Model Engine Maker

Engines => From Kits/Castings => Topic started by: Twizseven on January 06, 2020, 09:32:49 PM

Title: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on January 06, 2020, 09:32:49 PM
Finally bit the bullet and decided I'd better try and do something with one of my casting sets.

I recently visited Graham Corry and had a set of the CHUK Flame Licker/Gulper castings off him.  Several members of this forum have built this engine over the last couple of years, including very recently Jo and also Graham himself.

I'm sure my build will be a demonstration of how not to do it.  I decided to start with this engine as the castings are of a reasonable size unlike some of the other sets I have squirrelled away.

This will not be a quick build and I'm sure there will be the odd swearword as I progress, or don't. as the case maybe.

I started with the base casting and due to its relative size decided to use the Colchester Student and its large 4 Jaw chuck.

This is quite an awkward casting to hold and i eventually managed to get it centred and held against the chuck jaws by means of large revolving centre in the tailstock pushed hard up against it.

I wear glasses but decided to play ultra safe and wore a full face visor whilst cleaning of the diameter and base and the inside bore.  The thought of it flying out of the chuck did not appeal.  Used tipped tool and ran at a nice slow 54rpm.

The centre of the underside will have to be cleaned up at a later point in time as I had nothing I could use to get between the revolving centre and the casing.

Please feel free to point out any stupid practices or to provide helpful suggestions.

First photo shows the set of castings.  In Picture 3 you can see part of the casting where the mould had a little issue.  I had to be very careful when cleaning this area up.

Colin

Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Jo on January 06, 2020, 10:29:58 PM
 :) Nice to see some progress on your Chuk Colin.

I don't think I bothered with turning the outside/bottom of my base as it decided it was flat enough and it was supposed to be a casting  ;)

Jo
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Alyn Foundry on January 07, 2020, 11:44:39 AM
Happy New year Colin.

Mirroring Jo's comment, likewise.   :)

I've mentioned many times that I spent hours at the premises of AWR engineering, learning or trying to learn the " craft " of  machining. Many of Alex's jobs were small batch repetition. His philosophy was that you only changed lathe chucks when " absolutely " necessary. It's not only time consuming but heavy work if you're running a large lathe.

I designed the pad for the cylinder mount to be compatible with my 8" monoblock 3 jaw chuck, the square bit would " just " fit between two jaws. Once running fairly true you can centre spot and bring in the tailsock rotating centre for added security.

The use of the four jaw chuck obviously improves the grip immensly and in the Model engineering workshop time is spent pleasurably, I hope? 

I'm very pleased to see that you didn't encounter the same problem as I did with my base.

Please don't hesitate to ask questions Colin, and don't forget to post with the FB group.   ;)

Cheers Graham.
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on January 07, 2020, 10:35:59 PM
Hi Graham, Happy New Year to you.

When I came to look at the base in daylight to mark the center for the exhaust port I realised that although the casting was centred nicely in the chuck when I machined it when looking at the top face the the boss was around 5mm off centre. :ThumbsDown:  This would have irritated me for ever.

I lightly cleaned up the face of the boss on the linisher and then put a coat of marking out blue on it.  As the main diameter of the boss appeared to be 60mm I cut a paper circle out to this size and placed it over the marking out blue.  Then able to put a nice centre pop in the middle.

I used this centre pop to centralise the base in the 4 jaw chuck, the faced it off, drilled and bored the 20.5mm hole for the exhaust  exhaust port and recessed the face for the exhaust valve and very slightly for the base of the cylinder.

Then turned a 20.5mm mandrel clamped the base to it and refaced the outer and inner faces of the base.  Much happier with the result now.

Then decided to have a go at the flywheel.  Mounted in in the 3 jaw chuck with the jaws opening outwards to hold the flywheel to the chuck.  I had to pack one jaw with a double thickness of cardboard to get it to run true but I only had a 5mm register to grip the flywheel.  I centred the boss and used the revolving centre for additional support.  I was able to face the periphery of the flywheel and the front face but due to jaw location could not do rear face.  I wanted to clean up the centre boss whilst it was supported by the centre.  I needed a long narrow right hand tool which unfortunately I do not have.  Tried many options and suddenly had a light bulb moment.  I could turn my left hand tool upside down and run the lathe in reverse.  Amazingly it worked,  The finish was not prefect but at least I had removed the outer hard skin of the casting.

I removed the revolving centre, drilled 6mm, 8mm, 9.8mm through the boss and then machine reamed it to 10mm.  This all went ok so turned flywheel around and cleaned up remaining faces and the other boss.

Will attack the cylinder next.

Seems to have taken me a long time today.

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on January 07, 2020, 10:36:58 PM
Current state as end of day
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on January 08, 2020, 11:02:10 PM
Decided to start with the piston and get it down to largest size possible.  It cleaned up at 40.34mm diameter.  This gave me something to aim for whilst boring the cylinder.

