Model Engine Maker

Engines => From Kits/Castings => Topic started by: scc on September 27, 2021, 07:10:05 PM

Title: Murdoch-Aitken "Steeple" engine
Post by: scc on September 27, 2021, 07:10:05 PM
Just a quick intro to my next project.  A new venture for me.......castings!      My Burrell used lots of them but they were big and easy to hold. It is a good job that I have been following Jo's excellent tutorials.      I have a few tidying jobs in the shop first and then off we go.       Terry



Edited by Jo: Corrected Title Spelling  ::)
Title: Re: Mudock-Aitken "Steeple" engine
Post by: Dave Otto on September 27, 2021, 07:14:24 PM
Hi Terry

I will be pulling up a chair and following along.

Dave
Title: Re: Mudock-Aitken "Steeple" engine
Post by: Don1966 on September 27, 2021, 09:19:53 PM
Yep Ike Dave I will be following you also Terry!…..


 :popcornsmall:
Don


Title: Re: Mudock-Aitken "Steeple" engine
Post by: Jo on September 27, 2021, 09:29:35 PM
 8) Nice one Terry,

Looking through my notes on this engine I found something that claims there may be a couple of drawing corrections:

The engine has two side rods connected by a bridle beneath the table. From here, a single short connecting rod goes down to the big end. As drawn, the bridle would have struck the top of the crankshaft bearing. I had to lengthen the short rod, and shorten the side rods by about a quarter of an inch. This now meant that the bridle hit the underside of the the table. The table top was duly excavated to make room. Actually, this no bad thing, as the table tops on full size table engines were assemble from five castings, and were in fact hollow.

The side rods, as drawn, would not pass the exhaust belt, of through the slots either side of the cylinder top. I kept the "fish bellied" profile, but filed flats on each side to give clearance. It sounds like a bodge, but in fact it looks quite good, and I have seen something like it in full size, just for the decorative effect.

The positioning of the little brackets that carry the shaft drive for the governor is a bit vague. In the end, I fixed mine to the foundation block, not the engine bed plate.

The starting levers are quite unlike the original drawings. With the levers in front of you, the left hand one, which disconnects the valve gear from the eccentric, is connected to the eccentric rod buy a parallelogram of levers. Lift the lever, and the slide valve is free to be moved. The right hand lever is to do the moving. It is held in the valve shaft by a taper, and could be removed for safety once the engine had started. If the parallelogram of levers, previously mentioned, are correctly proportioned, then the left hand lever does not move when the engine is in motion. I found this quite a surprise, but it means that it does not present a hazard.



Best to be aware of them before you start  ::) and I have attached some picture of the original engraving of this engine

Jo

Title: Re: Mudock-Aitken "Steeple" engine
Post by: scc on September 30, 2021, 08:06:56 PM
Glad to have you following along Dave and Don, but don't expect rapid progress!   This is very new teritory for me.....small and fiddly, The drawing even shows some 14ba bolts :o
Jo, Thank You for your detailed  response.  Valueable info indeed. I'd heard rumours of drawing errors.  Those etchings are great and make the drawings much easier to follow, I have printed them off for the workshop wall and inspiration :facepalm2:

Thanks again      Terry
Title: Re: Mudock-Aitken "Steeple" engine
Post by: Jo on October 05, 2021, 03:02:20 PM
This is very new teritory for me.....small and fiddly, The drawing even shows some 14ba bolts :o

:headscratch: I found a few 12BA but not 14's. If you don't like 14BA then 1mm might be easier to come by.

 I keep wanting to make my one of these ... you have got me tempted  :thinking:.

Jo
Title: Re: Mudock-Aitken "Steeple" engine
Post by: AVTUR on October 08, 2021, 11:01:58 AM
Terry

How large is this engine? The diameter of the flywheel would be useful.

I will follow, every so often, with interest.

AVTUR

Title: Re: Mudock-Aitken "Steeple" engine
Post by: scc on October 08, 2021, 08:57:20 PM
Jo, it would be good if you made one.......I could follow along and see how it's done :Lol:     None of my usual suppliers even list 14ba, 12 being their usual limit.

 Avtur,  welcome along,  I think the flywheel is about 9 1/2 inches dia.      Terry
Title: Re: Mudock-Aitken "Steeple" engine
Post by: scc on October 08, 2021, 09:01:49 PM
OH DEAR,     I have just noticed that I spelt the title completely incorrectly :embarassed: :embarassed:     It should read "MURDOCH"

Apologies           Terry
Title: Re: Murdock-Aitken "Steeple" engine
Post by: Jo on October 08, 2021, 10:28:02 PM
OH DEAR,     I have just noticed that I spelt the title completely incorrectly :embarassed: :embarassed:     It should read "MURDOCH"

All sorted  ;)

Jo
Title: Re: Murdock-Aitken "Steeple" engine
Post by: crueby on October 08, 2021, 10:42:49 PM
OH DEAR,     I have just noticed that I spelt the title completely incorrectly :embarassed: :embarassed:     It should read "MURDOCH"

All sorted  ;)

Jo
Almost, the R is now there, but the K at the end should be an H?
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Jo on October 09, 2021, 07:36:44 AM
 :facepalm: Done that as well.

