsY

The valve covers still needs to be made, as well as the proper steam valve, and then it needs lots of studs and painting, so it's about 50% done.

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: Jo on August 11, 2013, 04:28:40 PM
Well done Arnold  :praise2: now why can't I get mine to do that  :lolb:

Enjoy the studs.  ;D

Jo
Title: Re: Arnold's take on the MEM Corliss
Post by: Jasonb on August 11, 2013, 04:34:59 PM
Well done on a nice engine, just the beutyfiying to do now.

J

PS keep it on the slow speed :)
Title: Re: Arnold's take on the MEM Corliss
Post by: Don1966 on August 11, 2013, 04:46:35 PM
Awesome Arnold, that is one beautiful running engine, it sure runs good at slow speed. I like..........  :praise2:

Don
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on August 11, 2013, 04:58:25 PM
Yippee it works.  Nice one Arnold.   :praise2: :praise2: :praise2:

Well it gave me a deserved kick in the backside to get on with mine.

Just a silly comment if you don't mind.  Why don't you put the linkages on the front side of the wrist plate.  They might look nicer.

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: Stilldrillin on August 11, 2013, 05:53:27 PM
Well done Arnold!  (http://freesmileyface.net/smiley/respect/respect-044.gif) (http://freesmileyface.net)   (http://freesmileyface.net/smiley/respect/respect-044.gif) (http://freesmileyface.net)

A great runner, "straight out of the box".  :praise2:

And, finishing off, will improve it further!  :whoohoo:

Very pleased for you......  :ThumbsUp:

David D

Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on August 11, 2013, 06:01:32 PM
Jo, Jason, Don, Vince& David, Thanks !

Quote
Enjoy the studs.  (http://www.modelenginemaker.com/Smileys/default/grin.gif)

 :Lol: - I'll try.  Need to make some holding bits first, and set up the mini lathe properly; it's been languishing for two years and never really did anything, and it's about time the ML7 had a bit of a rest...

Quote
PS keep it on the slow speed :)
Aye - definitely.  Once she's fully done, I'd like to run her as slow as possible - no use in missing out all the interesting action in a blur of motion!

Vince, not a silly comment  :)  This is per the plans - you can check here (http://www.modelenginemaker.com/index.php/topic,1285.msg17846.html#msg17846).  You could change it over to run on the front, but then you'd need to make some changes first. 
As it is currently, the bolts on the top two linkages would foul on the valve rod, and the mounting section of the valves are a tad short.
So if you'd have to make the "eccentric rod to valve disk swivel" longer to add some room to add the clearance for the valve arms.  And then there's a choice to overcome the "too short" mounting ends of the valves; the easiest would be to make the valve disk hub about 3-5mm shorter and adjust the spindle dimensions accordingly - with this way all the other measurements and dimensions stay the same.  If you don't change the disk hub dimensions, you'd have to make the turned-down section on the valves about 3mm longer, as well as bend the "eccentric to disk rod" a bit more to compensate.
Sounds like a lot to say, but it's not difficult once you choose the way you'd like.  If you want to add the governor, you might have to be a bit more careful; I didn't check how the changes would affect that.

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: Bearcar1 on August 11, 2013, 07:29:40 PM
Greetings Arnold, and as usual, I'm late for the party.Ya **just** couldn't wait until you were finished before you put the air to it could ya?  :lolb:  I couldn't either. What a splendid thing to behold! Some tweaking here and there yet to do but still, it is so majestic in stature. Nice and slow. It's a beauty for certain. You are planning on building the governor? Yes, No? Maybe? Well done and thank you for sharing the ride with us.  :ThumbsUp:


BC1
Jim
Title: Re: Arnold's take on the MEM Corliss
Post by: Tennessee Whiskey on August 11, 2013, 08:07:44 PM
There has got to be something to this "Lazy Way" of doing things as that is just absolutely, positively, stinking awesome. I'm speechless and that very rarely happens to me.

Whiskey
Title: Re: Arnold's take on the MEM Corliss
Post by: tel on August 11, 2013, 10:40:05 PM
GEEZ! I missed a couple of episodes and now it's running! Well done Arnold! :ThumbsUp:
Title: Re: Arnold's take on the MEM Corliss
Post by: pgp001 on August 11, 2013, 11:19:37 PM
Arnold

Lovely job, it must be very satisfying that it runs so well first time.

Just one question, is it designed to run in that direction ?
My Pollit & Wigzell runs the opposite way, the theory being that the crosshead thrust will be downwards onto the slides which are machined into the bedplate. I suppose with a trunk guide it makes no odds which way it runs.

Phil
Title: Re: Arnold's take on the MEM Corliss
Post by: Maryak on August 12, 2013, 12:17:54 AM

Even though the piston still needs a ring, and nothing is bolted to the base (the screws you see are just dropped in to locate things but not bolted up), and there's not a gasket in sight, it runs, and surprisingly well at that:



And that my friend is proof positive of your skill as a model engineer.

I cannot say how much it means to see the successful fruit of our labours in the flesh.

Congratulations.

Best Regards
Bob
Title: Re: Arnold's take on the MEM Corliss
Post by: ths on August 12, 2013, 12:25:32 AM
Just saw the vid Arnold, you must be on top of the world. Well done, and to the designers as well.

Cheers, Hugh.
Title: Re: Arnold's take on the MEM Corliss
Post by: ozzie46 on August 12, 2013, 12:51:22 AM


   Hooraaaayy!! It runs.  The fact that it runs without gaskets and the other stuff is testiment to your skill and the viability of the design. Thanks to all who worked on developing it and to you for taking us a long for the ride.   :praise2: :praise2: :praise2:

   Ron
Title: Re: Arnold's take on the MEM Corliss
Post by: Captain Jerry on August 12, 2013, 01:46:06 AM
Of course it runs!  It is meant to!  That's the way it was designed!  The only thing that would keep it from running is sloppy work and there is no evidence of that here.  Just good, careful, step by step progress to an inevitable conclusion.  Still, it is magical, majestic, and cool as it can be.  Makes you want to just sit and grin, don't it!  Oops! I went redneck there for a minute. Hope you don't mind.

I could have just said "Nice work" but these things really deserve a celebration so, here  :whoohoo: :whoohoo: :whoohoo:
Three cheers.

Jerry
Title: Re: Arnold's take on the MEM Corliss
Post by: sbwhart on August 12, 2013, 06:23:30 AM
Way to go Arnold  :cartwheel: :cartwheel: :cartwheel: :cartwheel: :cartwheel:

What a great running engine ticks over real slow and that linkage looks like a spider doing the tango   :ROFL:

I've followed along quietly and a must say what an interesting project  :ThumbsUp:

Stew
Title: Re: Arnold's take on the MEM Corliss
Post by: NickG on August 12, 2013, 10:48:54 AM
Looks great and runs just as well - well done Arnold and to those who designed her.

Nick
Title: Re: Arnold's take on the MEM Corliss
Post by: ProdEng on August 12, 2013, 11:00:39 AM
Looks and sounds fantastic at low speed, well done Arnold  :whoohoo:
Title: Re: Arnold's take on the MEM Corliss
Post by: b.lindsey on August 12, 2013, 11:57:48 AM
Simply excellent in every respect Arnold.  The fact that is runs so well even now, should make the finishing work all the more satisfying. I'll be following along until the very end!!

Bill
Title: Re: Arnold's take on the MEM Corliss
Post by: gbritnell on August 12, 2013, 12:00:04 PM
Outstanding work on the Corliss. I really enjoy watching the valves working. When it's painted up it will be quite an impressive model.
gbritnell
Title: Re: Arnold's take on the MEM Corliss
Post by: swilliams on August 12, 2013, 01:53:45 PM
Fantastic Arnold, she's going to come up a treat with all the finishing touches and already runs great.

Congrats
Steve
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on August 12, 2013, 07:00:44 PM
Thank you all for your kind replies  :praise2:

Bob:
Quote
And that my friend is proof positive of your skill as a model engineer.
Bob, thank you, but I don't consider myself skilled.  There has been a lot of learning during this build, with more to come. 

Quote
I cannot say how much it means to see the successful fruit of our labours in the flesh.
Me too - Thank you and the rest of the team  :praise2: - the least I could do to contribute beyond yapping about metric sizes and complaining about small screws was to at least build it to prove that all the design work was worthwhile, and it really is.  I used all the essential dimensions as-is, and that is now proven to work well, so anybody else building the engine can rest assured that all the core dimensions are correct to build a running engine.  As Jerry mentioned, that's what it was designed to do, so here's three cheers to the design team  :cheers: :cheers: :cheers:. 

Jim, yes, I'll definitely give the governor a go; I first want to get the engine looking a bit better though - there's some bits that need re-making and all the paint work, and I do need a small break to sort out the shop a bit as well... 

Eric, a speechless redneck ???? - I've never seen (or heard) that...  Some moonshine will cure it double-quick - just make sure there's no FDA's about  ;)

Phil, yes; it is extremely satisfying.  At a quick count, this is my twentieth engine, and the thrill of seeing an engine's first run never diminishes. 
The MEM Corliss can run in either direction simply by rotating the eccentric through 180o.  In fact, at final assembly, I'll make this one run the other way - simply because with the rotation as-is currently it will be inclined to loosen the crank screw over time, especially if there's a little friction there.  In fact, it will be very easy for other builders to make a slip-eccentric to make it run either way  ;)

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on August 12, 2013, 10:02:38 PM
Well Arnold you made my day yesterday when I saw your Corliss actually running.  It gave me a gaol to aim to. I am still way behind you in my build but slowly I will get there.

Vince

ps. What is a slip eccentric?
Title: Re: Arnold's take on the MEM Corliss
Post by: Maryak on August 13, 2013, 01:12:06 AM
Hi Vince,

The attached PDF explains slip or loose eccentric better than I could.

Hope it helps.

Best Regards
Bob
Title: Re: Arnold's take on the MEM Corliss
Post by: ReFlad on August 18, 2013, 03:33:33 AM
Effen awesome Arnold!  I am not surprised that it runs so well without all of its parts.  It shows what type of craftmanship built it.  Great build.  Great Engine.  Very enjoyable!

Ronald
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on August 21, 2013, 05:21:03 PM
Thanks Vince, Bob & Ronald - my apologies for the late reply.

I've had a couple of enquiries regarding the mention of a slip-eccentric.  In addition to Bob's picture, I'll do a little write-up in another post on one I've made; it might be useful to see photos and a short video of it working.

There's been zero progress on the engine, and most likely I'll only get to work on it in about a week and a half's time again.  From here, updates will be a bit slower.

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on October 13, 2013, 12:18:13 PM
Well, the week and a half turned into more than a month and a half...

Yesterday I took some time from a very hectic schedule, and messed up the shop a bit.

I never got around to making the valve bonnets, so I started off with strips of 1.2mm brass plate for the rear valve bonnets.  The plans call for 1.5mm, but I don't have any.  As the insides of the plates will be subject to air/steam pressure, these cover plates can not be too thin, but 1.2mm over the 15mmx15mm area is well within safety limits for a working pressure of 60psi:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5390.JPG)

One strip was squared up and brought to 15mm width, then I started to drill holes in it.  The first holes was a booboo - I drilled them 0.5mm too close to the end...:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5392.JPG)

So I used the second row of holes as a new starting point, and drilled all the holes for the covers, leaving enough space in between each set of four to saw off the covers:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5393.JPG)

Once sawed apart, I just used two drills through the holes to clamp the lot together to mill the sawed sides to size:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5394.JPG)

The plates were still a bit rough-looking:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5395.JPG)

That was easily taken care of with a quick flat-rub on some 600 emery:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5397.JPG)

On to the front valve bonnets.  I've been looking around for some 15 or 16mm square brass bar, but have been unable to find any.  I have about 300mm of 25mm square brass, but making them from that would be a bit too wasteful at the going rate of brass.  What I did have floating around was an 8mm thick slice of 50mm square bar end:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5398.JPG)

After a quick head-scratch as to how I could make that into the bonnets, I settled on a plan of attack.  First was to bring a suitable section of it down to 6mm thick:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5399.JPG)
It wasn't clamped on by much, so I took things easy with many light cuts.

The thinned section was sawed into two strips; those were then milled to the needed 15mm width.  I then set up the vise back-stop, located the end of the workpiece, and from there the center of what would become the first bonnet.  Then I drilled all the holes.  Scratching around my stock of O-rings, I found the thinnest 3mm ID ones - they have a 1.5mm thickness - so I used a 6mm slot mill to counter-bore 1.4mm deep:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5401.JPG)

The rest were easy to do; rotate the part 180o to make the other one - using the stop to locate it, and repeat for the other strip.Then saw them apart:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5402.JPG)

And clean up the sawed edges - once again using drills to determine the height for quick workpiece rotation:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5403.JPG)

To turn the spigots, I just faced a bit of aluminium scrap in the lathe, and with a bit of cardboard set things up for friction drive in the lathe:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5404.JPG)

Turned down - with light cuts and a sharp tool so as to prevent jam-ups:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5405.JPG)

The others followed, and I ended up with this lot for the shop session:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5406.JPG)

Somehow a small cup-fed HVLP spray gun followed me home a while ago.  I guess it's time I started to "play" with it...

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: steamer on October 13, 2013, 01:38:45 PM
Nice job on the bonnets Arnold.   

Dave
Title: Re: Arnold's take on the MEM Corliss
Post by: Don1966 on October 13, 2013, 04:46:26 PM
Nice job on the bonnets Arnold.   

Dave
What Dave said, I like your technique.

Don
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on October 13, 2013, 04:50:51 PM
Good job on the covers Arnold.  I'm still stuck with the cylinder feet.

I see you are using an O ring in the front covers as per plans.  If I use a gasket instead of the O ring do you think I can get away with it?

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: Maryak on October 13, 2013, 10:36:00 PM
Hi Vince,

Th O ring is to seal the valve shaft. I'm not sure a gasket will do that.

Best Regards
Bob
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on October 13, 2013, 10:58:51 PM
Thanks Bob.

In that case a gasket will not do.

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: Captain Jerry on October 14, 2013, 04:02:36 AM
Arnold

That is a nice looking set of bonnets.  In my experience, this is a critical step as it affects the free rotation of the valve.  You have allowed for a .1mm compression of the O-ring but I am not certain how the seal functions in this design but it seems that as the front and rear bonnet are tightened, the O-ring is compressed between the shoulder of the valve and the bottom of the bore in the bonnet, sealing on the face of the shoulder as well as sealing against the reduced shaft diameter as the ID of the O-ring is reduced by compression.