The piston has quite a casting draft and it needed a good push with the tailstock onto the chuck.  Was not happy holding it on external surface but held it internally on the small 3 jaw chuck on the Myford 7.  I also cleaned up the inside.  Started with boring tool then cleared the bottom of the casting with a 10mm carbide slot mill held in the drill chuck in the tailstock.  This was an interesting exercise, the drill chuck in the MT2 tailstock kept kicking up.  This finally stopped once the bore had started and it could guide the cutter.  I finished with a 5.5mm piston crown and wall thickness around 3.5mm.  These will both be thinned down once piston sized to bore.

Then moved onto cylinder. Unfortunately the jaws on my 3 jaw chuck were not deep enough to hold onto more than one cylinder fin.  I had in all centered and started to  gently machine the end face.  This finished with a very slowly occurring disaster.  The cylinder decided to remove itself from the chuck. :facepalm:  Luckily no damage was done. :) I found some of the brown stuff I had just removed from my fathers workshop which was almost the right size for the bore.  Quickly turned it down and made a short plug to put in the end of cylinder.  Now able to hold the cylinder on the first section of the cylinder before the start of the fins.  This worked great and soon had the face nice and flat.

Fitted the big 4 jaw chuck to the lathe and put the newly faced side against the chuck, bit of cardboard between the casting and the chuck jaws and centered it all up.  I just used a rough block of wood between the casting and the tailstock centre to hold the casting flat against the chuck.  Centered the casting using a combination of the fins, bore and outer end of the cylinder.  I left the block in place whilst turning down the end of the cylinder to provide a suitable surface for the fixed steady.  I have never used the steady before.

Fitted the biggest/longest boring tool I have got, 7/8" square Sandvik Coromat.  The first few passes i did by hand but then used power feed to take out 1mm at a time. I had decided I could go as close to 40mm bore diameter as possible.  At 39.970mm I then ran the tool back and forwards under power for three full passes.  This took around 1hr.  Final dimension would appear to be 40.15mm.  I have measured this using spring calipers telescopic gauges and then reading them with micrometer.  They both concur and not only that the bore appears to be parallel. :cartwheel:

Tomorrows task is to find a honing tool.  I used to have one of the spring cylinder hones but last used it 30 odd years ago.  It appears to have vanished.  Once I have honed the bore I will get the piston down to final size.

Colin

.
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Jo on January 09, 2020, 08:49:12 AM
Doing well Colin  :)

Those brake honing tools are very cheap on Flea bay. For the outside of the piston: you don't have much to come off I find holding a stone against the outside is a good way of honing it to take off that last fraction for the fit.

Jo
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on January 09, 2020, 11:40:11 AM
Jo,
Iím please with how itís going so far.  Should have a brake cylinder hone by 5 this afternoon.  Planning on leaving cylinder in chuck and putting hone in tailstock.  Run at slowest 54rpm with some paraffin and see what transpires.
I think The piston will need a quick skim first before stoning.  I was thinking of using 1200 grade wet and dry again with paraffin or possible oil.

I am hoping to leave the cylinder in the Colchester and machine the bearing standard on the Myford.  I am hoping to be able to make the stand an interference fit (or loctite if I get dimensions wrong).  The plan is to bore out the outer portion of the stand whilst it is held on long mandrel ( simlilar to the way you held yours).  I can then machine appropriate dimensions on the cylinder on the Colchester.

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Jasonb on January 09, 2020, 12:08:22 PM
Looking good

You may want to up the speed with the hone to avoid stalling your so far rapid progress, I then to run then 500-740rpm. I tend to use the drill press as you can work the hone in and out faster with the quill to get a cross hatch or better still a sit's not that big a bore just hold in your hand and work up and down. Doing it with the tailstoke will give more of a circular hone, also run the stones just beyond the end of the bore, hopefully you have a big enough hole in the chuck to do that if sticking with the lathe.

Back any abrasive sheet with a bit of flat bar, MDF or steel rule.
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on January 09, 2020, 01:00:43 PM
Jason,
Thanks for that tip.  Many years ago I had to hone the bores on a 803cc Standard  8 engine.  I used one of the larger 3 stone spring loaded hones and my fathers antique Wolf Power drill.  This was a big drill with IIRC a 300rpm top speed  I used this and kept raising and lowering it in the bore till I was happy with the result.  Knees and back were b......d by the time I had finished.

Will back the 1200 wet and dry with  piece of steel rule.

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Alyn Foundry on January 09, 2020, 02:30:51 PM
Your progress is rapid Colin, well done.

Ah, Wolf power tools, well built and unstoppable!!

Whilst still an apprentice at the Water company I remember two of the garage staff drilling a large hole with a two man Wolf drill.  Next thing, it bit in hard and the two guys ended up running around the work until the power cable pulled out of the socket. 'Twas scary at the time but everyone laughed about it later.

I too have one of those drills you used Colin, with the older, better drill bits of the past they could easily become a wrist breaker, you had to be on your toes!

Cheers Graham.
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on January 09, 2020, 05:16:50 PM
Graham,

I still have the drill.  It has a lot of torque.  As well as handle with trigger it has a chest brace and a 1" dia steel tube on opposite side to handle.  It has swung me round many years ago in the dim and distant past.