I have just found someone admiring his set of these castings.  :thinking: He claims it takes up a large amount of his Casting cupboard relative to what it is. I am increasingly becoming concerned about the amount of space required in the house for all the finished model engines and this one is not small  :o

Jo

Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Jasonb on October 09, 2021, 07:42:16 AM
Probably need to update cache as it's right in the headings down the left of page only K in the thread.

14BA are not that easily found at least if you want them in steel, I cad a quick look over the drawings and could not easily spot them so assume there ate only a few required in which case you may be better off making yourself.

Out of interest what is the date of your drawings, it could be now that Blackgates are doing the castings there have been some changes possibly as 12ba was a bit tight in places. Also awaiting to hear what the castings machine like as the old Clarkson ones had a reputation for being a bit chilled particularly the two tal thin crosshead guides, hopefully the Blackgates ones will be OK.

Overall height is about 18"
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Jo on October 09, 2021, 08:03:36 AM
These are an original Clarkson  :facepalm2:  set, with the Drawings dated 1971.

Jo
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: ettingtonliam on October 09, 2021, 08:54:20 AM
I first fell in love with this engine back around 1968, and had a Clarkson GA of it for many years. As with so many things, it never happened, and by the time I was in a position to build one, Clarksons had long gone. When I heard that Blackgates were supplying now, my interest was reawakened, but you lot have put me right off. All this talk of 14BA and 12BA screws! I've long had a personal rule - nothing smaller than 6BA, indeed 5BA for preference.
I shall read the build logs with interest though.
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Jo on October 09, 2021, 12:06:15 PM
I am not worried about the small stuff. It looks like they can all be done by through holes and bolts if you want (I will be studding)  :)

Jo
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Jo on October 09, 2021, 04:12:45 PM
I have just found a picture of the original model from 1932 (attached). Clarkson's purchased the rights to market the model  ;)

Jo
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on October 11, 2021, 07:39:43 PM
Thank you Jo for the spelling correction(s)               Well I have made a start by squaring up the bedplate casting to provide a datum.  As you can see in the second photo the endmiil decided to drop out of the collet :facepalm:  Never happened on barstock of course,  only on a one off casting.....JB required.    I drilled and tapped the four main holes and screwed on two bits of scrap to enable a good hold on the mill.  I don't think the whole top surface needed machining, just the column and bearing mounting  cutterpoints.  However I followed the drawing and brought it all down to thickness.  Jo, I agree with the through holes but I think I too will use studs. I'm undecided on the wedges as I will have to buy a dovetail cutter >:(
Jason,   the only hard stuff on this first casting was the edges of the flash which would not file off. needed a touch with the Dremel. 
Casting age is unknown but puchased last year.  The pair of upright crosshead guides are brand new,recently supplied by Blackgates following a broken pattern.       My drawing set is 1971/2                 Terry
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Jo on October 11, 2021, 09:38:25 PM
Good start  :)

I cannot remember if I ever used a dovetail cutter on these  :thinking: It’s easy enough to make a cutter for the cotters/wedge slots ;)

Jo
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Jasonb on October 12, 2021, 07:06:26 AM
Yes a small flycutter type single point tool would do those undercuts for the wedges. Or as they are unlikely to really do anything you could make dummy wedges with a section of dovetail at the end and just parallel so it can be dropped into place.

Full size would only have machined the pads but sometimes if a model casting is a bit variable your method to do it all will tidy things up.
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on October 12, 2021, 08:22:01 PM
Interesting to see the original casting set Jo. There are a couple of small differences to mine. It looks as though the main bearing caps used a different pattern, My set has a much smaller length of gunmetal for the bearings, and you have a set of bevel gears for the governer.  I was amazed to see how tall my main bearing castings are..it would do caps as well!
I admit gunmetel is a "new" material for me :-[.........anything I should know?             Terry
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Jasonb on October 12, 2021, 08:39:40 PM
It's interesting that neither set of castings seem to be the correct shape to suit the drawings which show a profile like I have shown in green which is what is also shown on those images of the full size one and the 1932 model. Did Clarkson purchase the drawings and then make up their own simplified castings?

Gunmetal can be soft so take care when holding in teh chuck etc that you don't make finished surfaces but does depend on the actual alloy.
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Jo on October 12, 2021, 09:33:17 PM
I was planning on making Jason’s day and making replacement main bearings  out of bar stock :-X The trick to getting the correct profile is to take a bigger piece of steel. Drill two holes the diameter of the half round profile at the correct centre distance, mill these to half width then silver solder in two pieces of rod.

As Jason has said some of the castings look like they were not originally castings and clarkson made patterns for them.

Mine also came without the gears but then I got lucky and I acquired that set with another partial set of clarkson castings that had gears with it and knew that they were not for that engine and got lucky  ;D

Jo
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Craig DeShong on October 12, 2021, 09:47:36 PM
The terminology “steeple” has me a bit confused.  My only reference is to a “steeple quad” engine that was installed in a steam driven tugboat.  Obviously this engine is quite different.