There are a number of critical dimensions that have to match up, including the thickness of the cylinder block, the length of the valve body, the depth of the bonnet bore, the thickness of the O-ring, and the thickness of any paper gaskets between the bonnets and the cylinder block. If there is too much compression of the O-ring, the amount of force needed to rotate the valve can be excessive.  You can create the same problem by over tightening a piston rod  or a valve rod gland, but that is easily overcome by the force of the piston or the eccentric linkage but it reduces the efficiency and performance of the engine.  A little extra friction on the exhaust valves of a Corliss engine is also overcome by the eccentric linkage.

The steam valves are a much bigger problem if you intend to include the trips.  When the release trips, the valve is disconnected from the eccentric and the only force acting to rotate the valve is the dash pot.  Not much force at all.  You can increase the weight of the dash pot or the spring but that makes the release point less reliable.  It is a two edged sword.   If the dash pot can't rotate the valve, you don't have a working Corliss valve.  If the release doesn't trip reliably, you don't have a working valve either.

In addition to the seal friction, the bonnet bore must be concentric with the valve bore and since there is no spigot for registration, that leaves the four bolts to control the position.  The cheap digital scales on my mill are certainly not perfect and getting the four holes of the bonnet to register perfectly with four holes on the cylinder block is a challenge that usually requires over sized clearance holes in the bonnet.  I have had valves that turn freely, lock up solid as the last bolt is tightened.

I hope you don't mind me pointing out the difficulties that you are facing.  You are probably already aware of them and I am sure that you can deal with them and produce a working engine, but most viewers may not be aware of them and therefore not able to appreciate the challenge you are facing.

Get your fiddle tuned.  You're in for some fine fiddling.

Jerry
Title: Re: Arnold's take on the MEM Corliss
Post by: swilliams on October 14, 2013, 07:50:58 AM
Good stuff Arnold, nice to see you back at it  :DrinkPint:

Steve
Title: Re: Arnold's take on the MEM Corliss
Post by: NickG on October 14, 2013, 07:55:43 PM
Yes nice work Arnold, still watching.
Title: Re: Arnold's take on the MEM Corliss
Post by: ReFlad on October 18, 2013, 03:03:22 AM
You haven't lost your talent Arnold.  Nice work!
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on October 19, 2013, 11:36:24 PM
Thanks All  :)

Jerry raises a couple of very important points, especially the ones about friction.  For all intents and purposes, I don't need the O-rings; in fact, I initially planned to go without them.  From the first run of the engine, it was quite clear that there was very little blow-by past the valves, and the use of a thick lubricating oil on them will help reduce that to practically zero.
If the O-rings give me problems, I'll replace them with PTFE tape - that's what I'm using on the piston rod gland.  Graphite string would be better, but that's unobtainium in Namibia; I'll get some from overseas at some point.  The advantage of the tape/string is that one can add or take away bits to make things work better.

Anyway, for Vince and others' benefit - If you do make the valves a close but free-running fit in very smooth bores, you pretty much don't need packing of any kind for the valve bonnets, nor the

Oh, and I shudder at the thought of trying a fiddle...  I'm pretty sure it'll sound like someone trying to play the bagpipes  :Lol:

I had a job to do at a client's site this morning.  After a pretty hectic week at work, where nothing turned out to be quick or easy, I expected this one to follow suit, but, amazingly, it turned into a fairly quick and easy job.  So I had the opportunity of a bit of unexpected shop time.  With all the engine parts (except for fasteners) made, I disassembled everything - well mostly.  In keeping with trying to work a bit tidier, I salvaged an old cutlery tray from the kitchen to keep the parts together.  I kept all the bits that needs painting separate:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5407.JPG)

The one part out of place in the photo above is the valve disk...  I was trying to decide on whether to re-make it, or try and tidy up this one a bit and use it as-is.  Well, as you all know, I'm lazy and I quite like the thinner middle appearance on it, so I decided to keep it.  After some careful filing it looks a bit more presentable.  I forgot to take a photo of it, so I'll do that for the next post.

With the time that's elapsed since this build began, most of the steel parts have developed a light layer of surface rust.  Either I should have been more careful about oiling them up, or I should have painted them as I built them - at least with primer.  As I did neither, there was a bit of elbow grease required, so I started rubbing off the rust with a bit of Scotch-Brite (the fairly coarse green one sold as house-hold pot scourers locally) - to get rid of the rust, as well as to provide a key for the primer:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5408.JPG)

Next up was an impromptu spray booth.  I cobbled together a make-shift structure with odds 'n ends...  Two square tubing side-frames I had floating around (those were originally made ten years ago and were to be part of a removable bottom for Shrek's cage), some rectangular PVC trunking I had left over from installing telephone cabling in my house when I moved in, all tied together with electrical insulation tape and covered with split apart plastic refuse bags - with some old newspaper as a bottom.  Not pretty, but functional:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5409.JPG)

I mentioned in the last post that I bought a new spray gun.  It's nothing fancy; a cheap & cheerful Asian made one (cost about US$ 35), but on the surface of things, it appears acceptably made and all the adjustment screws and trigger operate fairly smoothly.  I do have another spray gun, but it has a 1l cup at the bottom, and for trying to spray models, it's much too big.  The bottom cup leaves nearly enough unusable paint left over in it when empty to just about spray a complete model.  The new gun has a 120ml cup at the top, which means its easy to mix up and use small quantities of paint.  This is the spray gun:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5413.JPG)
An airbrush may be more suited to this kind of work - I do have one that needs a bit of TLC, as all it's O-rings and so on have perished, BUT, most airbrushes only works well with thin paint.  The "filling" etch-primer I have for this project needs a more robust spray gun for the higher viscosity paint.

I spent some time masking of various bits of a selection of the parts with ordinary paper-based masking tape.  There are better products out there for masking off things, but I used what I had on hand.  Some bits were lightly pinned to blocks of wood with brads through mounting holes to keep them in place.  The bearing pedestal was just shoved on a bit of bent brazing wire to make a "handle" for it while painting; the handle to be used to hang on a hook to dry.  The cylinder cover was literally just stuck to the wooden block with more masking tape.  For the two bearing blocks, I just used an 8mm bolt in each with masking tape wrapped tightly around to keep them in place and to protect the edges of the bronze bushes from paint.  All of this was just that there was some way to handle the bits while painting to get at all sides, and also to safely store it for drying:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5410.JPG)
None of the pieces shown have any holes with threads in them, so I didn't bother to plug the holes.  It will be easy enough later on to clean paint from the holes with a drill bit...

After a last wipe-down with bits of my plentiful "John Wayne"(*) shop toilet paper lightly soaked in thinners, on to a bit of paint.  And all of this was VERY new to me...  Seeing as the spray gun was new, I ran about half a cup full of clean thinners through it spraying at a bit of cardboard.  I tested the different controls on the spray gun to test what they were used for and how they responded.  The clean thinners was just to make sure the gun was thoroughly clean before I tried paint.
Eventually I mixed some of the primer with thinners according to the instructions in a separate clean empty jam bottle.  The instructions said 30% - 40% thinners to paint; I opted for the more viscous option because of the relatively small spray gun and went for 40%.  A quick test on a bit of scrap plate, and with some fiddling with the controls I got a passable result, so I went ahead and sprayed all the bits.

I've used rattle-cans to varying degrees of success in the past; in fact, most of the painting I've done on models thus far have been done with rattle-cans (with some free-hand brush painting making up the rest).  In all cases, tying to get a nice and even coat of primer on them proved to be very difficult, with quite a bit of work needed afterwards to smooth things with wet & dry, or in many cases a complete strip of all the paint for a retry.  I found applying the paint with the spray gun was much easier.  It gives greater control, and things turned out pretty well.  As I finished each lot I stuck them in the old oven Don mentioned in my shop revamp to dry off:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5411.JPG)
No heat or anything; it's just a nice and dust-free place to store them.

This paint dries pretty quickly; on my test plate it took just 15 minutes to be completely touch-dry - it was a nice warm day today at about 32oC with a smidge of humidity.  So after about an hour I took the bits out of the "oven" for some photos.
I've mentioned before that I don't like painting things, but it's one of those things that needs to be done.  Most of Elmer's engines looks great without any paint, but some colour does add character.  On a bigger model like this it's part and parcel of the build.

Please pardon my enthusiasm...

   :whoohoo: :cartwheel: :whoohoo:

Of all the primer paint jobs I've tried so far on engines, this was by far the easiest, with the most satisfactory results straight-away.
It easily covered in one thin coat, but did not tend to draw away from any sharp edges like I've always had.  And the "filling" part of this primer also looks to be doing well; it covered toolmarks and went into corners very well and pretty evenly:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5415.JPG)
And
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5416.JPG)

That was the shop session for the day - and quite satisfying at that  :)

Kind regards, Arnold

(*) "John Wayne" shop toilet paper: It's rough and tough and takes crap from no-one.  Non-perforated industrial toilet paper supplied on big rolls.  Doesn't tear or fray easily. 
Title: Re: Arnold's take on the MEM Corliss
Post by: Tennessee Whiskey on October 20, 2013, 12:17:56 AM
Well Pilgram, pretty darn good looking painting ya did there. Nice one on the paint booth. Put a small A/C filter on one wall, cut a hole, and put a fan on the outside, exhausting the over spray out. Getting rid of the over spray makes a much nicer topcoat. Old window box fans work great. Can't wait to see it back together.

Whiskey
Title: Re: Arnold's take on the MEM Corliss
Post by: swilliams on October 20, 2013, 12:53:48 AM
Very nice Arnold

I want to learn more about this painting business. If you got good at it it could even be fun  :o

Steve
Title: Re: Arnold's take on the MEM Corliss
Post by: Dave Otto on October 20, 2013, 12:59:09 AM
Nice looking parts Arnold!



Dave
Title: Re: Arnold's take on the MEM Corliss
Post by: Don1966 on October 20, 2013, 01:44:10 AM
Arnold love the piaint job, I need to get me a spray gun as I have never tried it. Glad to see you making use of the oven, it will be handy in cold and rainy weather to bake your engines with. I usually leave mine at 200 degree F. Good to see that your getting close to finishing bud. Awaiting the final paint job.

Don
Title: Re: Arnold's take on the MEM Corliss
Post by: Maryak on October 20, 2013, 02:06:53 AM
Almost there :cartwheel:

Love the bonnets and your nice clean oven...............lots of scrubbing or very little cooking?  :LittleDevil:

Best Regards
Bob
Title: Re: Arnold's take on the MEM Corliss
Post by: Steam Haulage on October 20, 2013, 09:54:48 AM
Just for the record,
The primer you used is 'technically' known as a primer-surfacer. A long time ago a primer was applied and allowed to dry/cure and then a separate coat of surfacer applied and dried/cured. Eventually some bright spark(s) combined the properties into one product. The surfacer contains a high loading of extenders, such as barytes, china clay etc which provides build over the metal and after sanding a good surface for following coats.

JerryNotts
Title: Re: Arnold's take on the MEM Corliss
Post by: Steamer5 on October 20, 2013, 09:58:14 AM
Hi Arnold,
 Loving this build.
Just an idea for your shaft seals... the old guys, no longer with us, from my club commented several times about using PTFE tape for shaft sealing that it wasn't a good idea as galled (think that's the spelling) the shaft, they were talking about piston rods though, rotating shafts may be OK.
If you are going hunting for graphite string try hunting down graphfoil tape.....this stuff looks to be straight graphite, corrugated of different widths. Easy to cut to width, wind on enough to slide into packing recess & tighten gland, it will then deform to what ever shape required & gives a nice slippy surface. Got some at home & can proved a bit more info from the label if anybody is interested

Cheers Kerrin
Title: Re: Arnold's take on the MEM Corliss
Post by: ozzie46 on October 20, 2013, 01:37:07 PM
  Coming along nicely Arnold.   :ThumbsUp: :ThumbsUp: :ThumbsUp:

  Ron
Title: Re: Arnold's take on the MEM Corliss
Post by: Captain Jerry on October 20, 2013, 01:52:57 PM
Yippee!  I found a package of graphite yarn at a local hardware store!  This stuff is hard to find these days.

Phooey!  Don't believe the label.  Even though it is called "Graphite Yarn" on the label, it contained no graphite and no yarn.  It looks like yarn, three strand twist but it is not. The first clue was that it is very clean, no dirty black smudge.  It turns out to be three strands of twisted black, glossy, PTFE or something like it.  Each strand can be untwisted to reveal a flat tape.  Rats! 

Jerry

PS found at True Value Hardware with True Value label.
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on October 26, 2013, 05:46:39 PM
Thanks All  :praise2:

Steve, you might want to have a look at Christopher Vine's book "How (not) to paint a locomotive".  It's nice and cheap, and I'm pretty much following along on how he did things.

 :LittleDevil: The oven's not connected yet; it's just a convenient place to store the painted bits without getting dust on them while drying.  Funnily enough the one in the kitchen is cleaner and gets used at least four times a week...  Lots of scrubbing; I like cooking and baking but not in a dirty oven.

I was looking forward to a full shop session for a change...  Alas, that was not to be; a couple of days ago a damp patch appeared in the back driveway.  I didn't think too much of it; I thought it was just a remnant of some recent rains.  This morning it was looking like a fountain was about to erupt, and we haven't had any rain for a while and everything is bone dry, so there's definitely a problem:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5419.JPG)

After lifting the pavers and digging around, I discovered the source of the Nile...  the mains water pipe had ruptured  :facepalm2: .  That called for a trip to town to get stuff to repair the pipe, and after more work, things are fixed.  I left the hole open so that I can monitor things for a day or two; then I'll fill it up again and put the puzzle pieces back:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5421.JPG)
That lot's not going to do my water bill much good...

On to some engine work, and I started masking the cylinder block off:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5422.JPG)

A while later:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5423.JPG)
I'm not too concerned about the holes that are left open; a tap will easily clean excess paint from them.

I also prepared all the other bits that still needs primer.  The flywheel had a couple of blemishes and some rough spots that happened when the spray gun ran empty, so it was also given a good rubbing to get rid of those, and will get another thin coat of primer:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5424.JPG)

Doing that lot took quite a bit of time, and as it was starting to get a bit late, I decided to leave things at that and not start spraying it.  I don't want to rush things while spraying.  Tomorrow I should be able to get the rest of the primer coats done, and also start on the colour coat.   It's nice and hot here now with consistent 35-36oC temperatures predicted, so the paint will dry quickly.