Just picked up brake cylinder hone.  So tonights job is...............................boring.....sorree honing

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on January 11, 2020, 04:06:39 PM
As I said in last post, a boring evening.  I started of leaving the cylinder in the lathe chuck and used electric drill with the cylinder hone attached.  This was not very comfortable so put cylinder in vice and found this a lot easier. Once I was in position that the head of the piston would enter the cylinder about 5mm I reversed it and tried the open end, If did not fit then polished the piston up concentrating on end that did not fit.  Kept alternanting between running the hone down the bore and polishing piston as required.  Was 90% of way there when wife who had gone to bed rang me to say I was making too much noise (tapping piston out of bore with broom handle) as it was 11:30pm. :hammerbash: Oh Dear  What a shame. Gave up for the night.

Next morning carried on for around 1hr till piston slid nicely from one end to the other.  Just had to part it off from the fixing stub.  Before removing this stub I drilled 4mm for a 2BA tap for fixing gudgeon pin fork.  I put it in 3 jaw chuck on Myford  with cardboard round to prevent damage but did not want to tighten it too much as piston walls are just under 1.5mm.  As soon as parting tool touched it started to move, stopped quickly and decided that careful use of hacksaw was required.  Once sawn off I was able to reduce top of piston  by 1.5 mm to 3.5mm.

In order to finish machining the cylinder I needed a solid mandrel on which to mount it.  Found a suitable length of (dubious) steel and turned it down from 25.6mm o just over 22 mm for most of its length.  This left a shoulderat the end nearest the chuck.  Turned the other end down ready to run a M16x2 die over it for a fixing nut.  Could not work out whether it was the steel or the die that was absolute rubbish.  In the end I had to turn the end down well below 16mm dia and was left with threads minus their crown.  The nut still holds. :ThumbsUp:  Next need a pair of washers with 22mm bore and spigot 40.3mm for a good fit in piston bore.  Found big chuck of steel, Chucked it up and put centre in end then turned it down to 46mm.  Removed centre and fitted fixed steady then drilled out at 3/4" and started to bore for 22mm.  By now it was 21:30p.pm and time to go to pub for a pint. :cheers:

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Alyn Foundry on January 11, 2020, 06:10:52 PM
Hi Colin.

I've just noticed that you haven't got the " lip " at the top of the cylinder  for the exhaust disc, is this the next operation ?

Cheers Graham.
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on January 11, 2020, 06:54:47 PM
Graham,

Yes that is next operation once I have made the sized washers to hold the cylinder central on the mandrel.  At moment staring at a piece of 1/2" brass deciding whether to machine it down ti make the gudgeon pin boss.

Also just ordered some 1000 grit silicon carbide for giving the piston/cylinder a quick lap.

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on January 12, 2020, 07:56:02 PM
Last night decided to cut piece of 1/2" sq. brass down to make the gudgeon pin mount.  Decided to do this on the Cowells mill in the warm in the office.  Machined to size then found long 4mm end mill and and machined slot for the little end to fit into.
Left this to continue another evening.

Continued making mandrel.  The chunk of steel for the washers was finished bored to 22.6mm and then turned down spigot to fit in cylinder. and the correct dimension to clear the boss's to be machined into base of cylinder.  This all went okay.  Then disaster struck.  I was using a very nice 4mm wide ISCAR tipped parting tool which has worked beautifully in the past and with power crossfeed.  Started to cut and then engaged crossfeed (set to slowest possible).  It started okay started to grumble and before I could cut the power it threw the piece out of the fixed steady and the 3 jaw.  :censored: The fixed steady had its top leg pushed upwards and it pushed it past the screw which does its infeed.  >:( I think the fact that it went this way saved any proper damage other than the slight bend in the screw for the top leg.  Decided power parting with this piece of steel was a big NO NO.  Threw it in the 4 1/2" bandsaw then faced it off.  Reset chunk of steel in 3 jaw, trurned washer to size and bandsawed it off and then faced it.  Finally had a mandrel and fixing washers and was able to mount cylinder on mandrel and tidied up the fins and grooves.

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Alyn Foundry on January 13, 2020, 03:41:49 PM
Progressing nicely Colin.

I hadn't realised that a volunteer from the Anson engine museum had captured this on video.

The ONLY CHUK 3 !!

QHO5y9bMegw
Cheers Graham.
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on January 13, 2020, 08:43:11 PM
Thank you Graham.

How much cleaning up would you normally do around the fins and grooves in the cylinder.  I have gone in with a narrow round tipped tool and taken all the casting flash of from the sides of fins and bottom of the groove.  I have tried not to removed very much of the sand cast effect.  Would you normally leave it like that or completely clean out and completely smooth the surfaces.  All the fins are now cleaned up to the same diameter.

So how many of each variant CHUK1, CHUK2 and CHUK3 are there out in the wild.

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Alyn Foundry on January 14, 2020, 11:44:29 AM
Good morning Colin.

To be honest it's down to personal choice with regards to the cylinder finning.

They did such a good job of the castings at Rhuddlan that only minor fettling was needed to make the cylinders presentable.