Trying to remember the specifics of the “steeple quad” I refer too; I believe it was a triple expansion engine with the cylinders stacked on top of each other, with the two low pressure cylinders occupying the base.

I was planning on researching this engine for a possible build, but I forgot all about it.  I’ll need to keep this idea in my back pocket.

Though the engine of this thread is obviously not the one I was thinking of, it certainly does look interesting.  I’ll need to follow along with this build.
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Jasonb on October 13, 2021, 07:18:57 AM
Yes there is always scope to add your own touches as the castings if you wish which may have been "adjusted" to suit production methods or the original details were not present. Soldering up as Jo mentions is probably the easiest though you can cut the profile from a block of cast iron if you want to stick as close as possible to a casting set. Might even be possible to cut off the foot and use the castings you have got then join on a separate foot once the profile is cut with a couple of CSK screws from below with a tough of JBWeld.

(https://hosting.photobucket.com/images/v156/jasonballamy/Tid30.JPG)

Also possible to save metal by drilling half a hole down the side of the block rather than a hole and milling some away, trick is to clamp both bearings together so you end up with half a hole in each and drill goes straight down.

(https://hosting.photobucket.com/albums/v156/jasonballamy/Engineering/EastonandAnderson/.highres/IMAG0995.jpg)

Cutting from solid, I used the DRO but two passes with a roundover cutter may also work.

(https://hosting.photobucket.com/albums/v156/jasonballamy/Engineering/EastonandAnderson/.highres/IMAG0787.jpg)

(https://hosting.photobucket.com/albums/v156/jasonballamy/Engineering/EastonandAnderson/.highres/IMAG0789.jpg)

Talking of feet on the bearings the note under the description says 5/32" packing and drawing shows 3/16. Should be whatever the thickness of your now machined casting is (3/16") if main foundation is to be the same height as outrigger foundation
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Jo on October 13, 2021, 07:42:22 AM
The terminology “steeple” has me a bit confused.  My only reference is to a “steeple quad” engine that was installed in a steam driven tugboat.  Obviously this engine is quite different.

You are right Craig, this is a Table engine not a Steeple - which has the cylinder on the floor and all the mechanism above it. For some reason Clarksons called it their "Steeple" engine and the name stuck.

If you look at the original 1932 photo you will see it called a Table Engine  :).

Jo

Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Jo on October 13, 2021, 08:46:00 AM
I might have found a missing bit  :noidea:. I cannot seem to find this bearing stand anywhere on the drawings.

Jo
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Jasonb on October 13, 2021, 01:04:03 PM
It's those dodgy metric drawings of yours :LittleDevil:

Also the source of the 14BA fixings ;)
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Jo on October 13, 2021, 01:36:12 PM
I have got to the source of the problem: I have two different sets of Clarkson Drawings  :ShakeHead:. The original Blue prints show the bracket. The normally printed ones do not and they have duplicated some of the valve gear parts (slightly differently).

I also noted that the main bearing was taller on one set of drawings. I need to go through these with a fine  :wine1: and see if I can find any more variations.

Jo
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on October 13, 2021, 09:55:40 PM
Thanks folks for your inputs.   It looks as though some calculations will be needed to ensure it all fits together before cutting metal.    I wonder if Craig's "steeple" engine was one of these? a Willans   triple expansion stacked up and looking church steeple like. All three pistons fixed to a hollow piston rod and the piston valves within :o can rev   to 500rpm.  I don't think it would make a good model as all the moving bits are enclosed.               Photo from George Watkins book    "the stationary steam engine"               Terry
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: derekwarner on October 14, 2021, 02:58:23 AM
There you go....open the image & it is a vertical engine  :wine1: ...I do not understand why the thumbnail persists to be on it's side  :killcomputer:

Is this a twin cylinder steam engine driving a DC generator?
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Jasonb on October 14, 2021, 07:03:32 AM
Bit more than a twin, I suppose you might call it a twin triple tandem compound as it has two sets of triple compound cylinders in a tandem (axial) alinement so six cylinders in total
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on October 23, 2021, 06:54:08 PM
Made a start on the columns, set up in the 4jaw on the  little Clarke, machined all the round bits and finished the ends to length. I had already marked out and centre drilled the small ends. There was a chucking spigot on the large end.......took a load of photos and tried to upload last night :headscratch:     Earlier I had removed the camera battery to recharge forgetting that when battery is replaced everything reverts to original settings which are not pc friendly :cussing:      so no pics.   I milled the ends to size today as seen in these new pics. Simply set the cutter to centre level then drop the table half the dimension required. Both ends now done.  I was surprised by the amount of metal that needed removal, but the castings machined very well. I shall leave the flutes as they are...maybe a little smoothing.          Terry
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Admiral_dk on October 23, 2021, 07:53:34 PM
Shame about the camera - but at least you got shoptime  :ThumbsUp:
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Kim on October 23, 2021, 11:29:07 PM
Well, the columns as you show them now look great!  I'm sorry we didn't get to see the other work on this though.