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on October 26, 2013, 05:52:47 PM
Good progress there Arnold.  I'm still stuck with the cylinder feet.

What colour are you thinking of using?  I think mine will be cherry reddish.

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: Tennessee Whiskey on October 26, 2013, 05:56:01 PM
Ahh, the joys of home ownership :censored:. I really like the pavers. Aren't those repair couplings a blessing. Happy painting :cheers:

Whiskey
Title: Re: Arnold's take on the MEM Corliss
Post by: Don1966 on October 26, 2013, 06:13:45 PM
Nice to see some progress Arnold. Bummer about the plumbing and I am concern that the pipe is not deeper into the ground. It looks like it's just below the pavers. Weight could break it again.

Don
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on October 27, 2013, 05:03:44 PM
Thanks Vince.  I'm going for blue; will see what that turns out like...

Eric, you nailed it with the joys of home ownership.  There's always something to fix.  At least the couplings make things easy -

Thanks Don.  The pipe definitely is too shallow, but I can't blame the blokes who buried the pipe too much.  My house is on the side of a small hill, and there's mica bedrock about 3 inches below the pipe.  Digging holes or trenches on this property is not fun at all  :o


Sigh...  I was looking forward to a happy day painting.  Alas, the compressor motor made funny struggling sounds, let out the white magic smoke and tripped the overload switch when I started it up to fill the tank:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5425.JPG)
Fortunately I hadn't mixed up the paint yet...

Closer investigation, and the starting cap is toast.  The fact that the connecting terminal for the running cap is broken off wouldn't have done the starting cap any good either, and the bottom terminal on the overload switch must have had an iffy connection, as that overheated as well  :zap:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5426.JPG)

On closer inspection, the running cap isn't even the correct rating according to the spec sheet on the motor; it's just 45uF and should be 60uF.  So it's all a bit of a mess...  I'll get replacement caps of the correct ratings for both, and a new overload switch.  I was so disgusted, I closed shop and went to sort out a problem with the electric gate in front.  Sigh... That needs a new battery.  I guess the electrical suppliers are going to make a killing out of me this week.

It's true; Murphy was an optimist  :LittleDevil:

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: steamer on October 27, 2013, 05:52:32 PM
Ahhh Not so bad Arnold....I hate painting! :lolb:

Dave
Title: Re: Arnold's take on the MEM Corliss
Post by: b.lindsey on October 27, 2013, 08:45:37 PM
I had several pages to catch up on Arnold and its nice to see all the progress you have made. Not only the parts but the painting looks great as well. Will try to stay closer tuned to the progress :)

Bill
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on November 02, 2013, 04:41:39 PM
Dave, me too; it's one of those things that I want to get over and done with, though I must say this lot was a lot more enjoyable than I've done in the past.  It was just frustrating that I couldn't get on with it.

Thanks Bill - progress will be a bit slow though; the painting takes time to do...  I guess I'd better get going on the studs 'n stuff while waiting for the paint to dry.

I got the spares for the compressor this week, and bright and early this morning installed the lot.  Started her up, and something was still not right, and by the time I killed the electricity, the brand new starting cap had leaked electrolytic fluid again  :rant: .

So,there was another problem.  With the fan belt safety guard removed I turned the compressor over by hand a couple of turns, and it turned fairly easily, so the motor shouldn't have any problems starting up and getting to speed.  Next possible culprit: the centrifugal switch that's supposed to take the starting cap out of circuit once the motor is up to about 75% of speed.  I disassembled the motor, and found that the centrifugal switch had it's contacts fused closed, with lots of evidence of arcing:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5427.JPG)

After prying the contacts apart, I cleaned the burnt faces with a bit of emery, and started checking the mechanism out.  Operating the fly-weights by hand, I soon found out that the mechanism wasn't operating very smoothly, nor very positively.  Some tweaking of the contact spring plates soon had the positive operation of the mechanism sorted out, and a light application of dry lubricant in a couple of spots soon had it operating smoothly.
As the new starting cap was also now damaged, I made a mad dash to the supplier; fortunately they are open on Saturdays, but it was close to their closing time.  They were out of stock on the caps, but it's one of those few places where the owner still takes a bit of pride in customer care.  So he removed a cap from one of the floor display models, and handed it to me - free of charge.  On the way out of the shop, I bumped into a buddy of mine, and we retired to a near-by coffee shop for a bit of a face-to-face natter.  That's much nicer than using a phone.

Back home, with the motor assembled again and all the wiring sorted out, I gave it a run without the fan belt.  Started easily, and I could hear the centrifugal switch operate.  A quick test with a multimeter confirmed that things were running well.  After assembling everything back together - with some judicious application of thin rubber strips in a couple of places that always rattled a bit in the past, but were hard to get to, and the compressor is running sweeter than ever.  I think that the wire on the running cap had been broken since new, and without that cap in circuit to shift the electrical phase between the running coil and starting coil closer to 90o apart, the motor always struggled to start and get up to speed, thus loading the starting circuit for unnecessarily long periods.  Enough motor-theory...

I finally got back to painting.  The bare-metal bits received primer. The flywheel got a second coat after fixing some blemishes by rubbing down.

On to the colour.  I've had the primer for quite a while, so three weeks ago when I went to buy the colour paint, I went to the company that supplied the primer so that I could discuss getting an appropriate paint type to match it.  I wanted a semi gloss colour paint.  I soon found out that they're not quite as helpful as the tooling company I mentioned earlier in this post.  The "customer service" droid pointed me at the selection of compatible automotive semi gloss paints.  Pretty much none of them had a colour sample on the lid as is usual, so I asked about having some paint mixed up to specification. "No, we don't mix automotive semi gloss to specs, only gloss.  You'll just have to select from the shelf."  Before I could point out that the selection on the shelf had no colour dots, he'd turned his back on me and dashed off somewhere.
After digging around the tins of paint, looking for dried-out spillage droplets on the rims of the tops, I eventually settled on "Ford Blue" as the closest match to what I wanted.  The cashier was more helpful.  When I plonked the paint can and a can of thinners (chosen from next to the paint) down to pay, she told me it's the wrong thinners for the paint, got up and exchanged it for the correct thinners, and told me to mix it at about 20% thinner to paint for spraying.  A gentle enguiry as to where the "boss" was, and "He's not here today.  No, we're not allowed to hand out his cell number or email address." - Pity; I'd really liked to have a chat with him about customer service.  The cashier deserves better, and he needs to know what's going on - if he cares about his business.  Somehow, I don't think I'm going back to this paint shop.
Maybe I'm just getting more grumpy with age  :LittleDevil:

Anyway, the results of today's painting work:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5428.JPG) (http://www.nam-engineering.com/cm/displayimage.php?pid=8727&fullsize=1)

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: b.lindsey on November 02, 2013, 05:17:12 PM
Sounds like you had a busy morning Arnold. Glad you got the motor issue sorted out though, now the painting can resume :)

Bill
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on November 02, 2013, 05:56:58 PM
I am starting to like that blue.  Can't wait to see it all assembled.

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: NickG on November 03, 2013, 08:57:18 AM
Well done with the motor Arnold, I took the one to bits recently that will go on my shaper - it had an annoying rattle, the only thing I could put t down to was play in the centrifugal clutch mechanism - strange though as the noise happened suddenly - I always thought there was something rattling around inside it! Doesn't seem to be anything untoward so at least I know now, will just have to put up with the rattle!

Lol @ "customer service droid" !
Title: Re: Arnold's take on the MEM Corliss
Post by: gbritnell on November 03, 2013, 11:39:05 AM
Being a Ford man I'm partial to that blue anyway but it still looks good. With all the paint and brightwork it will look great.
gbritnell
Title: Re: Arnold's take on the MEM Corliss
Post by: Don1966 on November 03, 2013, 02:36:20 PM
Nice work getting your motor back running again Arnold, and I do like the blue it's my favorite color. Waiting to see it all assembled and running.

Don
Title: Re: Arnold's take on the MEM Corliss
Post by: cfellows on November 03, 2013, 03:23:14 PM
Just flipped through the entire thread.  A lot of darned nice work there, Arnold.  The Corliss is a really pretty engine and your example looks like it will be top shelf!  I do admire your patience.

Chuck
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on November 03, 2013, 06:54:14 PM
Thanks All  :praise2:

It's good to be back on track - though assembly is still quite a bit off.  It's me and nuts and studs next.

Nick, that phrase was blatantly borrowed from a couple of episodes of BOFH (http://www.theregister.co.uk/data_centre/bofh/)  ;)

Today was a good 'un.  After rubbing down some blemishes early in the morning, the last parts got a second coat of primer, and this dried fairly quickly, so by about 11:00 I sprayed the last of the top coat and set the parts out to dry:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5430.JPG)

At about 18:00, I took the last painted parts out; they were dry enough to handle (very carefully though) and took a group-shot:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5437.JPG)

The flywheel was the hardest part to get an even coat on - and there's some parts of the spokes where the top coat ended up too thick:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5438.JPG)
Those might thin out a bit more as it dries further - at least I'm hoping so.  If not, it'll be back to sanding and another coat of paint.

I'm quite pleased with how the cylinder block turned out:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5439.JPG)
Of course, the final verdict will have to wait for a bit, as it needs to dry further, and only once the masking is removed, will I get to see how well it actually worked.

I staged a shot of the cylinder block and cross-head guide to get a "feel" for things.  Like George mentioned, the colour should offset the bare metal bits nicely; I was scared it may be a bit light, but should do fine:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5440.JPG)

The flywheel, on the other hand, might be a bit "too blue".  From what I've seen, most of these types of engines had the entire flywheel painted, but it looks a bit overpowering and might need some form of toning down or additional detailing.  I'll see what it looks like all-assembled first though. 

As to the rest of the shop time today, most of that was spent contemplating how I'd go about making all the nuts and studs.  The engine would look OK with screws used as fasteners, but it would look better with more appropriate fasteners.  I don't quite share Jo's passion for making these though.  In my short model engine making career, I ended up doing this out of necessity rather than choice; simply because I could not easily get my grubby paws on commercial items.  Making a couple each time for one of Elmer's engines isn't too bad, but there's a lot more required here, and I may as well prepare for the future.  The contemplation turned into a couple of C-o-Cs, and near the end of shop time I started machining a bit.  Not a lot yet, but a bit.  That's a post for the tooling section though.

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: Jo on November 03, 2013, 07:19:36 PM
As to the rest of the shop time today, most of that was spent contemplating how I'd go about making all the nuts and studs.  The engine would look OK with screws  :hellno: used as fasteners  :slap:, but it would look better with more appropriate fasteners  8).  I don't quite share Jo's passion for making these though. 

Kind regards, Arnold

 :lolb: what gives you the idea I like doing studs. In my experience studs never live up to all the hype their only positive side is stud humor is fun  :mischief: and they give me something to do on a cold winter's night in my bedroom.

Jo
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on November 03, 2013, 07:56:02 PM
Arnold

I guess it is a bit late, but what do you think if you leave the rim of the flywheel unpainted?  That is what I intend to do on mine.

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: Maryak on November 03, 2013, 09:45:22 PM
Nice paint job Arnold  :ThumbsUp:

As an alternative to Vince's suggestion maybe some shallow rope grooves. They should cut through the paint OK and leave a nice contrast.

Best Regards
Bob
Title: Re: Arnold's take on the MEM Corliss
Post by: NickG on November 03, 2013, 09:55:14 PM
I would never have dreamt of painting the rim of a flywheel until I saw Jason's and Stew's engines which look excellent. When you think about it, it is more realistic for the whole thing to be painted. That said, I do still like some bright work - I like both schools of thought, on my latest engine I have painted the rim also. It could be an easy way to break up the blue if you decide there is too much. I think it'll look good once together.
Title: Re: Arnold's take on the MEM Corliss
Post by: mklotz on November 03, 2013, 09:56:14 PM
Maybe it's just me but that shade of blue just cries out to me for some pinstriping and detailing in a buttery cream color.
Title: Re: Arnold's take on the MEM Corliss
Post by: Tennessee Whiskey on November 03, 2013, 10:36:22 PM
I hate to agree with Marv, but, I agree. Detailed pinstriping in a dark hue of cream, almost to a faint gold hue.

Whiskey
Title: Re: Arnold's take on the MEM Corliss
Post by: mklotz on November 03, 2013, 11:43:05 PM
I hate to agree with Marv, but, ...

Ah gee, now I feel all lonely and unwanted. 
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on November 10, 2013, 02:04:03 PM
I thought I'd get a roasting from you Jo  >:D .  Have no fear; I'll leave the screws out.

Vince, thanks - I did consider that... And it may well turn out to be the better option - have a look at today's update and see what you think.  Taking paint off is not too difficult.

Thanks Bob.  The rope grooves is a good idea  :ThumbsUp: .  Unfortunately, the primer and top-coat combination will not work; it will leave white stripes from the primer showing.  :embarassed: More detail below.

Marv, I agree with you and Eric as well.  I can see it in my mind's eye.  Unfortunately, I'm having enough trouble just painting for now; pinstriping will have to wait for a future project.

Yesterday I removed all the masking from the bits:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5474.JPG)

The top of the cylinder block is a stuff-up; while removing the tape, it tore little chunks of colour paint from the primer  :facepalm2: :
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5473.JPG)

I put things together for a look-see to get a better idea of how it would look:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5476.JPG)

The cylinder block definitely needs repainting.  And I'll take the paint off the flywheel rim - it will actually look nicer when it's shiny.  Once all the stainless nuts and studs are added, that will also offset the blue and things should look OK then.

Gave my neighbour a helping hand this weekend - more paint work, but the pay is good; it comes in liquid form all the way from Scotland, and besides, the guy recently supplied me with a bunch of gratis pressure gauges:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5457.JPG)
The dog wasn't very impressed...

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: Don1966 on November 10, 2013, 02:39:42 PM
Oooooh! I like the way that looks Arnold, but I have to agree with the others. It does need some pin stripping and the flywheel rim would look good shiny.

Just my 2 cents Don
Title: Re: Arnold's take on the MEM Corliss
Post by: NickG on November 10, 2013, 05:04:26 PM
Yep on this occasion the flywheel rim will look better shiny I think. Looks great though.
Title: Re: Arnold's take on the MEM Corliss
Post by: Alan Haisley on November 10, 2013, 05:24:33 PM
Could practice pin striping on that trailer  :LittleDevil:
Alan
 
Title: Re: Arnold's take on the MEM Corliss
Post by: b.lindsey on November 10, 2013, 06:01:06 PM
Looking great Arnold. I agree also on the pinstriping, but practice on something else first. Looking forward to seeing it in its final form!!