As to numbers, I didn't keep a written record. I was getting the design ready for Chester UK to start offering kits when the announcement of Rhuddlan's closure was made.

There are just two of CHUK 1 MK 1 and a couple more of the MK 2's. CHUK 2 see's the most, at less than 10 with CHUK 3, seen above being the " lonely " one.

Cheers Graham.
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on January 20, 2020, 05:50:42 PM
Finished off the cylinder bottom by turning the boss for the exhaust valve and the locating boss to fit it in the base.

Earlier in week I had machined the a small piece of brass to make the gudgeon pin mount.  I was going to do the next step on the Cowells Mill, but decided to revert to the PBM-2000.  I had just swapped a spare R8 Clarkson mdeium collet chuck for a small Hauser plain shank boring head which has come with a very small boring tool already mounted in it.  I Needed an 8mm dia hole through the piece and decided to start at 6mm dia so shoved a 6mm slot mill in ER32 collet chuck and put initial hole in.

Swapped to boring head and slowly (very slowly) worked my way up to 8mm.  This took me about one and half hours.  Part of the issue was getting use to the boring head and tool flex in the small dia tool, the second problem was sizing the hole.  The only tool I had to fit the bore was a Telescopic bore gauge but this needed a 7.5mm hole before it would fit in.  To be able to get clearance below the cutter I was having to drop the knee a fair amount (50 turns of handle), take measurement and then wind back up another 50 turns.  This was a bit wearing.  I need to fit the Z Axis power feed which is sitting in box next to the machine.  Eventually got here and the bearing fitted. :cartwheel:  Wanted to radius the ends so moved to the BCA jig borer after having made a small locating stud to fit in the rotary table and the bearing hole.  Using 1/4" end mill I first did upper radius and then the lower one.  Cleaned up sharp edges, fitted bearing, happy with how it turned out.

Next part was the bearing upstand..  The cylinder was still set up on mandrel in the Colchester so I decided to use the Myford.  Needed a mandrel making to support the upstand, so found a piece of 3/4" bar put it in ER32 collet chuck, put centre in the end, then turned down to 1/2" dia. and put a 3/8" UNF thread on end.  With this made Fitted three jaw chuck and centralised the casting.  I needed a spotfaced hole in the centre and put long 1/2" slot mill in Jacobs chuck.  When spotfaced put 15/32" drill through the casting.  Changed to boring bar and took hole out to just under 1/2" dia, opend the spotfaced area to 7/8" dia then put 1/2" reamer through  the hole.

Bolted casting to the mandrel and put into ER32 chuck.  Due to the weight distribution it was a bit unbalanced to ran quite slowly and turned the periphery up to match diameter of the fins on the cylinder, then faced the bottom.  As I intended to try for a close fit with the top of the cylinder (ha ha) I now needed a hole 46mm dia by 6mm deep in the bottom of the casting.  I had turned the top of the cylinder to 46mm whilst it was still in the Colchester. This took some time, in fact it took lots and lots of time. :ThumbsDown:  I started off by scooping (very technical term) bits out with a round nosed tool, but obviously could not get near the edge.  Then used a profiling tool to remove some more.  Gradually swapping tools about I headed down to 6mm.  I wanted to get a boring bar in, buteven using the smallest one I had It kept fouling on the boss that was slowly emerging around the mandrel.  Kept making the mandrel smaller till I could get the boring bar in and complete the hole to size.  This also was a bit of an exercise.  I was having to use internal spring calipers and external micrometer to get to size.

Eventually go to size and had to bite the bullet and take the cylinder of the mandrel on the Colchester.  Tried it cylinder in bore and it fitted. :cartwheel:  BUT would not go fully in.  I used engineers blue to check when  I had a mating surface.  After a while i twigged that the internal corner in the base had not cleaned up. I found a old tool my father had made 30 odd years ago which cleaned right into the corner.  Once this done I had blue on both surfaces.  :whoohoo:

The three main castings now fit together.  More work still do do on the upstand.

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on January 20, 2020, 05:53:10 PM
Few more pics.
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: mnay on January 20, 2020, 07:45:33 PM
Great looking flame gulpers.   Are the plans still available for sale?

The castings are beautiful, but I gather from reading the build notes that they are no longer available.

Thanks, Mike

I will continue to follow along.
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on January 20, 2020, 09:28:49 PM
Question to Jo or Graham

Is there a centre to centre distance for the crankweb for the crankshaft and the big end. :headscratch:

Or is it whatever can be squeezed out of the casting.

Colin

PS Silly question, just re read page one and noted the Stroke is 2", so obviously center to centre is 1".   :facepalm:
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Jo on January 20, 2020, 09:38:33 PM
I would check your casting I seem to recall something about the pin may be a little close to the edge  :noidea:

I cut my one out of a bit of steel rather than using the castings as the one I had was a little chilled (hard as glass) and I could increase the counter balance size  :)

Jo
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on January 20, 2020, 10:09:19 PM
Jo,

Many Thanks, I'll check that.

You have Surus helping.

My helper is a little more active. :ROFL:

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Alyn Foundry on January 21, 2020, 11:25:57 AM
Good morning.