There is often tools you can use on a PC to convert the raw images from a camera to JPG.  What format does your camera store pics in by default?  If it's just a size thing then there are definitely many tools available to re-size (that is, if you're interested anyway :)).

Kim

Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on October 24, 2021, 09:17:35 PM
Cheers Folk!    Found the  flatest surface and cleaned up with a light milling. I then turned it over to mill the base. This and the top flange both need a lot of thinning to get the piece to final size. The top will need a small end mill to navigate round all the "lumps", not looking forward to that stage.          Terry
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Jo on October 25, 2021, 07:44:42 AM
Morning Terry, you are making good progress on your "Steeple"  :).

I don't normally use a milling cutter to clean up castings. Just hand files, a Dremel and sometimes my old hand engraver to encourage bits out of the corners ;)

Jo
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Jasonb on October 25, 2021, 08:13:15 AM
I was about to say similar. Unless the casting is very over size I would have expected the machining to be minimal only needing to flatten the bottom so it sits well on the columns and then on the top just the central pad for the cylinder and the two for the crosshead guides (steeples) and probably a spot face for the 4 nuts

Or are you just thinking of taking a pass around the outside of the flanges to straighten them out as shown in green in which case you can just file the internal corners square rather than use small cutters
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on October 25, 2021, 08:25:03 PM
I would agree   but....... The dimension from the bottom face (top of columns) to the mounting face for the crosshead guides is shown as 0.75"
I have already machined the bottom face as much as I dare.....0.072"thick on the flange. When I measure from this face to the top I get 0.855".
If I then remove the 0.105" reqd the top flange will be too thin. :shrug:  It may be possible to further reduce the bottom flange AND modify the bottom of the crosshed guides :thinking:  otherwise some adjustment of upper dimensions will be required.           Terry
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Jasonb on October 25, 2021, 08:38:23 PM
I see what you are dealing with now. Another option would be to clean up the cross head mounting pads and then turn it over and machine the bottom flange right off to give a thickness of 0.688" and then add a new flange from 1/16" thick material. This may well be quicker and easier than trying to mill all round the top features and still end up with a thin top flange.

Interesting to look at the general arrangement drawing which seems to shows a narrower portion below the bottom flange. But then again that also shows the usual 24 flutes to the columns so don't know how well that relates to what you actually get.

What does your casting look like it will machine to Jo? assuming you are allowed to touch it.
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Jo on October 25, 2021, 09:05:06 PM
I'd leave it where it is Terry.

If you recall there are some known "features" on this engine one of which is the crank hits the bottom of that plate and it is suggested we grind a bit underneath so it clears so a bit more space is worth keeping for now   :)

Write yourself a note and keep it with it (or on it) to remind you that it is over thick and by how much ;)

Jo
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on October 25, 2021, 09:52:34 PM
I  think I will go with that Jo :ThumbsUp:   Terry
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Jo on October 25, 2021, 09:56:49 PM
I was just allowed another look at the casting  ::)

The key distance is from where the cylinder sits to the bottom of the cross head guide. It looks like you just need to make the top flat where the cross head guide goes so it is at the same height as the outer surface of the layer you were measuring to and then take the top surface down so it is the required 7.14mm up. There looks to be a couple of mm spare  :)

Jo
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Jasonb on October 26, 2021, 07:11:52 AM
You would probably want to check that the cross head does not bottom out in the slot if making the distance from crankshaft to guides plus 0.105", or at the very least does run equally to each end.  This would also affect eccentric rod length, overall height of governor assembly, etc as you are changing the height above the base for the shaft and bracket mounting. Also if cylinder is sitting higher up you will want to look at piston rod length so you don't hit a cylinder cover.

Would be worth drawing out the basic overall heights of the parts and checking for clearances etc at TDC and BDC so it does not come back to bit you at a later stage. If you only have pencil and paper then make the conrod assembly from a separate bit of card so you can try it at different positions over the main drawing, ditto eccentric rod.
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on October 26, 2021, 01:27:07 PM
Thanks people :cheers:   Terry
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on October 31, 2021, 08:55:26 PM
Recent activity has been to level the bases for the crosshead guides and machine to width, carefully working from a centre line.   I could not resist resting the bits in place .      Terry
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: crueby on October 31, 2021, 09:40:13 PM
What a fine looking engine that will be!    :popcorn: :popcorn: :popcorn:
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on November 07, 2021, 07:49:02 PM
An update........In view of my basic marking-out equipment, ageing eyesight, etc. I have made a drilling guide for the 10ba fixings at the base of the crosshead guides. The chance of "spotting-thro" is minimal and I need things to line up. The holes were drilled using the dials on the mill rather than measuring. The the jig was carefully lined up and holes drilled (tapping size)   When the frames are done the same jig will be used.           