Bill
Title: Re: Arnold's take on the MEM Corliss
Post by: mklotz on November 10, 2013, 06:44:24 PM
They make pinstriping tools but they're expensive and, I expect, difficult to find in Namibia.

Pinstriping tape is another option.  It's a cheat but easier to apply and control than paint.
Title: Re: Arnold's take on the MEM Corliss
Post by: b.lindsey on November 10, 2013, 07:21:08 PM
Here's a link for one Arnold, but as Marv says, may be hard to get there. Even with these it takes some practice to get good at it, but definitely easier that doing it freehand.

http://www.beugler.com/

Bill
Title: Re: Arnold's take on the MEM Corliss
Post by: zeeprogrammer on November 10, 2013, 10:56:56 PM
Hee hee hee. See what happens Arnold?
Some guy comes up with a nifty idea to improve one's model that you hadn't considered.
Then you start thinking about it.
You know it's a good idea...but it wasn't in your plans.
You'd like to...but you're not sure.

You're thinking about it. I know you are.
I'd be surprised if it hasn't invaded your dreams yet.

 :Lol:

It sure looks good Arnold. Quite beautiful.
Title: Re: Arnold's take on the MEM Corliss
Post by: Don1966 on November 10, 2013, 11:11:55 PM
Arnold the easiest way to learn pin stripping is with this http://www.amazon.com/Pinstriping-Made-Simple-Model-Engineering/dp/B003JUHHU4
Before you go looking at the price it is as easy as Ruby makes it look. Doing the flywheel even is a breeze. I have the DVD and love it, he tells you what you need to get it done. Of coarse I haven't made a project with it yet, but will be prepared when it comes up.

Don
Title: Re: Arnold's take on the MEM Corliss
Post by: Jo on November 11, 2013, 07:23:37 AM
Of course what they have not explained is the importance of getting the paint viscosity just right  :LittleDevil:

I would say you soon learn, but with the regularity that those pinstripers turn up at our club sales I am not convinced. But I am going to have to learn as I have a certain ploughing engine to paint in my future  :(

Jo
Title: Re: Arnold's take on the MEM Corliss
Post by: smfr on November 11, 2013, 06:46:02 PM
With a bit of practice you'll be pinstriping like these guys   :Lol:

http://www.youtube.com/watch?v=UsTIMxeO_ng

Simon
Title: Re: Arnold's take on the MEM Corliss
Post by: Jasonb on November 11, 2013, 06:53:39 PM
Its not hard to do by hand, here is one of a pair I did last week ;)
Title: Re: Arnold's take on the MEM Corliss
Post by: NickG on November 11, 2013, 09:03:48 PM
Wow pretty impressive on the complicated petrol tank shape! Flywheel looks great too Jason.
Title: Re: Arnold's take on the MEM Corliss
Post by: mklotz on November 11, 2013, 11:48:42 PM
With a bit of practice you'll be pinstriping like these guys

I could practice until the sun burns out and still not be able to do that.  I never cease to marvel at sculptors and artists who can, with a few deft strokes, characterize a feature or evoke a shape.
Title: Re: Arnold's take on the MEM Corliss
Post by: Tennessee Whiskey on November 12, 2013, 12:45:06 AM
Amen Marv. I think we practice the art of and true professionals perform the art of.

Eric
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on December 23, 2013, 07:02:06 PM
A belated Thanks All for your input  :NotWorthy:

It's been a long time since I got anything done on the Corliss  :-[ - things have been a bit hectic, and like I mentioned earlier, engine builds do tend to slow down when one is in the finishing straight...

The pin-striping is a nog-go for now; that's something I'll have a practice on at some point, but not yet.  After the hiatus to make the ER11 tool, I'm back on track on the engine though, and after a hectic past month, I jumped at the opportunity when my boss asked me if I'd like leave for the non-holiday days this week.  So I finally spent some time on the engine today.

A while ago I'd finished off the first couple of studs:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5595.JPG)

A quick trial fit:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5593.JPG)

With two machined-down M3 stainless nuts:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5594.JPG)
Obviously, the washers are way too big, and the nuts could do with a little finishing on the tops.

Today I addressed the paint mess on the cylinder block.  When trial fitting things, besides for the broken paint showing up the primer, there were small sections of bare metal showing in other areas.  So I decided that I'd rather mask off smaller areas and paint over it thinly - and then let the packings when I make them take up the difference.  So the block was smoothed down over some 600 grit emery, and smaller maskings applied:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5601.JPG)
I didn't re-apply primer; I just sprayed a single thin covering coat over that lot.  Maybe not good practice, but I'm a bit out of my depth here and just going by what I feel might work.

While the paint was drying, I machined down about 50 M3 nuts from 5.5mm to 4.5mm across flats - sticking them on a piece of copper wire to keep them together:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5602.JPG)

Then it was off to the lathe with them, to turn a chamfer on the top sides:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5603.JPG)

The nuts are not all the same thickness (cheapo supplier or something to that extent) so some appear to have more of a chamfer than others when viewed up close, but should not be too obvious once installed:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5604.JPG)

I also stripped the paint off the flywheel rim and sides with acetone.  I'll have to respray the inside of the rim with blue, and after a bit more finishing on the rim and sides I'll spray that with clear lacquer to prevent rust.  The shiny rim does break things up a bit and should look good once finished.  I might even be bold and try some gold paint on the hub to break things a bit there...  Anyway, I left off with this lot for today:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5606.JPG)
The pair of marigold gloves at least means I don't have blue fingers or nails after today's paint session  ;D

The cylinder looks quite a bit nicer, and from appearance, the flywheel should be OK too.  I have a bunch of studs left to make, a lot of M2 stainless nuts, and a nice regulator valve (for now).  There's also quite a bit of woodwork left to do on the base, and for some of that, I need to make a "tool", but I'll spare MEMbers from that build log, as the "tool" will be mostly in wood  >:D .

As an aside, I caught Shrek trying to check up on what everyone's doing the other evening:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5577.JPG)

Had a phone call a couple of minutes ago with an invite to a fairly remote location for the Christmas and Boxing Day, so I'll be a bit quiet on the forum for a while.

So, here's to a Happy Christmas Everyone (or a bah-humbug for those so inclined)  :cheers:

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on December 23, 2013, 07:32:21 PM
That flywheel with bare metal rim really looks good.

Enjoy the festivities Arnold.

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: ths on December 23, 2013, 08:18:14 PM
And a Merry Christmas to you too Arnold.

Hugh.
Title: Re: Arnold's take on the MEM Corliss
Post by: b.lindsey on December 23, 2013, 10:25:28 PM
Merry Christmas Arnold !  Love the picture of Shrek !!!   Of course the Corliss ain't too bad either :)

Bill
Title: Re: Arnold's take on the MEM Corliss
Post by: swilliams on December 24, 2013, 02:05:08 AM
Great stuff Arnold. Love the picture of your personal assistant on the tablet. Enjoy your Xmas

Steve
Title: Re: Arnold's take on the MEM Corliss
Post by: Don1966 on December 24, 2013, 04:17:04 AM
Love that blue Arnold and I can see Shrek is really into it. Merry Christmas to you bud.

Don
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on April 06, 2014, 06:12:42 PM
Wow... a quarter of a year since I posted an update to this project  :o

 :-[ A belated thank you for the festive wishes Gents - I thought I'd replied...

It's about time I got back to the Corliss, and at least finish it off to the "Simple" stage.  Going's a bit slow in the shop of late, but I'm not unhappy about that - several good things have been happening.

Besides the fasteners, the outstanding items for the engine are:
- Base - this still needs finishing off.
- Regulator valve: I'm saving this for in-between to break the boring bit of making fasteners  ;)
- Piston ring: I'll be making this from Teflon that I already have in stock.  Should be a fairly quick turning operation.
- Gaskets - Need to spend some time in front of the computer for that, and maybe make up a punch for the holes.
- Paintwork: Pretty much done, except for some touch-up needed on the flywheel.  I'm also thinking of giving the bare metal on the flywheel a coat of clear lacquer to prevent rust.

After making the box tool to trim the stainless rod down a bit and realizing how blunt my M3 die had become, I bought a new die yesterday.
Today I spent a couple of hours in the shop making studs - this now went _much_ easier and quicker with the sharp new die and the slightly thinned rod.

At some point I took a break from the studs, and decided to trim down some washers as well.  The 3mm washers I have has an OD of 7mm which is much too large; they needed to be trimmed down to 5.3mm OD to match the nuts I made earlier and also fit in all the locations needed.  The washers has an ID of 3.2mm.  This meant simply sticking them on a bit of 3mm threaded rod to turn down would leave many of them off-center.  So I made a quicky arbor from 3.2mm brazing rod by threading about 5mm at the end and a couple of spacers to slip on either side of the washers - this left things more concentric for machining:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5975.JPG)

The rod was then chucked in the collet chuck on the lathe, and the spacers and washers tightened against the collet nose with a nut.  This is not very rigid, but a couple of fine turning passes with a very sharp toolbit easily turned things down:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5976.JPG)

I just slipped the washers onto a bit of binding wire to keep them together:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5977.JPG)

I amassed a good hoard for the day - there's only about 5 M3 studs to finish of now.  I'm not going to bother making studs for the 32 M2 ones - those I'll make from all-thread later:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5979.JPG)

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: Kim on April 06, 2014, 09:51:15 PM
Good to see you making some progress on your Corliss there Arnold.  You've got a nice group of studs and washers ready for assembly!

Kim
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on April 06, 2014, 10:25:57 PM
Good to see you back at it Arnold.  As for 3mm washers I thought I would use commercial 3mm spring washers which are just the right size.  I doubt I can find 2mm threaded rod locally so I might use long 2mm bolts and cut the head off.

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on April 08, 2014, 10:23:27 PM
Thanks Kim & Vince  :)

Vince, I can't get the spring washers locally... - but that should work fine, although they might appear a bit thick.  I know the M2 threaded rod is quite freely available in the UK in 300mm lengths, and not too expensive in GBP either.  Don't know about the shipping costs to Malta though, so that might be a consideration.  I'll just make up my own; shipping and the current exchange rate is a killer for me, so some effort is worthwhile  :)

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on April 20, 2014, 06:47:33 PM
Things are going slow, but the end of the fastener making is in sight...

I made up some M2 sections of threaded stainless rod.  The rod I got from flux-coated stainless steel stick welding rods; it's simple to crack the flux off and clean up the rod with some Scotch-Brite.  Then I threaded them with the tailstock die holder running the Myford under power on medium back-gear speed:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5980.JPG)

As usual, I cheated a bit, and decided to make the M2 "studs" more as little "bolts".  I set up the small lathe with the back stop to get a consistent length, and ground up a bit of 4mm square HSS toolbit to make a shaping/parting tool.  That enabled me to make the bolts with pre-shaped heads, as well as leave a suitable "tip" to provide a good thread start for the next section of bolt at the parting line.  I threaded a bunch of nuts on the threaded rod, and supported the trailing end in a bit of brass pipe in the tailstock chuck.  To make sure each nut would stay put at it's location on the bolt-in-making,  I simply fouled the threads next to the chuck slightly with a blunt side-cutter each time, and then turned a nut over the fouled threads and up to the collet nose.  The next photo was taken just before plunging in the cross-slide to part the rod and shape the bolt top:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5983.JPG)

That made things quite easy to makeup the 32 needed and a couple extra bolts:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5991.JPG)

I've also slowly started putting things together:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5981.JPG)

(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5982.JPG)

(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5992.JPG)

Hopefully I can get some more paintwork done tomorrow, as well as a bit of work on the base...

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on April 20, 2014, 10:58:33 PM
Looking good Arnold.  Hopefully I can continue  mine in the not too distant future.

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: Baron on April 21, 2014, 12:27:08 PM
Hi All,
Arnold a very impressive engine !  I'm in agreement with others the blue is a bit intense.  It could do with some fine lining to break it up a little.

There is a Corliss engine running in Markham.  It has a flywheel with rope grooves around it which has been painted, in this case black.
I was looking at the valves that you made and comparing them to the original ones.  I had a good discussion with the chap that runs this engine and gleaned a lot of information about the engine.

I did a sketch of the original intake valves and the actual shape of them.  I found it interesting to learn the reason why they were shaped as they were.  It seems that gas flow was considered important in 1850's in the interests of efficiency.

Title: Re: Arnold's take on the MEM Corliss
Post by: pgp001 on April 21, 2014, 02:21:59 PM
Baron

I am building a 1/16 model of the Markham Corliss engine "Agnes". Was it George Dickinson you were speaking to ?
There is not much I don't know about that flywheel by the way :)

I see from your profile you live in North Yorks, probably not to far from me in West Yorks.

Phil
Title: Re: Arnold's take on the MEM Corliss
Post by: Baron on April 21, 2014, 08:43:38 PM
Hi Phil,

Yes it was George.  Nice fellow to talk to.  He seems to know his stuff about Agnes.  He spent quite a bit of time explaining various things to me.  Especially when I mentioned that I was interested in making a model of one.

Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on June 02, 2014, 07:05:47 PM
Thanks Vince - since my last post you've been making good progress

Baron, thank you for the compliment, comments and information .  If you have photos of the Corliss at Markham, please do share them. I agree with you; there's a lot more to true Corliss valving than shown here.  In fact, the simplistic valve design for this build is down to the parameters the design team set out with - to design an engine suitable for fairly new to intermediary level model engineers who wants to build a simplified working, but not fine-scale, model of a great looking engine for running on compressed air.  IMHO the plans as-is can be used and adapted to a fine-scale working model, and that includes going to the extra effort of making the valves true-to-form, which would include converting for proper live steam - including (to me the most interesting part of the Corliss valving besides dash-pot cut-off) leaving room for valve-lift to prevent hydraulic lock.

Phil, thanks for checking in - is there any possibility you could share some photos of your build?  Pretty Please?

Things have been hectic, and I didn't have a lot of time for our hobby of late...  I found some time here and there to make a couple of very insignificant bits, and some of the tasks left on the base required making bits of tooling of a very different nature...