Love the Ginger moggy Colin, what's it called?

Regarding the stroke, if you can squeeze a little more from the engine, the better!! But otherwise it's 50mm or 2" ....

I can see some extra sketches, from Jo per chance?

Your overall progress and attention is looking great Colin, won't be long now.

Cheers Graham.
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Alyn Foundry on January 21, 2020, 11:35:01 AM
Great looking flame gulpers.   Are the plans still available for sale?

The castings are beautiful, but I gather from reading the build notes that they are no longer available.

Thanks, Mike

I will continue to follow along.

Hi Mike.

Please check your inbox... ;)

Cheers Graham.
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Jasonb on January 21, 2020, 01:13:14 PM
Mike if Graham's PM does not contain the info that I think it does there are links to drawings on this site for a smaller version that does not need the castings that could easily be scaled up if desired.
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on January 21, 2020, 03:09:02 PM
Graham. The cat is called Tigger. He loves being with me. Trouble is swarf and cats paws do not go together so have to vacuum the floor as often as I can.   The drawings were some of my sketches. Trying to keep a log of the build and all issues/problems I have experienced.  Most of them due to my lack of thought of Incorrect setup or lack of required tool.   Depending on whether or not it works at the end of day I might do an article for MEW. (If they want it/deem it suitable)

Just bored 40.3 hole in bearing yoke and when fitted on cylinder can pass the piston through the two of them. Cleaned the pedestal up 1/2mm or so wider so once painted can still insert piston from the top.  Need to do a bit of fettling with file/die grinder to clean up transition from machined edge to casting.
Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Alyn Foundry on January 21, 2020, 04:28:41 PM
Hi Colin..

MEW ?

A site specifically designed for cats ??

 :lolb:
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on January 21, 2020, 06:57:37 PM
 :lolb: :lolb: :lolb: :lolb: :lolb:
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on January 21, 2020, 10:07:41 PM
Continued with the bearing yoke.  While it is still on the mandrel I turned down the lower edge of the rim using a profiling button tool.  I wanted the top of  the cylinder to look like a seventh fin.  I removed enough material so that when placed on top of the cylinder the two diameters were the same.  No photograph of this.  Once happy with this I removed it from the mandrel, turned it round and put in 3 jaw chuck with some thick cardboard to protect the outer rim.  Because it is only held for about 5mm depth, in order to ensure this stays in the chuck I turned a 1/2" spigot on other end of the mandrel and used this to press against the casting using a revolving centre in the tailstock.  I could now machine the top face of the bearing yoke on which the bearing block is mounted.  Without the pressure form the tailstock there is a very good chance it will fly out of the chuck.

Next step was to remove the mandrel and then bore out the centre to 40.3mm to match the cylinder bore.  This was taken very steady due to reduced hold of yoke in the chuck.  As the hole became larger it was necessary to angle the boring bar to clear the bearing block.  Whilst winding the carriage back to as to be able to measure the bore I forgot to rotate the chuck to move the bearing mount out of way and dragged the whole thing out of the chuck. :facepalm:  Reset it back in chuck and continued to bore was 40.3mm.  I needed to clean up enough of the inner edge of the bearing yoke to be able to fit the piston from this end of the cylinder (including when painted).  This meant cleaning up the inside of the bearing yoke casting for at least 33mm (just over the length of the piston).  This meant several angle changes of the boring bar to keep clearance of the casting whilst boring.  When this was done tried the yoke on the cylinder and checked the piston would pass through. It did.  :cartwheel:

Now moved back to the mill to machine the inlet valve face on the cylinder and also the inlet port.  My mounting of the cylinder was a bit Heath Robinson.  Mounted the Dividing head on the table, aligned with X axis and fitted Myford 3 jaw chuck fitted with internal jaws.  Held the cylinder by the inside top of the bore.  Had intended to use  Centering Gauge to find center of cylinder but even on Bridgeport sized machine there was not enough headroom.  Next thought, rotate dividing head till horizontal, thick end of the casting over the vice, put packing under end and at sides so could be clamped in vice and then fitted the piston.  The used laser centre finder to pick up each side of the piston in turn and then halved reading to get center.  Zeroised X-axis on DRO and then picked up base of cylinder and zeroised Y-axis.  Then faced of the port and took it down to the requisite 14.5mm from the bore.  The inlet port has to be max 40.5mm wide and 6.36mm deep and pass right through across its full width to the bore.  Used a stub drill to mark at 16.82  mm each side of x-axis center line, then drilled 6mm through to the bore.  Swapped to Clarkson chuck and fitted 1/4" slotmill.  Took this straight down through the casting in both drilled locations, then removed the area between the holes taking 1.5mm with each pass.  Amazed no breakages, and a clean hole.  :whoohoo:

Remove from mill put hone through bore quickly to clean up and then tried piston.  All okay.

Loosely assembled all bits and it now looks as though I am making progress on something for the first time in years.

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on January 21, 2020, 10:11:33 PM
And last couple of pics.

I picture 56 the piston can just be seen through the inlet port.  It can also be seen in pic 57 in top of the bore.