I suspect that little shop time will occur for the rest of the year :( My wife's business has already become manic in the run-up to Christmas,    taking most of my home time.             Terry
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Jo on November 07, 2021, 07:54:06 PM
Drilling jigs are a reliable way of achieving lined up holes  :ThumbsUp:  It is worth marking them so you know which way round they go   ::)

Jo
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on November 07, 2021, 09:14:08 PM
I did stamp it Jo, after the photo......R, L, UP :)    Terry
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: GWRdriver on November 07, 2021, 10:16:25 PM
If you recall there are some known "features" on this engine one of which is the crank hits the bottom of that plate - Jo
Has a compilation of these special "features" been collected by anyone, such as Alan Stepney did once upon a time?
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Double Dutch on November 30, 2021, 02:52:41 PM
Hello,
I am new to this forum.
I have a set of Murdoch & Aitken castings in stock as the next project after I finished my Stuart No1.
One problem of the casting is the hardness of the thinner parts.
I have annealed some castings in the past, but I am not sure if I used the correct procedure.
Does anyone has experience in annealing castings?
I used a temperature of 700drgC and a cooldown gradient of 50drgC an hour.
If anyone has correct figures I will be very please before I spoil my castings.

With kind regards,
Double Dutch

Learn from other men’s mistakes, you will never get old enough to make them all by yourself.
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Jasonb on November 30, 2021, 03:04:36 PM
DD, Have a look at this recent post, you want teh temp a bit higher.

https://www.modelenginemaker.com/index.php/topic,10596.0.html
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: ettingtonliam on November 30, 2021, 10:43:21 PM
Put them in the fire at the end of the evening, covering them up with glowing embers. Go to bed. When you rake out the fire in the morning, they will be annealed.
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on December 01, 2021, 09:27:21 PM
I wish :disappointed:   Our house is in a Conservation Area with a smokeless zone so  NO fires :Mad:  Our previous house (33yrs ago) had a Rayburn which would have been ideal.   Progress?   Terry
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Double Dutch on December 05, 2021, 02:29:54 PM
Hello
I had just contact with Graham from the Alyn Foundry.
He advices to heat up a little above 750dgrC and let it cool down as slow as possible
Our chemical department at work has a large oven which easily reaches 1500dgrC.
I will keep you updated.
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Dave Otto on December 05, 2021, 05:01:15 PM
Did you look at the link Jason posted above? 750 might be a bit low.

Dave
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Double Dutch on December 08, 2021, 09:54:20 AM
I found an article about the Murdorch and Aitken from ME Juli 1979
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on December 11, 2021, 07:33:27 PM
Thank you,    Double Dutch,   an interesting article but does nothing for my confidence :o     My wife's business has gone much quieter since this latest Covid development so I have been able to escape to the shed albeit briefly.   I had a bit of a tidy up of the columns and set the entablature up on the four jaw to machine for the cylinder spigot. Next job will be to progress  attatching the base, columns and entablature together.
Terry
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: fumopuc on December 12, 2021, 06:41:29 AM
Hi Terry,
nice set up.
I am quietly following along.
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Jo on December 12, 2021, 09:46:18 AM
Morning Terry, I've just dug out my ME that contains that article to see if the pictures are any better and they are. The article jumps around a bit  :headscratch: he starts off by describing running problems - this is actually a good sign as it tells us the engine actually runs  :ThumbsUp:  I suspect he was running it too fast these are slow running engines.

Then he describes the known problem with Clarkson castings that some were made of some real  :censored: stuff and rather hard. A bit of heat treatment on hardened castings and the use of a modern,  preferably, carbide milling cutter will sort that. Blackgates foundries are rather better than the one Clarkson used.

Not sure about the crosshead hitting the pillars - I have seen a number of these and discussed them with their builders: no one has mentioned it hitting the columns  :noidea: .

The last bit of the article he talks about making a driving pulley - clearly missed that it is an early engine and these had a square shaft that would go through a wall into the main workshop area to drive the line shafts.


We all unintentionally add our own features to our engines and find ourselves having to overcome them  ::)

Jo



Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on December 12, 2021, 12:27:31 PM
Thanks for the interest Achim & Jo :cheers:

Jo,  as yet I have had no Hard castings,  but not got to small bits yet.           Terry
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: ettingtonliam on December 12, 2021, 07:39:44 PM
Presumably the castings described in the article will have been from Clarksons. I hope the modern ones are better, but has anyone done anything to improve the patterns?
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on December 13, 2021, 09:41:28 AM
The pattern for the cross head guides is new as it had been broken. I had to wait a long time after the main castings arrived before I received these.   I can only assume mine are recent Blackgate castings but I have nothing to compare them with.  Some of the pattern "split lines" are not perfectly alligned. Overall they are adequate but not up to the quality of the Burrell ones I received from John Rex / Live Staem Models. But they were much bigger.        Terry
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on December 17, 2021, 08:42:42 PM
I know not what order of build would be followed by others, neither do I follow a planned path myself :facepalm2:   I was going ot start on the crank asembly but decided to fasten the entablature to the pillars first.  (Those of you who know the engine will wonder about the hole on the centre of the entablature...simply a cock-up.....I was on "autopilot"  Fortunately realised in time to machine a recess for the cylinder base spigot. The cylinder base is blind so it is of no consequence.)   Setting up entailed LOTS of measuring, mucking about with squares and straight edges to confirm  my marking out, etc.  Finally holes were drilled, tapped and studded. Time will tell if  the moving bits line up ok.  I also milled out the apertures for the connecting rods.       Terry

Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Jasonb on December 18, 2021, 07:07:48 AM
Good to see some more progress recently.