When I made the piston, I mentioned that I'll be using a piston ring.  This is the first engine I've built that will use a piston ring, and I'd decided to make it from PTFE/Tufnol rather than graphite packing (I've found a lot of hens' teeth in my neck of the savannah, but graphite yarn/packing still eludes me) or cast iron rings.  This engine will never be used on live steam, so a plastic based ring seemed the best solution.  I have about a meter (just over 3 feet) of 25mm (1") Nylon based carbon impregnated plastic, so I cut a bit off it and started machining with a sharp HSS toolbit:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5997.JPG)
Comes with strings attached...

Surprisingly, underneath the strings the finish was quite good and after a bit of boring, I had things down to a suitable size for parting off a ring:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_5998.JPG)

To slit the ring, I used a home-made 0.2mm thick "slitting saw"  See if you can spot the issues with it before reading the comment below the image:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6000.JPG)
A couple of years ago when I made it, I formed the teeth the wrong way around, so I have to run the mill in reverse to use it...

The finished ring:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6001.JPG)

As mentioned, I had to make a bit of tooling of a different nature - I didn't go about it entirely delicately, and while hogging off some steel to make L-shaped clamps, some inattention at the start of a cut resulted in a broken 16mm roughing end-mill:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6008.JPG)
Haven't broken any cutting bit that big yet - nearly scared some brown stuff out!

Anyway, after finishing that bit, it became a part of a skid mounting for my router:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6009.JPG)

I won't bore you too much with the wood stuff - if you're interested, there's a bit more  here on RouterForums.com (http://www.routerforums.com/show-n-tell/46110-my-first-ever-use-router-2.html#post384876).

A bit more wood-work saw the base pretty much finished:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6020.JPG)

Some elbow-grease with teak oil and furniture wax brought out the colour and grain of the wood at a dull lustre; I don't want the base too shiny.  This is outside in natural sunlight:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6022.JPG)

I'll have to look at the white-balance settings on my camera...  This was taken inside under fluorescent shop lighting later on with bits of the engine plonked down on it:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6023.JPG)

Not a lot left to do now; some ornamental brass/bonze feet for the base, and a bit of pipe-work and valve.  I'm dying to start on a new engine project, but I promised myself I won't before this one's done...

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on June 02, 2014, 07:42:51 PM
Nearly there Arnold.  Did you finish the studs?

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: Baron on June 02, 2014, 09:11:48 PM
Hi Arnold,

I've not forgotten about your request for photos of Agnes.
Unfortunately my health hasn't been too good of late and I need to get down to Markham to take some pictures.

That wooden plinth looks great, and I like the router jig.  I'll have to make one of those it looks to be very useful.

Title: Re: Arnold's take on the MEM Corliss
Post by: b.lindsey on June 03, 2014, 02:02:45 AM
Nice work on the base Arnold...and the engine ain't too shabby either :) Looking forward to seeing all the part together and soon enough under power as well!!

Bill
Title: Re: Arnold's take on the MEM Corliss
Post by: Don1966 on June 03, 2014, 02:33:38 AM
What Bill said and I just love the color. Just Awesome Arnold and I like................ :praise2:


 :popcorn:
Don
Title: Re: Arnold's take on the MEM Corliss
Post by: Jack B on June 03, 2014, 04:03:10 AM
Nice work Arnold                          Jack
Title: Re: Arnold's take on the MEM Corliss
Post by: Kim on June 03, 2014, 06:21:15 AM
It's looking good Arnold.  Really like the base.  I think that dark wood will set the engine off nicely!
Can't wait to see it all together!
Kim
Title: Re: Arnold's take on the MEM Corliss
Post by: Baron on June 03, 2014, 05:55:23 PM
For Arnold,



Title: Re: Arnold's take on the MEM Corliss
Post by: Roger B on June 03, 2014, 06:23:36 PM
That is a magnificent engine  :ThumbsUp:  :ThumbsUp: Thank you Baron for taking and posting.

Arnold, the wooden base complements  your model splendidly  :praise2:  :praise2: looking good not long now till the first run.
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on June 03, 2014, 07:45:00 PM
Thanks Vince - all the fiddly studs, nuts and washers are done.  Just the final mounting studs for the base left to do, but those should be quick.

Baron, thank you; I hope your health picks up soon! - Thanks for the photos - there's many new questions surrounding them, but I'll hold back for now...  The router skids are very useful - I have a hunch I'll use that quite a bit in future, and part of the assembly will be used to table-mount my router as well.

Bill, Don, Jack, Kim & Roger - thanks gents.  There's not a lot left to do, but it might still take a while, as my hobby time is down to literally an hour or two a week at the moment... Hopefully that will change in a couple of weeks' time though.

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: Jo on June 03, 2014, 08:03:51 PM
..., but it might still take a while, as my hobby time is down to literally an hour or two a week at the moment... Hopefully that will change in a couple of weeks' time though.


Decorating or something more interesting  :mischief:

Jo
Title: Re: Arnold's take on the MEM Corliss
Post by: Baron on June 03, 2014, 09:33:00 PM
Hi Arnold, Guys n Gals,

I have around thirty photographs.  Since the forum will only allow eight, those were the first.

Here is the second eight...
Or not since it won't let me post the next ones.

Anybody that wants to see the others please PM.

Thanks all.


Title: Re: Arnold's take on the MEM Corliss
Post by: zeeprogrammer on June 03, 2014, 11:12:27 PM
I won't bore you too much with the wood stuff -

Quit that! Without wood stuff...we wouldn't be doing what we're doing.

Looking great Arnold. I always enjoy reading your threads.
Title: Re: Arnold's take on the MEM Corliss
Post by: Baron on June 04, 2014, 02:56:45 PM
Another one...  Maybe
Title: Re: Arnold's take on the MEM Corliss
Post by: Jo on June 04, 2014, 03:23:16 PM
 :o What are they doing with Agnes she is rusty  :hammerbash:

Jo
Title: Re: Arnold's take on the MEM Corliss
Post by: Alan Haisley on June 04, 2014, 07:20:38 PM
Agnes needs her own thread. Maybe in Engines in Showcase. Then all her pictures will be closer together for easier viewing.

Alan
Title: Re: Arnold's take on the MEM Corliss
Post by: Baron on June 04, 2014, 08:30:13 PM
:o What are they doing with Agnes she is rusty  :hammerbash:

Jo

I don't think they can do too much about that.  It gets very hot just there on the end of the valve stem.
Anyway just for information:-
Markham Grange Steam Museum is privately run and owned.  It relies upon donations and the goodwill of the few volunteers for its upkeep.  It steams once a week and attracts visitors worldwide. 
This is its web site address.   www.markhamgrangesteammuseum.co.uk


Title: Re: Arnold's take on the MEM Corliss
Post by: Baron on June 04, 2014, 08:33:30 PM
Agnes needs her own thread. Maybe in Engines in Showcase. Then all her pictures will be closer together for easier viewing.

Alan

I agree !
But since the forum won't allow more than eight pictures it's a problem.
But I've sneaked another picture in. :-)

Just for Jo...
Title: Re: Arnold's take on the MEM Corliss
Post by: Jo on June 04, 2014, 09:12:08 PM
The forum software only lets you add 8 pictures in each post not the thread  ;)

Governor  :embarassed:

Jo
Title: Re: Arnold's take on the MEM Corliss
Post by: Baron on June 05, 2014, 01:42:19 PM
The forum software only lets you add 8 pictures in each post not the thread  ;)

Governor  :embarassed:

Jo

In that case I must not be doing it right.
I've found that I can attach a single picture, but clicking on "more attachments" gets ignored !

I'll try again with this post.

No !  Its taken just the one picture...

Title: Re: Arnold's take on the MEM Corliss
Post by: geoff_p on June 05, 2014, 04:17:51 PM
In that case I must not be doing it right.
I've found that I can attach a single picture, but clicking on "more attachments" gets ignored !

I'll try again with this post.

No !  Its taken just the one picture...

And just look at the SIZE of your one picture - Six-hundred and odd Kb, whereas Alan's images (Test 1) are a much more reasonable 60~70 Kb, and he can attach several for far less 'cost' than your single image.
Geoff
P.S. Try using Windross "Image Resizer".  It's free, simple and works!  (One of the few Windose things that fulfills those criteria.)
Title: Re: Arnold's take on the MEM Corliss
Post by: Alan Haisley on June 05, 2014, 04:34:07 PM
I deleted my tests so they wouldn't clutter up a good thread but what I found is that I can click on "Attachments", then either click on "More Attachments" ahead of time before browsing to my pictures or I can do it one at a time, i.e., browse to a picture, select "More Attachments" and browse another. Too large (in bytes) an individual image or too many bytes overall and I get various kinds of errors without my pictures getting posted. There MAY also be some condition that occurs if I get multiple posts in too fast but this may just be part of either too many attachments or some of the attachments being too big.
In every case I don't get Baron's condition where after he makes one attachment he can't select "More Attachments" so I'm still not sure what that's about. I didn't analyze the sizes in bytes of his pictures so there may be another situation that I just missed.

Alan
Title: Re: Arnold's take on the MEM Corliss
Post by: Jo on June 05, 2014, 04:53:52 PM
There is a size limit to the attachments, Arnold can tell us what it is.

 :offtopic:

But lets get this thread back on subject: Arnold over to you we are looking forward to seeing more progress  8)

Jo
Title: Re: Arnold's take on the MEM Corliss
Post by: Alan Haisley on June 05, 2014, 05:04:51 PM
But lets get this thread back on subject: Arnold over to you we are looking forward to seeing more progress  8)

Jo

 :popcornsmall: Yeah, popcorn's running low.
Title: Re: Arnold's take on the MEM Corliss
Post by: pgp001 on June 05, 2014, 05:16:04 PM
Just to avoid any confusion, the photo in reply 439 is not "Agnes" by the way.

Phil
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on June 05, 2014, 07:54:49 PM
Thanks all who checked in  :)

Thank you for the photos Baron -  :headscratch: Don't know why you're having problems with the attachments though.  The forum is set to allow up to 8 attachments per individual post up to a total of 10 Megabytes for all eight, without an individual size restriction...  Check your PMs for my email address - then you can forward all the photos to me, and I'll put them up in a separate post like Alan suggested  :ThumbsUp:

Quote from: Jo
Decorating or something more interesting  :mischief:
::) Certain things didn't work out, but OTOH there won't be redecoration needed now :LittleDevil:.  I'm finishing off a couple of work projects and hopefully getting back to a somewhat more human (or should that be humane?) work schedule.  I have to take some leave for a change - my leave days are maxed out...

Quote from: zeeprogrammer
Quit that! Without wood stuff...we wouldn't be doing what we're doing.
Be careful what you wish for Zee...  I might just be tempted to do Elmer's #01 at some point and show all the gory detail.  Hmmm... Come to think of it, the #37 should also look stunning if done in a dark wood and brass/bronze combination and some fine detail added...  Any takers out there ?

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: Jo on June 05, 2014, 09:01:10 PM
but OTOH there won't be redecoration needed now :LittleDevil:.

I've done the redecorating and I can tell you that doesn't work either  :-\

The best use of leave I have found is to provide more time in the workshop  :pinkelephant:

Jo
Title: Re: Arnold's take on the MEM Corliss
Post by: Baron on June 05, 2014, 09:50:27 PM
Just to avoid any confusion, the photo in reply 439 is not "Agnes" by the way.

Phil

Hi Phil,

Yes your right.  There are a couple of photos that are of a model Corlis engine and not "Agnes".
It was right behind me.  I spotted it when I turned round, I thought it was interesting so I snapped a couple of pictures of it.
Sorry for any confusion.

Title: Re: Arnold's take on the MEM Corliss
Post by: Baron on June 05, 2014, 09:53:30 PM
Thanks all who checked in  :)

Thank you for the photos Baron -  :headscratch: Don't know why you're having problems with the attachments though.  The forum is set to allow up to 8 attachments per individual post up to a total of 10 Megabytes for all eight, without an individual size restriction...  Check your PMs for my email address - then you can forward all the photos to me, and I'll put them up in a separate post like Alan suggested  :ThumbsUp:

Kind regards, Arnold

Done !  Check your mail.

Title: Re: Arnold's take on the MEM Corliss
Post by: Baron on June 05, 2014, 10:02:04 PM
In that case I must not be doing it right.
I've found that I can attach a single picture, but clicking on "more attachments" gets ignored !

I'll try again with this post.

No !  Its taken just the one picture...

And just look at the SIZE of your one picture - Six-hundred and odd Kb, whereas Alan's images (Test 1) are a much more reasonable 60~70 Kb, and he can attach several for far less 'cost' than your single image.
Geoff
P.S. Try using Windross "Image Resizer".  It's free, simple and works!  (One of the few Windose things that fulfills those criteria.)

Thanks for your notes Geoff,

Sorry I don't use Winblows...  I'm a diehard Linux user and have been for many years.  I don't have the time to be continually having to maintain a computer OS and fighting virus, phishing etc.  Linux does all the things you mention and more, but thanks for the suggestion anyway.  :-)

One of the reasons for posting large high detail photographs is just that "High detail".  People building this engine want to be able to look at the particular details that are important to them.

Title: Re: Arnold's take on the MEM Corliss
Post by: Maryak on June 06, 2014, 04:54:02 AM
Testin addin fotos
Title: Re: Arnold's take on the MEM Corliss
Post by: pgp001 on June 06, 2014, 06:40:58 AM
One of the reasons for posting large high detail photographs is just that "High detail".  People building this engine want to be able to look at the particular details that are important to them.

Sorry this has strayed off topic but:-

Correct me if I am wrong but I think the "People" building this engine is just me. There are no more castings out there that I know about, and I have the patterns.
If there is another one being built from scratch I would love to know about it please.

Cheers
Phil
Title: Re: Arnold's take on the MEM Corliss
Post by: Steam Haulage on June 06, 2014, 08:05:12 AM
Phil,
I presume you are referring to the MEM Corliss when you say 'this engine'. What are the castings you refer to?
I am in the early stages of the build.
As opportunity presents I have obtained most of the materials I shall need.
You might have seen my initial turning of the flywheel from solid. I've not posted for some months as I'm going through the set-up of my workshop, acquiring a new mill and lathe making all the bits and pieces which I used to have but which disappeared in a family break-up. This weekend should see some progress though as I attempt to mill the spokes (or rather the spaces between).