Pic 58 shows how the section of casting at the top of the cylinder has now become fin number 7.

Colin.
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on January 23, 2020, 09:32:37 PM
And a little bit further.

Blued up the top of the bearing yoke found center lines, drilled, tapped 2BA and then ran milling cutter round all four sides. The two back corners were hard as glass and the cutter really struggled, ended up filing them square. :(

Tidied up the front of the base below the inlet port with bullnose cutter.

Found piece of 1 1/4" square brass and decided to use this for the bearing housing. Squared up the base and top and found centres, drilled it out to 16mm, and then bored up to 25.98mm for the bearings. Checked bearing fit, slightly looser than I wanted, but at last its round and square.

Turned it the right way up and then drilled all the way through for the fixing studs,  Decided to run a 1/4" radius cutter down the two edges, then counterbored for the nuts.  Then tapped the center 5/16 x 40 ME to put in a small oiler cup.

Moved onto crankweb, linished the back and then centered in 4 jaw chuck on Myford so I could drill and bore the boss to just under 10mm diam. ready to ream it.  Once reamed I could fit it on to a expanding mandrel to turn the diameter and then face front and back.  Move back to mill and set it parallel in vice with the side with slightly less to remove uppermost.  Milled flat then turned over and repeated.

Cut a short stub of 10mm silver steel and then was able to assemble flywheel crankshaft, bearing mount and crank web.  Quite pleased with how it looks.  Fiund small piece of brass hex and turned up an oiler cup on the Cowells lathe.

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on January 23, 2020, 09:33:53 PM
And the next few.

Quick question for Jo. What size bearings did you use for big end and for the cam follower.

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Jo on January 24, 2020, 08:01:10 AM
Getting on nicely  :)

Quick question for Jo. What size bearings did you use for big end and for the cam follower.

The Big end bearing is a standard common size bearing for disc drives, with 8mm OD/3mm ID bearings on the little end and on the CAM follower.

Jo
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on January 25, 2020, 01:26:09 PM
Thank you Jo.

A little bit further.  Measured the offset between the center line of the cylinder and the inside edge of the crank bearing (in its housing).  I need the crank web to be total of 9.75mm to put conrod in correct position.  Needed to remove almost 8mm.   This would leave me a small boss of around 5mm for grub screw to fix web to crankshaft.

Work out that I could get a 2BA thread hole 4mm in from end of crankweb for the big end fixing.  This gives me a crank throw of 27mm and the conrod can be 120mm long center to centre.

Ordered various bits of brass material for amongst other things the cam roller bearing mount.

This morning turned down some 5mm rod to make a pair of 2BA studs.  Thought I would do this on the Cowells lathe.  Only got so far as I could not hold the turned down bar well enough in the collet chuck (Cowells early version) to cut the thread :censored:, even with the die set quite loose.  Reverted to the Myford to do this.  With studs fitted I could then fit (Loctite 638) the bearoings in the housing.  The studs act as an internal spacer for the bearings to be pressed up against, and more by luck than judgement they are flush with the outside faces.  :D

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on January 26, 2020, 11:01:58 AM
Jo,
When you built your engine you machined the cam initially on the lathe to give the 62mm diameter  and then transferred to the mill to get the required profile by offsetting the cam and using  boring/facing head set to give 65mm diameter cut.  What I do not understand is why you had to run the mill backwards and machine in an anticlockwise direction :headscratch:.  Could you (or anyone else who understands) please explain the reason why.  I guess there is some logical reason.

Many Thanks,
Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Jo on January 26, 2020, 11:09:37 AM
Because of the direction of the teeth on the milling cutter being used in the boring head.

Jo
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Chipmaster on January 26, 2020, 11:34:08 AM
Hello Colin,
You don't need a milling machine to profile the cam, simply offset it in a four jaw chuck see post 9 in my build log from 2015. I think 1/4" offset was required. The piece of paper was cut out of the plans which included an A4 page of cam profiles.

http://www.modelenginemaker.com/index.php/topic,5124.0/all.html

(https://live.staticflickr.com/358/18921512459_78458cf6ba.jpg) (https://flic.kr/p/uQ2Grr)

Andy

 (https://flic.kr/p/uQ2Grr)
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Alyn Foundry on January 26, 2020, 11:42:23 AM
Good morning Colin.

You have made some rapid progress over the last few days, well done.

I've been busy with some pattern refurbishment as another run to the foundry is imminent.  :)   We're hoping to have a " NEW " engine for the upcoming event in June.

All the cams on my engines have been " hand " formed, scribed and then cut with a hacksaw. The rough face then " draw filed " down to the line. A lick on the polishing mop finishing the operation. I suppose this goes back to the days when I was building engines without having a milling machine!

Your CHUK is now reaching the " fiddlely bits " stage, looking forward to seeing how you get on.

Cheers Graham.
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on January 26, 2020, 11:53:33 AM
Jo, Andy,

Thanks for quick responses.  Interesting that Jo's offset was 9.5mm and Andy's offset is near enough to 6.5mm.  How is the difference in offset going to affect the running of the engine?