I think a lot of the time we can simply make whet bit we fancy or have the materials for. Though there are certain items that are best done in sequence, for example any small items that may have a reamed hole and mating turned part I always try and do the hole first and then use that to gauge the size of the mating part. Once things bet bigger I mat work the other way round eg make the crankshaft and then bore the bearings and flywheel to fit that - the flywheel being a fractionally tighter fit than the bearings as we want the shaft to rotate in the bearings and not play in the flywheel due to an oversize fit.

Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Don1966 on December 18, 2021, 06:03:02 PM
Which ever order Terry it looks good to me. Still following your progress.


Don
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on December 19, 2021, 05:52:28 PM
Cheers Jason and Don :cheers:       Terry
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Double Dutch on December 23, 2021, 02:17:16 AM
Annealed the casting in an oven at our chemical department at work.
I used 800 dgrC and let it slowly cool down over the night, so fingers crossed

After Annealing I sandblasted the castings
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on January 05, 2022, 05:22:17 PM
Fingers crossed indeed.  I look forward to watching progress. :ThumbsUp:   :popcorn:    Terry
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on January 15, 2022, 05:12:22 PM
My wife and I are just recovering from the worst "common cold" of our lives,  convinced it was covid we kept on testing but all negative.   As a result minimum shed progress.  I did make a start on fabricating the main bearings but put them down to make the crankshaft. ( it seemed an easier task for a fuzzy head)     Straightforward turning with a bit of milling at one end.  I know it's a small endmill for the job but it was all I had.
Hopefully more progress soon :)         Terry
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Jo on January 15, 2022, 05:45:41 PM
Pleased to hear you are both feeling better again Terry and you are back on your engine  :)

Jo
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on January 15, 2022, 06:44:35 PM
Cheers Jo :cheers:
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on March 27, 2022, 08:27:43 PM
It would be nice to report lots of progress, etc, but life has a habbit of getting in the way.  Busy at work..(should I still be there at 76?). We have completely rebuilt our kitchen, and also prepared our campervan for the season.  I used to be able to cope with stuff like this much more quickly :old:      However I did get to the shed today and started on the flywheel. So far no hardspots :)  I was going to bore the centre but decided on the set up pictured...turn the flywheel by manually and feed the reamer by the tailstock. It worked fine.  I shall broach the keyway as soon as the wheel is finish machined.  Hopefully progress has restarted albeit slowly.        Terry
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: crueby on March 27, 2022, 08:49:51 PM
Nice job on the flywheel.

And at 76? No - should be playing more in the shop, house, camping!
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on March 27, 2022, 09:57:20 PM
BUT.....Three short  (5hr) days per week on vintage machinery.  I could be volounteering somewhere to do the same but not get paid!
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: crueby on March 27, 2022, 10:05:45 PM
BUT.....Three short  (5hr) days per week on vintage machinery.  I could be volounteering somewhere to do the same but not get paid!
Oh, well thats not 'working'!  I was thinking (shudder) about being in an office... Ick!
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on March 28, 2022, 08:36:28 PM
I have managed to grab a little shed time and have cut the flywheel keyway.  Set up to end mill the slot in the crankshaft but ran out of time :'(
At best I may be able progress a bit more at the weekend.. :)       terry
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Craig DeShong on March 28, 2022, 11:01:14 PM
Busy at work..(should I still be there at 76?). We have completely rebuilt our kitchen    Terry

To answer your question…. NO,  you should not.  Rebuild a kitchen?  Many years ago I jacked the house up to replace some sills that had rotted out.  Today, I call a repairman when the dryer goes on the fritz.  At 75, I just don’t have the pizaz I used to have.
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Laurentic on March 29, 2022, 11:34:53 AM
Craig - couldn't agree more, happened to me too, am 76 in May, getting old is tough!  Mind is willing, body is weak and tired.

Chris
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on April 12, 2022, 09:27:12 PM
Found time to cut the keyway in the crankshaft, then made the eccentric.   I have also fitted a depth guage on the tailstock. To suppliment the graduated handle on the mill I use this for the Z axis.  Having started on the crankshaft bearings I cocked up (again) and will start again soon.
Terry
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on April 15, 2022, 08:42:29 PM
Usual routine for the crankshaft bearings,  making the split brasses first. The only material in stock was a bit too big, however I soldered two bits together and made a start.      Terry
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on April 16, 2022, 08:41:30 PM
My shed session started wll enough :)  the scrap bin yielded some bits to make the bearing "pillars".   To avoid previous mistakes I decided to position the holes using dials on the mill. I then discovered that the x dial indicator was miss-reading. I set up the independent dial to check.....0.1" on this dial compared with a reading of 0.91" on the fixed one :cussing:     A factor in my earlier cock ups.  Dial in the bin I moved on.  My next discovery was that my machine vice was allowing my part to "tip" slightly and produce a few thou taper  :cussing: :cussing: Another lesson, learned the part was clamped direct to the bed after the vice was removed. I am annoyed that this is all basic stuff that I ought to have known.  Looking forward to better progress :) I also need to upgrade my end mill stock as most of the cheapies have not survived the Burrell and Charlesworth builds.       Terry
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Admiral_dk on April 17, 2022, 12:11:55 PM
Never funny to discover that you can't trust your tools  :wallbang:
But now you know what not to trust - are any of those reasonable to cure / easy fixes ?