Jerry
Title: Re: Arnold's take on the MEM Corliss
Post by: Baron on June 06, 2014, 09:22:10 PM
I'm in the process of attempting to design a four cylinder corlis style engine.  Rather than having the cylinders in series putting them vertically side by side in the style of a marine engine.  Whether it gets anywhere is yet to be seen.

Sneaking in another picture...  The big beam to the very left in this picture is for the last engine that will be restored at Markham.

 
Title: Re: Arnold's take on the MEM Corliss
Post by: pgp001 on June 07, 2014, 09:09:29 AM
Phil,
I presume you are referring to the MEM Corliss when you say 'this engine'. What are the castings you refer to?
I am in the early stages of the build.
As opportunity presents I have obtained most of the materials I shall need.
You might have seen my initial turning of the flywheel from solid. I've not posted for some months as I'm going through the set-up of my workshop, acquiring a new mill and lathe making all the bits and pieces which I used to have but which disappeared in a family break-up. This weekend should see some progress though as I attempt to mill the spokes (or rather the spaces between).

Jerry

Hi Jerry

I was actually referring to the Pollit & Wigzell engine "Agnes" ie the one which Baron has been putting some excellent closeup detail photo's recently.
To my knowledge there are only three models of Agnes in existence, two were built by the late Peter Southworth, and I am slowly building the third one.
One of Peter's was sold at auction in 1995 and never been seen since, the other one is on display at the Northern Mill Engine Society in Bolton Lanc's.

So you see why I would be interested if anyone else is building that particular engine.

Phil
Title: Re: Arnold's take on the MEM Corliss
Post by: Steam Haulage on June 07, 2014, 10:56:30 AM
Phil,

Now I understand. My assumption was based on the fact that this thread is a build of the MEM Corliss and that Baron's photographs were of details on Agnes which could be of use to MEM Corliss builders. (You know what they say about assumptions)

Like you I am very interested in Baron's pictures, he has kindly sent me the complete set.
As I am not too far from Agnes herself I am hoping to visit, on a steaming day if possible, equipped with a fully charged camera and a notebook. I am concerned to get the smaller details as Peter Southworth's excellent book seems to be more focused on the GA of the engine and its history.

It is not my future intention to build a copy of Agnes, more to set-out to make my own design of horizontal engine, incorporating some of my own thoughts and seeing why they don't work.

Thanks for the explanation
Jerry
Title: Re: Arnold's take on the MEM Corliss
Post by: Baron on June 07, 2014, 02:16:52 PM
Hi Guys,

Not just to see "Agnes" but to enjoy all the other very fine specimens of engines from the age of steam !  Markham is very much worth a visit and the adjacent garden centre is sure to be enjoyed by the ladies.

 
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on June 08, 2014, 10:56:44 PM
Thanks all who replied  :)

The best use of leave I have found is to provide more time in the workshop  :pinkelephant:
;D - That's true Jo - though I can really do with a proper holiday for a change...

At least I had a bit of shop time over the weekend...

A bit of work was done on the mounting feet for the engine base - this is not on the plans, and will depend on each builder's own needs.  Basically, the base needs to be quite thick, as the flywheel protrudes a good amount below the engine base level.  I could have done more woodwork and made a riser "box" to go beneath the base plank, but opted rather for some riser feet.
Some 25mm (1") bronze was given a quick clean-up to get rid of the outer skin:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6025.JPG)

Then I used a quickly-ground round nose form tool to trim the end down - after checking on the lathe's leadscrew handwheel where the rear parting tool contacted the end of the workpiece, as well as noting the setting on the cross slide:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6026.JPG)

An additional form cut was made at a shallower setting - and the length once again checked off the leadscrew handwheel, and a disc parted off.  Five more followed using the same readings, and I had this lot:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6027.JPG)

I then bandsawed six 26mm long slugs off some 16mm bronze, and faced one end of each, as well as drilled a 5mm hole through them.
This left the "problem" of facing the other side of each to get them the same length.  Up to now, I've always managed to find some way to do this type of job, but everything was just at odd lengths and wouldn't fit chucks for easy repeatability, so I first made a quick tool...

I used a normal MT2 center to set the cross slide to the same angle as the Morse taper.  The scrap aluminium in the chuck end was just faced and center drilled so I could mount the MT2 center, and I indicated the top slide angle from that:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6028.JPG)

A handy bit of 20mm stainless was turned down a bit and then I turned the taper on it with the top slide:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6029.JPG)

One advantage of screw-on chucks are that one can actually unscrew the chuck to check things:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6030.JPG)

Far from a perfect fit - but close enough for this job:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6031.JPG)

The end was then drilled and tapped for M10 thread - to add a draw-bar, and next it was mounted in the lathe's spindle with a draw bar through the headstock.  Then I faced it dow to a thin flange at the nose end, and drilled and tapped it for M6:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6032.JPG)

This makes a rudimentary back stop that fits inside all of the lathe's chucks, and with a cap screw, or as time and needs dictate other bits to screw in there, a way to set things at fixed depths in chucks - here I just used a cap screw to set a quick depth on it before screwing back the chuck:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6033.JPG)

With that, it was easy to face the rest of the bronze slugs to the same length:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6035.JPG)

The bottom side of each of the discs turned earlier received a generous counter sink - I did that on the small lathe, as it's chuck conveniently gripped at that size:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6036.JPG)

For Saturday, this lot ended my shop session - not much to show, but it was a good session:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6037.JPG)

On Sunday I made a quick arbor for the 16x26mm bronze slugs, and skimmed the cruddy outside layer off - down to 15.2mm OD.  Then I did some calculations...
15.2 x 3.142 = 47.76 - close enough to 48mm circumference.  Hmmm... That was conveniently divisible by 12 - so I could make 12 "flutes" on each at a 4mm spacing.  To have things appear symmetric, that would leave 2mm flutes and gaps.  Digging through my selection, I decided to use a 3mm ball nosed cutter to cut the flutes - but that would leave only 1mm between the flutes...
Some more maths - how deep did I need to cut with the 3mm ball nose cutter to have the flutes about 2mm wide?:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6045.JPG)
Before the phi lands in the soup - I used pretty rough math, and rounded some things in between while going along.  It was close enough for this job.

I then proceeded to cut 12 grooves into each workpiece with the ball-nosed cutter:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6040.JPG)

A while ago, I was asked by a fellow member to sometimes include wider shots of the machine-setups I use, so I snapped this:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6041.JPG)
This setup is only good for very light work - there's not a lot of support for the workpiece, and the long overhangs will easily lead to lots of vibration issues for bigger cuts.

After a bit of spit 'n polish, I added some bits of 7mm tubing to the "feet" - to match holes I'd drilled into one end each of the uprights.  A drop of bearing retainer keeps it together:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6042.JPG)

A final bit of cleanup, and some more bearing retainer later, and I have six feet for the base:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6043.JPG)

It should look OK once mounted to the base:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6044.JPG)

That ended my shop time for the weekend.  A hectic work week is about to commence, and I'm already booked to work on next Saturday as well, so I don't think there will be updates soon...

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on June 09, 2014, 04:43:02 AM
Good progress Arnold.

I loved that backstop.

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: Jo on June 09, 2014, 07:04:15 AM
Bronze for the feet  :o That is rather expensive stuff to be using for feet, it looks like a purchased bit as well  :disappointed:.

I have a good stock of bronze came from an old boat prop shaft, it is rather yellowier than that good stuff you are using there. But the price was right  ;D

Jo
Title: Re: Arnold's take on the MEM Corliss
Post by: Baron on June 09, 2014, 03:14:45 PM
Hi Arnold,
Those legs look very posh.  :cartwheel: :cartwheel: :cartwheel:   I really like them.  That fluting sets them off nicely.
In the picture they look as if they are made from gold.



Title: Re: Arnold's take on the MEM Corliss
Post by: Baron on June 09, 2014, 03:20:52 PM
Hi Guys n Gals,


Whilst I remember...   There is a steam engine meeting this weekend at Markham.  I'm told that there will be a portable track laid and rides weather permitting.  I will be there with a bit of luck.


Sneaking in another photo !



Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on June 29, 2014, 07:42:03 PM
Vince, Jo & Baron, thanks for checking in  :)

The backstop was a real quickie - but I have a hunch I'll be using it a lot.  Not nearly as nice as Don's!

Bronze for the feet  :o That is rather expensive stuff to be using for feet, it looks like a purchased bit as well  :disappointed: .
Yes - purchased phosphor bronze...  Funnily enough, that's quite a bit cheaper and more obtainable  here in Windhoek than brass - and about the same price as stainless steel and cast iron.  Apparently the mining industry here in Namibia uses quite a lot of the stuff, so i think that's why it's "reasonable" here.
I could have used aluminium, but seeing as there's not a single bit of that on the rest of the engine, I went the more expensive route.  Could possibly have made them from wood as well, but there's a couple of things I want to get in place before doing too much wood-work in the shop...

It seems everyone building these "MEM Corliss" engines are going about it fairly slowly...  For me, work, a trip to South Africa for a course and exam, and a bout of flu last weekend has kept me out of the shop.  I managed to steal a couple of hours today though, and made a start on a regulator valve.  That's not on the plans, but I want it to add some more interest to the engine and "break the blue" a bit more.

Most of the shop time went on doing a bit of research into valves, digging around the stock pile to see what I had available, and coming up with a plan.  For the most part, it's based on George Britnell's (http://www.homemodelenginemachinist.com/f31/small-globe-valve-how-make-4377/) valve design, but I'm adapting the sizes and threads to suit what I have available.

I free-hand turned some 16mm brass - I didn't think it would be much use for me to make up a form tool for this job, as I'm unlikely to make many valves of this size in future:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6057.JPG)

After some work with a file to blend in the curves, followed by emery to smooth  things, it was off to the mill and dividing head for the hexagonal heads:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6058.JPG)

That was followed with a cross-drilled 4mm  hole with a 7mm counter-bore for soldering in the connector pipe later:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6059.JPG)

After parting it off the parent stock, my shop time was up  :'( - so this is what's left for today's effort:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6060.JPG)

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: Baron on June 29, 2014, 08:03:13 PM
Hi Arnold,

I like that valve body.  The curves look very good.  I know you said you did it freehand !  Until I realised you meant manipulating the cross slide I thought that you had used graving to do it.  Either way, it's nice.
 
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on June 29, 2014, 10:08:12 PM
Quote
are going about it fairly slowly...

I love that Arnold. That must be the understatement of the year. :Jester:

Where are you going to put that valve?  On top of the cylinder block?

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: Don1966 on June 30, 2014, 12:02:10 AM
Gee Arnold, somehow I missed the post about the feet. I love them and a nice addition to an already beautiful setup. The valve came out great also.  I love it when I can do some graving.

Don
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on July 06, 2014, 07:21:55 PM
Thanks Baron, Vince & Don

Yes - just free-style using the cross-slide and carriage...  Graving and spinning are two lathe disciplines I still want to get around to!

Vince, yes - the valve will go on top of the block.  I'm not sure how it will look though; I hope it comes out OK.

I managed to grab a couple hours shop time over the weekend.  First off was to finish the valve body - it needed some threading done on the other end.  To mount it, I used an M6 cap screw shoved through the rear of the ER collet - not very accurate, but good enough for this job:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6075.JPG)

The valve body was then screwed onto that and tight up against the collet face, and the other end opened about 4mm deep to 5mm diameter and tapped M6 for the incoming air line fitting:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6074.JPG)

Next up the valve spindle.  A bit of 6mm stainless steel rod was chucked up in the collet chuck with about 10mm extending from the chuck, and the end turned down to 3mm and threaded M3 with a tailstock die holder.  Then I extended the workpiece further out and turned an 18mm long section down to 4mm:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6076.JPG)

After extending the workpiece further out again, I threaded a short section M6 - once again with a tailstock die holder:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6077.JPG)

I forgot to take a photo of the next step...  I used a V-shaped tool to turn off a section of the threads close to the lathe headstock, and finally, with the top slide set over to 30o "parted" the workpiece off using the V tool.  A later photo shows the result.

Next up it was the double-ended adapter that keeps the spindle in place and help form the spindle packing.  I started that from some 10mm hex brass and (stupidly) formed most of it in one go and drilled the hole for the valve spindle:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6078.JPG)

That was parted off, the brass in the chuck faced nicely and drilled and tapped M6 to fit the threaded end of the workpiece.  the workpiece was then screwed into that so that I could thread the other end for the pack nut.  Easy, no?...
While threading the other end, things got a bit stiff - and not listening to Mr. Gut Instinct who told me to stop, I gave it another turn.  Just to show that things do go wrong, here's the result:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6079.JPG)
Fortunately, it was easy to remove the broken bit from the die nut - the hex helped a lot.

I called it a day for Saturday at that point - there was a cold front moving in and the shop became unbearable.
The collection of parts for the valve stood at this (including the broken bit):
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6080.JPG)

This will give an idea how things go together:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6081.JPG)

Made it back to the shop this afternoon... 

I've always struggled with silver soldering -  mostly because I'm inclined to use too much flux and solder, and the solder ends up going everywhere.  Today I spent some time carefully assembling the bits with just a little flux, and with a minimum application of silver solder, soldered the lot together:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6083.JPG)
That came out surprisingly well - even though it does not look like it.

That lot went into the pickle - I accidentally dropped it in from too far up and splashed some pickle out.  Fortunately that's no biggy, as I use citric acid for pickling (this batch is well-used already - hence the colour):
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6084.JPG)

While waiting for the pickle to do it's thing, I started on the valve handwheel from a bit of bronze:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6082.JPG)

Off to the mill and rotary table, and it was a quick job to drill some holes in it:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6085.JPG)

That was then taken back to the lathe, center drilled and threaded M3 to match the valve spindle, and parted off.  It's an "interesting" experience taking a parting cut through cross-drilled holes  :LittleDevil: .  To finish the parted side, I used the small lathe, as it's 3-jaw chuck with outside jaws were convenient for this step:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6086.JPG)

That left me with a functional handwheel:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6087.JPG)

The pack nut was also made from some 8mm hex brass, as well as the bit I stuffed up yesterday - those are visible next to the valve spindle in the above photo. 
The valve body came out of the pickle, and I did something I rarely do - gave myself a pat on the back - as the result is the best darn silver-soldering job I've ever done  :whoohoo: :
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6089.JPG)

I spent some time cleaning the bits up and took a family photo:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6090.JPG)

Then assembled the valve:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6091.JPG)
I'm rather pleased with that...