Graham,
Yes the fiddly bits.  am waiting for some material to arrive but don't think this will be till wednesday.

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Chipmaster on January 26, 2020, 01:12:56 PM
Colin, I guessed the offset or lift was 1/4Ē, on reflection it was probably 3/8Ē to ensure the valve seals the cylinder port on the power stroke but opens enough to draw in the flame.

I set the timing for slow running on my engine

OvVYFZbRB-c
Andy
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Jasonb on January 26, 2020, 01:43:00 PM
Colin, if you do decide to run your boring head backwards make sure it is not one that can screw off the arbor. I have a couple of bars ground for external cutting so use them and run in the normal direction, would have thought those with fancy tool and cutter grinders may have actually used them :LittleDevil:
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Alyn Foundry on January 26, 2020, 01:52:13 PM
The adage....

" many ways to skin a cat " comes to mind, particularly in engineering.

However, I do like Andy's solution.... Hmmm, surprised I hadn't thought of that one myself lol....

Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Chipmaster on January 26, 2020, 02:14:20 PM
Hi Graham, yes I attached the paper pattern to check that I would be machining the authentic cam shape as indeed it did without any further work on the cam face.
Andy
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on January 26, 2020, 04:16:30 PM
Just checked my Lenz boring/facing head and do have suitable tooling to run in normal direction. This will be another Ďfirstí as I have never used it before.
Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on January 26, 2020, 04:18:59 PM
Jason, 
My other boring head would certainly unscrew if I used that backwards.
Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Alyn Foundry on January 27, 2020, 12:05:09 PM


Graham,
Yes the fiddly bits.  am waiting for some material to arrive but don't think this will be till wednesday.

Colin

I too have some bits ordered Colin, also expected this Wednesday....   ;)
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on January 27, 2020, 02:47:13 PM
Graham,  Just turned camshaft casting to it diameter. Bl...y H..l itís hard. Well chilled on 50% of perimeter. Most tools just slide off it. Could not touch it on the Myford. Put it in Colchester with big tipped cutter and took lot of it off. About to attempt milling the profile.
Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Alyn Foundry on January 27, 2020, 03:07:45 PM
Hi Colin.

The only consolation is that we won't be using their services again....

Try annealing the casting before the next operation, heat up towards bright Orange then immediately bury it in dry sand. Hopefully you'll have a softer Iron to work with.

Cheers Graham.
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Jo on January 27, 2020, 03:09:00 PM
Or put it in your log burner over night  ;)

Jo
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on January 27, 2020, 07:25:59 PM
Jo,
Unfortunately do not have a log burner, not even an open fire now.

Graham/Jo,
If its is annealed how does that effect the operations already carried out, e.g. its is already reamed out to 10mm for the crankshaft.

There is an outside possibility might have a kiln by end of day.  If that does occur I assume I could heat in kiln and then leave the kiln to cool down slowly (overnight) with the casting in it.

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Alyn Foundry on January 27, 2020, 07:58:32 PM
Hi Colin.

If you've got access to a kiln, all the better. Just take the parts up to around 800 degrees C, make sure of the colour and then just switch it off. Don't open the door until cold.

I say parts I'd do the crank web at the same time.

You might have to " squeak " the reamer through the 10 mm hole again, that's about all.

Cheers Graham.
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on January 27, 2020, 08:32:14 PM
Graham,

Funny you should mention the crank web, that also was a tad hard.

Missed out on kiln.  Must try harder (spend more  :ThumbsDown:

Good to know that is all that would be affected.

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on January 28, 2020, 06:07:04 PM
It was a bit of a struggle but eventually managed to find a cam.  As I had not sourced a kiln, I decided the only other way to get through the hard stuff was to remove it by brute force.

Cut out a paper pattern from Grahams plans, laid it on the cam disk and drew round the outline of the part which needed to be removed.  Used the 4" linisher to remove to within a couple of millimetres of the line.

Back on to the mill and used the boring head to bring to the correct shape/size.  For reasons best kept to myself this took an inordinate amount of time.   Decided to put a few holes in as per Jo's cam, did this using diving head and just indexing in 10 degeee steps.  Then drilled and tapped for 2BA fixing grub screw.

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Jo on January 28, 2020, 06:11:07 PM
A tipped tool will go through the hard stuff  :ThumbsUp:

Imitation is the greatest form of flattery  ;) I wonder which form of mechanism you are going to use to operate the shutter

Jo
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Alyn Foundry on January 28, 2020, 06:39:57 PM

I wonder which form of mechanism you are going to use to operate the shutter

Jo

I'm waiting to see a " springless " design appear....   ;) 
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Jasonb on January 28, 2020, 06:49:27 PM

I'm waiting to see a " springless " design appear....   ;)

Should be easy enough to machine a suitably shaped groove into the face of a disc for a follower to run in, couple of clicks and the CNC would have that done in no time :)

I suppose one advantage of these pre hardened cams is that you don't have to make them from silver steel and then heat treat to save wear :LittleDevil:
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on January 28, 2020, 07:15:24 PM
Jo,
I did like the way you had done your cam and the holes,  I just put mine a bit smaller and a couple more off them, so not quite plagiarism.