Per
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on April 17, 2022, 07:35:07 PM
Sorted Per,   The faulty dial has been scrapped, the original leadscrew dials have been checked against a known gauge and are ok. I can work with the vice "tip" now that I know about it.
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on April 18, 2022, 08:12:14 PM
A bit more done today,  bottom bearing pillar ready to silver solder. Top to do now.    Terry
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on May 20, 2022, 07:42:03 PM
Been playing in the shed again......  finished the crankshaft bearings,   machined the crank and cut the base plate.  Could not resist bolting together.   I then realised that having drilled, reamed and taper pinned the crank to the shaft it has to come off again to fit the eccentric and the bevel gear. :Mad:       Not many pics as my setups are very basic and there are lots of proper stuff to see elsewhere on this great forum.     Terry
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Jasonb on May 20, 2022, 08:11:25 PM
That's starting to look a bit more like an engine now :)
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Kim on May 22, 2022, 05:04:44 PM
Hey Terry,
I'm really enjoying following your build here. I've always loved the steeple engine!
Thanks for continuing to share your work!  :popcorn:

Kim
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on May 22, 2022, 07:52:21 PM
I have decided to leave the crankshaft for the time being and have started on the crosshead guides. As they need to be an exact pair a jig is essential.  They are extremely tricky to hold. The flash was removed by Dremel and angle grinder :o   Several hard spots as expected. The bases on both guides have now been machined square and to size. Using the same jig I aim to mill the vertical slot and bring it to thickness.  I already have a jig for drilling the base fixing holes.     Earlier this year I had a bout of dis-interest and stopped  :shrug: Happily now back on it and enjoying the process.    Thanks to all.        Terry
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on May 23, 2022, 08:07:30 PM
Moving swiftly on......I set up the guide in my jig, marked out and drilled two holes for the slot ends then set to with a 5mm endmill. Opened out the slot to dimension  and all worked well.
Next I needed to drill the base.  I clamped my pre-drilled hole guide to the crosshead guide and then had to improvise :headscratch: Lacking anything better, I came up with the set-up in the photos! The process was to position as close as possible and clamp tight. Gentle taps with a hide hammer knocked things to where the drill bit would just slip into the hole without any deflection ;) Repeat for the 15 other holes.
Next up was to tap the 16 holes in the "table"  10ba.   Busy with other stuff for the rest of the week , then camping at the weekend :whoohoo: :whoohoo: :whoohoo:     Hopefully more progress next week.            Terry
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Admiral_dk on May 23, 2022, 09:13:24 PM
Great to see you back on this build + that you found a renewed interest in it  :cheers:

Per
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on May 23, 2022, 09:31:41 PM
Cheers Per :cheers:
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Kim on May 23, 2022, 10:00:52 PM
Wow, quite a setup you used there in pics 5 & 6 to get at the ends of those castings!  Looks like it would be a challenge to line up the spot for the hole!

Kim
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on May 24, 2022, 09:42:55 PM
Yes it was a bit Kim!   but gentle taps with the hide hammer brought the non-running drillbit so that it could be lowered into the jig hole concentrically. at that point start the machine and drill the hole....   with a 1.4mm drill you can see and feel it when it is not lined up.
I am sure that when Jo does her's she will have proper  tooling for the job and we will see how it should be done.        Terry
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Jo on May 24, 2022, 09:53:16 PM

I am sure that when Jo does her's she will have proper  tooling for the job and we will see how it should be done.        Terry

I will be digging out my old shaper box table  ;)

Jo
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on May 31, 2022, 07:59:14 PM
I decided to machine the big end rod next. Having been warned about it's crosshead hitting the table I thought it best to check. I don't "do" CAD so just used a pair of calipers. On my castings there would be interference if made to drawing.  The solution would seem to be to mill a tad off the inside of the webs that form the underside of the table to enable the crosshead from the bigend rod to fit inside them. I will measure properly in case the rod needs to be shorter.  Progress will be even slower soon as I have aquired two motorbikes to restore.       Terry
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on June 03, 2022, 09:02:44 PM
Today I made a start on the big end crosshead.  Several methods, I settled for cutting from solid bar rather than fabrication.  A bit of milling
and some filing.....mostly by eye as I do not like filing buttons.  The two webs on the table were relieved and leaves enough clearance.  Another measure tells me that bigend con rod is too long as drawn so will be made to suit.   Terry
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Kim on June 03, 2022, 10:41:43 PM
The part looks fantastic, Terry!   :popcorn:

But what causes your dislike of filing buttons?  Just curious.  I find that my eye isn't very round.  I have much better luck using filing buttons myself. Must be my astigmatism!  :Lol:

Kim
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on June 04, 2022, 09:52:13 AM
Hi Kim,     Thanks for your interest.    Soft buttons are not a lot of use and hardened ones ruin files which are costly to replace.  I take the easy way out and do it by eye ::).  Parts end up adequate for my use as they not intended to appear at shows, etc.       Regards    Terry
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Kim on June 04, 2022, 03:10:01 PM
Soft buttons are not a lot of use and hardened ones ruin files which are costly to replace.