A shot of where it goes on the engine:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6092.JPG)

I'm struggling to find some suitable piping to make the final connections.  Everything I have in stock is either too thick or too thin.  The only supplier who has some suitable piping in stock had a computer outage when I was there and couldn't even give me a price; I'll try and get back there this week to see if they are back to business...
The final piping is needed, as I still have to drill a hole in the base for that and finish mounting the base feet.  I'd like to do that in one session though, as the base has it's final finish on it and I'm not keen on re-doing bits of that.
Then it's on to final assembly - finally!

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: Baron on July 06, 2014, 08:06:47 PM
Hi Arnold,


That valve has turned into a beautiful piece.  :cartwheel: :cartwheel: :cartwheel:   You should be justifiably pleased with it.  I know I would be.  :)

As far as soldering goes, I don't do much with silver braze.  I tend to used soft 60/40 and a hot air gun for small stuff.  One of the things that I'm playing about with is a speed controller for use with a 12 volt windscreen wiper motor.  I solder the power fet directly to the heatsink using the hot air gun.
Title: Re: Arnold's take on the MEM Corliss
Post by: Kim on July 07, 2014, 06:28:44 AM
That solder job looks great, Arnold!  Your valve turned out beautifully!
I'll give you a hearty pat on the back for that one too!   :ThumbsUp:
Kim
Title: Re: Arnold's take on the MEM Corliss
Post by: ths on July 07, 2014, 01:23:30 PM
Love the valve, as I do the rest of it. Hugh.
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on July 13, 2014, 06:12:16 PM
Thanks Baron, Kim & Hugh :)

Baron, I'd have used the electronics solder too, but didn't want to have the "grey" lines from that showing...  Ahhh - heat gun...  As a young lad I used to find old computer boards and desolder ICs from them in bunches - back then it was mostly 74-series TTL chips.  Never used it to solder circuits together though; it heats up the ICs and other components above specifications, so they're likely to be damaged.

I didn't get a chance through the week to get the piping, so thought I won't get around to much this weekend.  A neighbour popped in Saturday morning looking for an odd water pipe fitting (I'm known for hoarding all kinds of crap potentially useful items...  While digging through the boxes of pipe fittings, I came across an old geyser thermostat - with a length of just the right size brass tubing on it:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6107.JPG)

Right...  measured it up, and it was just over 5.5 mm OD - doesn't make sense in metric, but that rang a bell and turns out to be 7/32" in imperial.  This is thin-wall hard brass tubing, so bending it would be well nigh impossible.  That would require making some pipe fittings.

First up, a 90o elbow fitting was needed.
I turned up a brass "tube" from some 7mm stock, about 20mm long and drilled 5.6mm through for a relatively loose fit onto the tube:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6095.JPG)

To make the elbow, that bit of tube had to be cut through at 45o - but holding it without squashing it would be a problem.  So  I turned another section of 7mm brass down to a close fit on the inside:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6096.JPG)

The tube and "arbor" was then clamped up at 45o in the mill vise with a bit of cardstock positioned so that it would squash the tube onto the arbor and keep both secure:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6097.JPG)

I used a 1mm slitting saw to cut it - but before starting I thought things through carefully.  This wasn't exactly a very secure setup, and one concern was that the end of the arbor would be slit off - before the main workpiece was slit through.  So I had to keep a careful look-out for that and stop things the moment the arbor tip was slit off and remove that.  If left in the "tube" it could rotate, catch on the saw teeth and jam up or rip things apart.  So I started cutting, and as I approached that point, I slowed the feed down and kept a hand on the stop switch.  The moment the bit of arbor started to wiggle, I stopped the machine:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6098.JPG)

Then I used the hooked end of a scribe to pull the bit out:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6099.JPG)

After which I finished the cut:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6100.JPG)
The little "nub" left on the separated part was easy to file off afterwards with a fine file.

On to another brass fitting - one end of a bit of 10mm hex was turned down to 6mm and threaded M6 to fit the valve, and parted off about 15mm long.  Then it was screwed into an M6-tapped bit of brass held in the chuck, turned down to 7mm OD for a bit to match the "elbow-in-making", drilled 5.6mm to about 5mm deep to fit the tubing, and finally drilled through 4mm:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6101.JPG)

A short section of the brass pipe was cut off, and inserted and I checked the fittings together with the valve:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6102.JPG)

The section of pipe was still a bit long, so I shortened that by another 8mm.  After a final check, I made tiny scratches on the under-side of the screw fitting - to be out of sight, but give an indication of where the direction of the elbow must go.  To help keep things together for soldering, I flared the end sections of the piece of pipe slightly.  This was easily done by just squeezing a long-nosed pair of pliers into each end; the taper on the pliers deformed the ends just enough to make things tight, but leave room for flux and solder to wick through.  I silver-soldered the bits together - once again using a minimum of flux and silver solder.
Then I set up to solder the rest of the elbow and down-pipe on:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6103.JPG)


To measure where to drill the hole through the base, I moved the engine block to the side of the base, and took measurements from the mounting-hole locations:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6104.JPG)

After some more clean-up it looked OK and I left off there for Saturday:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6106.JPG)

Today I carried on with more bits of plumbing - the down-pipe was cut to length, and a ferrule and M6x0.5 threaded fitting turned up.  The ferrule will just be used to tidy up the hole in the base, as that needs to be slightly larger than the pipe to fit the 6mm threaded section through:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6109.JPG)

I used soft solder to solder the threaded fitting to the pipe - after first sliding the ferrule on to the pipe:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6110.JPG)
Soft solder's fine here; nobody will see the fitting.

Something not often seen... Tapping wood.  That's M8 to fit the ferrule:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6112.JPG)
This teak is darn hard, and felt like tapping brass - just easier.

What it looks like in position on the engine:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6113.JPG)

I spent some quality time starting to add finished bits to the engine block, as well as finally properly fitting the feet to the base:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6114.JPG)

Week evenings are a loss trying to get anything done; even if I do have a gap, it's too cold in the shop.  And I doubt I'll be able to do much next weekend; I'm booked for some major after-hours work at a client...

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: spuddevans on July 13, 2014, 06:55:52 PM
That is looking very fine :ThumbsUp: Arnold, and I like the way you fabricated the 90deg bend.

Tim
Title: Re: Arnold's take on the MEM Corliss
Post by: ths on July 14, 2014, 09:46:17 AM
Very nice soldering on the elbow, it can be risky silver soldering brass that thin. I'm always wary of the 'oops' moment when the brass flows better than the solder! Hugh.
Title: Re: Arnold's take on the MEM Corliss
Post by: Baron on July 14, 2014, 08:42:05 PM
Very very nice Arnold.  That is coming along a treat.

I agree with your comments about threading teak.  Its tough stuff !  The coffee table had a loose leg, one of those steel pressed in nuts with two spikes that stop it rotating.  So I turned the flats off an M8 nut.  I screwed it onto a M8 bolt and cut the outside M12.  Then I used a bottom tap to thread the hole in the leg M12.  I had to use a lock nut and a spanner to get the nut to screw into the wood.  It won't come loose again.
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on July 30, 2014, 08:16:48 PM
Thanks Tim, Hugh & Baron

Hugh, I used some of my lower temperature silver solder for that; it's still some of the "nasty" type with cadmium in it, but it flows at a lower temperature than the others I have.  To flow, it needs nowhere near brass's melting temperature; when the brass just starts to glow red, it works fine, and I used a normal plumber's torch to solder that.

Like mentioned in my last post, I haven't gotten around to much shop time of late - been busy with my day job basically day and night.  This past weekend was the coldest so far this year in our Winter, and I didn't go to the workshop either - stayed indoors and did trivial things, and slept a lot to catch up to lost sleep.  I'm on leave this week, and had been attending to other matters that got neglected in the last couple of months, but this morning I finally got back to the shop.

The engine was finally properly mounted to the base, and I made up another (crude) connector to fit the intake piping from the bottom:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6116.JPG)

I masked the blue paint on the flywheel, thoroughly cleaned the rim, and gave that a coating of clear lacquer - that should stop it rusting in future.

Then I started assembling the engine - giving each part a final finish as I assembled it.  A couple more studs were made to fit the valve to the top valve passage cover.  I'd never made a proper bolt for the valve rod pivot, so that was made, as well as a couple of spacers (not on the plans) for the crankshaft.  The one spacer fits between the main bearing support and the crank web, and the other between the eccentric and the main bearing support.  I took the length measurements for these spacers directly from the engine - and they will retain the crankshaft in the correct place:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6117.JPG)
 :facepalm2: I didn't take a photo of where the spacers are fitted - I'll do that later on.

I thought I was done making parts with the above lot, but during further assembly, I found I don't have enough of the turned-down 3mm washers I used for the rest of the engine to fit the outboard cylinder cover, and I need a final pipe fitting and a retainer for it.  Unfortunately, shop time came to a close; the doggies wanted their dinner, Shrek the parrot very loudly and repeatedly proclaimed from the living room "Ek wil 'n kasie he!" - meaning he wants a bit of cheese, and "Ek wil pappa toe kom" - meaning he want's to come to "daddy".
So I left the engine assembled as-is to attend to the zoo creatures.  All the preliminary timing is set on the engine; it now just needs the outboard cylinder cover fitted, a final air connection, and, after some valve adjustment the blind valve covers on the opposite side of the block.  I left it at this:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6118.JPG)

 :whoohoo: - tomorrow should be a great day in the shop  ;D

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: Roger B on July 30, 2014, 08:32:50 PM
Looking great  :praise2:  :praise2: Still following along  :ThumbsUp:  :ThumbsUp:
Title: Re: Arnold's take on the MEM Corliss
Post by: b.lindsey on July 30, 2014, 11:27:35 PM
Beautiful work on all counts Arnold. Love the feet, valve and just the WHOLE thing. Quite a showpiece you are making there!!

Bill
Title: Re: Arnold's take on the MEM Corliss
Post by: Don1966 on July 31, 2014, 12:16:26 AM
Arnold she sure is pretty! I have to say some nice work all around and my favorite color blue. Well a different shade but still blue. I like.......................... :praise2:

 :popcorn:

Don
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on July 31, 2014, 06:38:47 AM
Arnold, regarding those spacers you did on the crankshaft.

Without them, does the crankshaft move sideways during operation?  I thought that the connecting rod would hold the crankshaft in place but was not sure until you mentioned these spacers.

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: Baron on July 31, 2014, 08:01:34 PM

Hi Arnold,


Sorry I missed replying to your comment, I was so in awe of the pictures of your fine work.
Quote

Ahhh - heat gun...  As a young lad I used to find old computer boards and desolder ICs from them in bunches - back then it was mostly 74-series TTL chips.  Never used it to solder circuits together though; it heats up the ICs and other components above specifications, so they're likely to be damaged.


I agree with your comment about heating some components above spec, however there are a lot of IC's and power devices that are specifically intended to be soldered down.  Power FET's are just one example.  The idea is to use the PCB as the heatsink.  If you get chance to look at a modern computer main board you will see that the CPU power supply circuit regulator power devices are soldered to the board.


But yes I have done the same trick to salvage components from circuit boards.


 
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on August 01, 2014, 09:51:08 AM
Thanks Roger, Bill, Don, Vince & Baron  :)

Vince, it could run without the spacers, but I found it does wander a bit from side-to-side.  The cut-out in the base I made is very close-fitting; if the flywheel moves laterally by just one mm, the edges of the flywheel rubs against the cut-out. The spacers prevents this.

Well, I turned down some more washers and mounted the outboard cylinder cover, and made the last pipe fitting:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6119.JPG)

My preliminary valve settings appeared to be spot-on; when I installed the fitting and hooked the engine up to the compressor, it immediately took off.  The backward stroke was slightly weak, and by adjusting the intake valve closest to the flywheel side, that was soon gone.  The back end valve covers took a bit of time; I'd left them rough and had to finish them off before mounting.

...

...

Suddenly the engine was done.  It only hit me when I started looking around for a way to take a couple of photos.  Just over a year and a half went by since I started this build.  It's by far the biggest engine I've built to date, and yet includes some of the smallest parts and screw threads I've ever used.  The flywheel rim pushed my old ML7 to her absolute limits, and by choice I practiced some (bad) silver soldering to try and skill up on that.  There was a foray into wood-working for the base, with some accessories built for my router, as well as some tools built to make some jobs easier (ER11 indexer, lathe backstops).  It's also the first engine out of my twenty-odd where I focused on using stainless steel for fasteners, and mild steel rather than aluminium for bits that got painted.  Oh, and trying to do proper paintwork was part of the fun! 

Many Many Thanks to everyone who joined in with comments, suggestions, positive criticism and compliments during the build, as well as to those who just checked in and kept quiet  :praise2:

A LOT of Thanks must also go to the design team - there was a lot of discussion during the design, and Bob did a great job of drawing up and changing the plans based on the team's input.  Here's to the Lady and Gents involved in the design  :cheers:  - I can now vouch that the engine's a great runner.

Some photos:

(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6121.JPG)

(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6122.JPG)

(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6123.JPG)

(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6125.JPG)

(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6126.JPG)

(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6127.JPG)

(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6128.JPG)

(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6132.JPG)

(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6138.JPG)

(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6145.JPG)

(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6146.JPG)

Had to add something for scale - a wee dram o' single malt from the Highlands seemed appropriate  :) :
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6149.JPG)
 :facepalm2: There's ice in it...  :paranoia:


The obligatory video:
zhKA7ZdnF9s

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: Jo on August 01, 2014, 10:23:06 AM
 :pinkelephant:

Well done Arnold  8)

And well done Bob for putting together this design in the first place  :cheers:

Jo
Title: Re: Arnold's take on the MEM Corliss
Post by: Jasonb on August 01, 2014, 11:19:50 AM
Very nice model indeed and good to see it running at a sensible speed that allows all the works to be seen. :ThumbsUp:
Title: Re: Arnold's take on the MEM Corliss
Post by: tangler on August 01, 2014, 11:27:42 AM
Very nice   :ThumbsUp:

Thanks for sharing

Rod
Title: Re: Arnold's take on the MEM Corliss
Post by: Stuart on August 01, 2014, 12:42:31 PM
Very nice there Arnold


But I must chastise you the only thing you should add to a single malt is more single malt :cheers:


Stuart


Ps try some Glenfarclas 105 full cask strength
Title: Re: Arnold's take on the MEM Corliss
Post by: Ramon on August 01, 2014, 01:58:30 PM
Just caught up with the last few pages Arnold - very nice work on that lovely little valve to 'top out' a what has turned out to be a superb build  :praise2:.