Interesting... I never thought about that before!
Thanks for taking the time to explain it to me :)

Kim
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Jo on June 04, 2022, 03:48:09 PM
It takes a good eye to hand file curves. Well done Terry  :wine1:

For those who can't  Soft and hard buttons....

I use soft buttons and I screw them tight against the item. Often I will use marker pen on the buttons and when filing try not to catch the buttons but use them as an indication that that bit doesn't need any more filing. Also as the additional width of the buttons means it supports the file and keeps the edge of the item square. Soft buttons can be used when you draw file across the item as well as following the curve  :)

Hard buttons are used loose  on an arbour: Because they are hard they must rotate away from the file when it tries to rub against it. What Ray has said about hard buttons wearing the files occurs if the buttons do not freely rotate and you cannot draw file the other way without risking damage  :hellno:.

You an also use freely rotating soft buttons  :)

I am sure Jason will be along in a mo to tell us all about using rotary tables  ::)

Jo
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Jasonb on June 04, 2022, 03:56:43 PM
Rotary tables are so last century have you not heard of the new fangled CNC :Jester:

Must admit now that I also have the SX2.7 sitting in the workshop one of the rotary tables seems to live on that so it is quick and easy to use that for rounding over. And a carbide milling cutter will round off hard iron which would otherwise round over your file's teeth. The mechanical methods do also have the advantage of being able to round over solid items so you don't need a hole for a pin like you do with buttons

The one problem with buttons is that you can only roll the file on them for 180deg, a part like Terry shows has a longer arc which is not an issue when milling but means you start having to file across the buttons which will either wear if soft or muck up your files as he says.

I do still make use of buttons, I've never hardened them (also use loose)and they generally last for more than the job they were made for so can be kept in a box for future use and easy enough to knock up a pair of new ones from mild steel. Buttons also work well with a linisher but make sure you have them secure as they do spin up to quite a speed.
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: crueby on June 04, 2022, 04:05:10 PM
Rotary tables are so last century have you not heard of the new fangled CNC :Jester:

...
I use CNC on my rotary table...  Count Number Cranks, right?!   :Jester:



Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on June 05, 2022, 12:52:52 PM
Last century maybe but that's when I did my engine fitter appreticeship. :old:  Two years of filing / benchwork,etc.,  then shapers, vertical and horizontal boring machines and a huge variety of lathes.
There must have been milling machines but I don't recall seeing any and had no experience of them until aquiring my little Raglan.  Hence my reluctance to do this little parts on the mill and stick to filing.
Thanks for the compliment Jo,  but a hand finished part rarely compares well with a nicely machined one.  I continue to delight in the craftsmanship that you all display. :Love: :popcorn:         Terry
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on June 06, 2022, 09:21:23 PM
I mentioned earlier that the big-end con rod was too long as drawn. I was wrong as the underside of the crosshead needs to clear the crank at bottom dead centre.   I have noticed some errors on my build probably due to poor measuring >:(  The engine has been dismantled, boxed and put away for a while as I continue camping and sort out my two mortobike rebuilds.  As a result this thread is "on hold" for a while but will hopefully continue with renewed enthusiasm in the autumn.    Cheers for now    Terry
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Jo on June 07, 2022, 07:24:17 AM
Sorry to hear that Terry  :( I hope you wrote down your findings so that you don't have to re-find them when you pick it up again.

You have not told us anything about your new bikes, it would be nice to find out a bit more about them  :). In my younger days  :old: I restored a few motorcycles of my own before someone (MEM member Old Bill) introduced me to model engineering  :embarassed:.

Jo
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on June 08, 2022, 09:38:39 PM
Cheers Jo,     Nothing exotic I'm afraid,  just a couple of 1963 Royal Enfield 250cc. Dismantled by their owner 45 yrs ago and dry strored ever since. A last (failed) attempt by Britain to fend off the imports.
I have owned nearly 30 bikes in my time but never an Enfield so will be a change.            Terry
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: Admiral_dk on June 08, 2022, 10:20:37 PM
As a Biker for Life (and never owned a car), I'm curious too - any pictures ?

45 years in dry storage æh - that is a long time, so even better if they are oiled (so to speak)  ;)

Enjoy the time with this project too  :cheers:

Per
Title: Re: Murdoch-Aitken "Steeple" engine
Post by: scc on June 09, 2022, 03:29:55 PM
No pictures as yet Per.   No, the bits have not been oiled :( so a bit of work ahead.      Thanks for your interest.          Terry