Like Don I love the colour and she runs as good as she looks, everything must be just right to be able to turn over so slowly. An ace job all round :ThumbsUp:

That knock is not quite 'out of place' either  ;) - the Hick Hargreaves Corliss that runs at Forncett clicks and clacks to such an extent it can be heard wherever you are in the museum.

Really Nice Work

Ramon
Title: Re: Arnold's take on the MEM Corliss
Post by: Kim on August 01, 2014, 04:07:27 PM
Congratulations on a great runner Arnold!  :cartwheel:  You've done a suburb job on the corliss and it shows. :ThumbsUp: :ThumbsUp:
Thanks for sharing the video and your whole build process with us!
Kim
Title: Re: Arnold's take on the MEM Corliss
Post by: vcutajar on August 01, 2014, 04:15:13 PM
My hat is off to you Arnold.  Gorgeous model and a detailed build log which helped quite a bit.  Can't wait to finish mine and try to have something similar.

Vince
Title: Re: Arnold's take on the MEM Corliss
Post by: sbwhart on August 01, 2014, 04:39:50 PM
That is nice  :cartwheel: great job Arnold


Stew
Title: Re: Arnold's take on the MEM Corliss
Post by: smfr on August 01, 2014, 05:15:37 PM
 :whoohoo: Excellent! That's a fine engine, Arnold!  :ThumbsUp: :ThumbsUp:

Simon
Title: Re: Arnold's take on the MEM Corliss
Post by: RMO on August 01, 2014, 06:06:40 PM
Inspiring!  Now I want to build one.  Maybe in the winter when the shop is not full of VW engines for other folks.

Mike
Title: Re: Arnold's take on the MEM Corliss
Post by: Alan Haisley on August 01, 2014, 06:30:28 PM
Now, THAT'S an engine  :praise2:

Alan
Title: Re: Arnold's take on the MEM Corliss
Post by: mklotz on August 01, 2014, 06:36:14 PM
Absolutely beautiful work, Arnold.  Be proud of yourself, very proud.
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on August 01, 2014, 06:46:27 PM
Many thanks for the kind words All  :)

Stuart, I'll be on the lookout for Glenfarclas - the selection in stores over here is rather limited, but I might just find it somewhere.

Ramon, if the "real thing" clicks and clacks, I'm not going to worry any further about it :)

Vince, I'm sure yours will turn out even better looking with the additional details you're adding, and just as well-running  :ThumbsUp:

Mike, go for it; it's a fun build - and need not take near as long as I've been about it.


Well, she found her spot in the living room - there's not enough space with the other engines, so she got her own one:
(http://www.nam-engineering.com/cm/albums/userpics/10004/normal_IMG_6160.JPG)

I'll need to get a bigger table mat though; that one's a bit small.

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: Tennessee Whiskey on August 01, 2014, 06:51:23 PM
Arnold, from one Southerner to another that's way South, a truly beautiful job. I enjoyed the build as it progressed and this morning glanced back thru the whole thing again and it's just a great job all around :cheers:. I think a nice tanned hide would be great for a table mat

Whiskey
Title: Re: Arnold's take on the MEM Corliss
Post by: b.lindsey on August 01, 2014, 07:00:37 PM
Totally awesome Arnold!!  What a gorgeous engine, thanks for taking us along on the journey!!

Bill
Title: Re: Arnold's take on the MEM Corliss
Post by: rarach22 on August 01, 2014, 07:04:42 PM
beautiful work, thank you for the photos and video
Title: Re: Arnold's take on the MEM Corliss
Post by: Roger B on August 01, 2014, 07:12:16 PM
That is magnificent  :praise2:  :praise2: As I have said before I do enjoy watching steam engine valve gear although I don't fully understand it  ::)  :ThumbsUp:  :ThumbsUp:
Title: Re: Arnold's take on the MEM Corliss
Post by: fumopuc on August 01, 2014, 07:32:43 PM
Hi Arnold, first of all thank you very much for investing the time and sharing this build log with us. A beautiful engine and a perfect runner is the  final result. Very well done. And, as  already mentioned before, thanks to the  MEM team and Bob for sharing the drawings with all of us. Arnold, may be one day, this engine will get a governor and a adjustable steering of the inlet timing. Nicely done  video, also.
Title: Re: Arnold's take on the MEM Corliss
Post by: tvoght on August 01, 2014, 08:24:54 PM
Very fine. The first MEM Corliss off the line if I'm not mistaken, and in MEM logo colors.
The low-speed performance is surely a testament to your craftsmanship.

--Tim
Title: Re: Arnold's take on the MEM Corliss
Post by: spuddevans on August 01, 2014, 08:53:04 PM
That is a beautiful model Arnold  :ThumbsUp: :ThumbsUp: :ThumbsUp: Well done  :jumpingsmileys:

Tim
Title: Re: Arnold's take on the MEM Corliss
Post by: zeeprogrammer on August 01, 2014, 10:48:27 PM
Stunning model Arnold. Just stunning. The slow speed was awesome.

Sorry I haven't been around much. Doesn't look like things will change much either.

The obligatory video:

Are not 'happy dances' obligatory?
Title: Re: Arnold's take on the MEM Corliss
Post by: Stilldrillin on August 01, 2014, 10:52:10 PM
A superb climax, to a very entertaining build, Arnold.   :praise2:

Thank you, for taking us along with you........  :)

David D
Title: Re: Arnold's take on the MEM Corliss
Post by: b.lindsey on August 02, 2014, 12:44:38 AM
"Are not 'happy dances' obligatory?"


You set the bar too high Carl, we are mere mortals in the Happy Dance category :)

 Bill
Title: Re: Arnold's take on the MEM Corliss
Post by: Maryak on August 02, 2014, 04:41:12 AM
Hi Arnold,

That is simply the Ants Pants, Bloody Brilliant, Magnificent, etc............................Don't you just love it when a plan comes together. :ThumbsUp: :ThumbsUp: :ThumbsUp: :cheers:

Thank you for the honourable mention. I know you built it................. but I sorta, kinda feel part of the process and it's a very nice feeling let me tell you.

Best Regards
Bob
Title: Re: Arnold's take on the MEM Corliss
Post by: Baron on August 02, 2014, 01:50:15 PM
Hi Arnold,


Well, what can I say !  :praise2: :praise2: :praise2:


Everybody has said it all.  It looks really good, it sounds very nice, its almost a shame that it isn't in an exhibition somewhere, where more people could appreciate the beauty of a superb engine build.  :cheers:





Title: Re: Arnold's take on the MEM Corliss
Post by: pgp001 on August 02, 2014, 03:26:27 PM
Arnold

You have made a smashing job of that engine, it looks really good.
I feel guilty mentioning this, but to my mind it is running backwards, I am used to seeing mill engines run the opposite way especially when the crosshead runs on slides.
Yours being a trunk guide does not matter as much, so is not wrong.

Phil
Title: Re: Arnold's take on the MEM Corliss
Post by: Don1966 on August 02, 2014, 04:45:34 PM
Arnold I must sing like the rest and that's an absolute beauty and what a runner that slow speed is awesome. That engine is differently on my list to build and the color. I like........................ :praise2:

Don
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on August 02, 2014, 06:15:00 PM
Once again, many thanks for the kind words All  :praise2:

Whiskey, I think I'll skip the hide; there's enough on the two Okavango drums beside the trolley the engine is on, and that's enough for me  ;)   

Achim, yes; it will get the governor and trips one day; I first wanted to finish it to "basic" level.  I'll get back to the governor after about two other engine and some tooling builds  :ThumbsUp:

Carl, you must know by now I'm no darn good at dancing  :-[ .  No need to be sorry about not being around much; I know exactly what you're talking about; haven't been a shining example myself of late...

Bob, I'm really really glad you feel a part of the process - like you say, I may have built it, but it's the team's engine  :ThumbsUp:

Phil, no need to feel guilty about commenting on running directions and so on; I've never in my life seen a real mill type engine in operation, so have no clue about that.  That's another tidbit of information added to my "books" - and when I build the governor and trips, I'll turn the eccentric through 180o to make it run more true to life  :)   

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: pgp001 on August 02, 2014, 07:04:00 PM
Arnold

The reason a "typical" mill engine goes the other way is so that the load on the crosshead slide always bears "downwards" onto the bed of the engine on each power stroke.

Not a big deal, but just thought you might be interested to know why.

Phil
Title: Re: Arnold's take on the MEM Corliss
Post by: ReFlad on August 04, 2014, 03:16:36 PM
Just Awesome, Arnold.  What a very nice build and sweet runner.  Your talents are inspiring!  Great Job!

Ronald
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on August 04, 2014, 10:12:15 PM
Thanks Phil - I thought things through and that makes perfect sense  :NotWorthy:    I'm curious now - were there engines built with just a bottom slide for the crosshead, i.e. no slide/containment at the top?  I'm thinking sort of like a Myford lathe's ways as the crosshead guide and the apron being the crosshead.  Under full engine power the crosshead, combined with its weight, would bear down from the top, and in rare circumstances where there would be no load on the flywheel, and the engine steam supply got cut, possibly creating a vacuum in the cylinder, the under-side of the slides and a wrap-around on the crosshead would keep it from lifting off... 

Thank you very much Ronald  :NotWorthy:

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: Jasonb on August 04, 2014, 10:18:27 PM
Plenty like that, usually had a rebated bar to stop the cross head lifting.

http://prestonservices.co.uk/item/single-cylinder-horizontal-workshop-engine-3-x-3-34-cylinder/
Title: Re: Arnold's take on the MEM Corliss
Post by: Jo on August 05, 2014, 06:06:53 AM
That is  the same as on my Corliss Cross Compound  ;).

Jo
Title: Re: Arnold's take on the MEM Corliss
Post by: pgp001 on August 05, 2014, 01:03:20 PM
And "Agnes"

(http://i456.photobucket.com/albums/qq286/pgp001/Model%20Engineering/Pollit%20and%20Wigzell%20Mill%20Engine%20%20Agnes/At%20Markham%20Grange/Agnes151_zps8f8be645.jpg) (http://s456.photobucket.com/user/pgp001/media/Model%20Engineering/Pollit%20and%20Wigzell%20Mill%20Engine%20%20Agnes/At%20Markham%20Grange/Agnes151_zps8f8be645.jpg.html)

Phil
Title: Re: Arnold's take on the MEM Corliss
Post by: kvom on August 05, 2014, 02:34:28 PM
I'll add my voice to the praise chorus.  Superb!   :cheers:
Title: Re: Arnold's take on the MEM Corliss
Post by: ths on August 06, 2014, 10:16:01 AM
I'm a bit late Arnold, but congratulations, that is a superb bit of work. I'm a Laphroaig man myself, and I'll have one for you. Best wishes, Hugh.
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on August 06, 2014, 06:42:04 PM
Thank you for the compliments kvom and Hugh  :)

Thanks for the information Jason, Jo & Phil.  Hmmm...  The engine Jason linked to looks like a nice candidate to build a smaller barstock model of - say 1/3d or 1/4 scale...  :thinking: - Or a modified version of Elmer's #41 Factory Engine or #33 Mill Engine...  Rats...  Now that lot is in conflict with an attempt at a simple Ruth's Rotary, a mad-cap six-cylinder-many-gear-radial-just-for-fun compressed air engine, and a simplified live-steam version of a vertical portable steam engine from a "local" (900 km round-trip) museum...

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: NickG on August 18, 2014, 08:03:00 PM
Brilliant Arnold, fitting first version of MEM's own engine. Quite a feat by all involved I think, well done.
Title: Re: Arnold's take on the MEM Corliss
Post by: fcheslop on August 18, 2014, 09:08:00 PM
Thanks for taking the time to do the post Arnold
She is truly stunning :praise2: :praise2:
cheers
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on August 31, 2014, 02:30:14 PM
Thank you Nick & Frazer  :)

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: HobbyNut on September 01, 2014, 05:54:39 AM
Well done, beautiful runner, and thanks for all the documentation. :ThumbsUp:
Title: Re: Arnold's take on the MEM Corliss
Post by: Nicolas on September 01, 2014, 07:44:55 AM
Fantastic work Arnold :praise2: :praise2: it looks great and it runs great :ThumbsUp: :ThumbsUp:

I haven't had the time to have a proper read through the build, will do that after exams when I get my free time back :)

Are you still planning on building Elmer's #5 as your next one?

Nicolas

Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on September 01, 2014, 10:48:04 PM
Thank you Pat & Nicolas  :)

Nicolas, you might be happy to know that the plans for the #5 is printed, mostly converted to metric, and that I've pretty much run the machining steps for the gears through my mind...  So stay tuned  ;)

Kind regards, Arnold
Title: Re: Arnold's take on the MEM Corliss
Post by: Nicolas on September 02, 2014, 02:31:02 AM

Nicolas, you might be happy to know that the plans for the #5 is printed, mostly converted to metric, and that I've pretty much run the machining steps for the gears through my mind...  So stay tuned  ;)


I look forward to seeing your build and learning some new techniques and ideas ;) knowing you, I won't have to wait very long for you to make a start (and finish) :Lol: :Lol: :Lol:

Nicolas
Title: Re: Arnold's take on the MEM Corliss
Post by: gbritnell on September 02, 2014, 03:26:11 AM
Hi Arnold,
I'm sorry for being so late to comment but you have done a fantastic job on your engine. I know what it takes to document a long build like this so my appreciation is doubled. I have a beam engine that will knock with just the slightest looseness in the crank pin so I wouldn't be too concerned about it.
gbritnell
Title: Re: Arnold's take on the MEM Corliss
Post by: Alan Haisley on September 02, 2014, 04:49:29 PM
Thank you Pat & Nicolas  :)

Nicolas, you might be happy to know that the plans for the #5 is printed, mostly converted to metric, and that I've pretty much run the machining steps for the gears through my mind...  So stay tuned  ;)

Kind regards, Arnold
Looking forward to some gear making  :P
Title: Re: Arnold's take on the MEM Corliss
Post by: philjoe5 on October 12, 2014, 03:24:14 PM
Hi Arnold,
Just found this build log.  Your engine is beautiful and an inspiration. :ThumbsUp:

Cheers,
Phil
Title: Re: Arnold's take on the MEM Corliss
Post by: arnoldb on October 12, 2014, 11:06:42 PM
Thank you George, Alan and Phil  :praise2:   - and apologies for the late reply.

Kind regards, Arnold