I also prefer the idea of positive lift of the cam follower and let weight help to close/shut the inlet port.  I think you commented that you had to fit a spring.  Would a heavier mechanism overcome that need.

Jason,
Pre-hardened  :lolb:

Not having CNC that option is out for me.  If I bought a CNC machine home I would be hung, drawn and quartered.

Perhaps you will have to modify your CHUKY and tried for grooved cam face and follower.

Graham,
Desmodronic valve timing on a flame licker  :Lol:

All,
Jo commented about using tipped tool to cut through the hard past of the casting,  I was able to do this on the Colchester with tipped tools but struggled on the Myford with tipped tools.  How would you fit a tipped tool to the boring head below:

Thanks all,

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Jo on January 28, 2020, 07:51:32 PM
How would you fit a tipped tool to the boring head below:

 ::)
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on January 28, 2020, 08:02:49 PM
Looks as though I'f better spend some more money then. :Lol:

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Alyn Foundry on January 28, 2020, 08:03:41 PM
 "   Graham,
          Desmodronic valve timing on a flame licker  :Lol:  "

Using high speed shutter and film....

Martins " Desmo " CHUK running at near 700 RPM.
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Jasonb on January 28, 2020, 08:04:24 PM
You can also use brazed carbide tooling, does not have to be replacable tip which can be reground for external cutting. Or if you want to use indexable holders then a simple adaptor can be knocked up to hold 6mm square shank lathe tools if you don't have the type of holder Jo shows.
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on January 28, 2020, 08:16:24 PM
Jo,.

Any recommendations as to manufacturer/supplier.  My boring head is for 5/8" bars or has sleeves down to 3/8".  I see Glanze do a set of 4.

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Jo on January 28, 2020, 08:20:00 PM
I have made a set of sleeves for my head and make use of what ever I can get at a good price. That is one of the Glanze ones but as we discussed earlier you will need to run the Mill head in reverse to use these to bore on the outside, which is not a problem for your very nice Automatic boring and Facing head  8)

Jo
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Jasonb on January 28, 2020, 08:47:14 PM
I have got the Glanze set of three 1/2" shank holders use them 90% of the time when using the boring head.

https://www.glanze.co.uk/product/set-of-3-1-2-dia-indexable-boring-bars/
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on January 28, 2020, 09:09:05 PM
JO,

My boring head is unfortunately threaded onto the R8 shank, so not sure it would stay in one piece if reversed.  Could always loctite it I suppose.

Just gone through all the bits I have with boring/facing head and found a couple of adaptors which will hold a tool at 45 degrees.  The bore is such that a 6mm shank indexable lathe tool will fit.

I had spotted those Jason.  They would all need the machine running in reverse to machine exterior surface?  Glanze do the set of 4 in either 1/2" or 3/8".  Looking at them one is a left hand tool so this would mean the mill could run in normal rotation with that one fitted.  Am I correct.?  Although the boring facing head has adaptors for 3/8"  I guess it would make sense to buy the 1/2" they would fit the industry standard 2" boring head and could be sleeved up to 5/8".

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on January 30, 2020, 07:20:08 PM
Decided to drill/tap the cylinder and drill clearance holes in base casting.  Due to the narrow band of material available I elected to tap for 4BA screws rather than 2BA and use 6 of them.  My DRO has the ability to do bolt circles.  I've never used this before so quick read of the manual and then set up for radius 27.5mm and 6 holes.  It was brilliant (as i'm sure a lot of you already know).  I was even more amazed when repeated the exercise for the base and the two bolted together. :cartwheel:

As the material I was waiting for did not arrive today, spent some time lapping the exhaust and inlet port faces then  moved onto making the Flap Valve and the Flap Valve Spring.  The spring was made from 10 thou shim and the valve from 15 thou shim.  First valve came out a bit too loose even though had followed given dimensions.  Remade it about 1mm wider all round and this appeared much better.  The spring does not have much spring in it. So a quick question to Graham/Jo.  Although made to dimensions I feel I need to shorten the legs slightly to allow them to move outwards and so give more spring.  Would I be correct. :headscratch:

Have loctited the bearing yoke to cylinder and this is now gently curing on a warm radiator.

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Alyn Foundry on January 30, 2020, 08:29:23 PM
Hi Colin.

I really like the fact that you've followed the drawing, the spring looks great.

It only needs to move a few " Thou " to work so will probably be fine. The important factor is that it keeps the disc lightly sealed to the lip on the cylinder.

Cheers Graham.
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on January 30, 2020, 09:00:27 PM
Graham,

Thanks for that.  When I loosely assembled cylinder on base with valve and spring i could not see any movement in valve, but having said that it was not bolted together only hand held so a bit awkward to test.  Will continue as is and see what eventually happens.

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on February 01, 2020, 09:13:35 PM
Yesterday whilst waiting for bits did a small job fro a friend of mine.  He wanted a lamp from a early 1900's  car modifying from candle power to mains power.

Quite pleased how it came out.

Little bit more today.  Minor slither off one edge of the crank web, shorten the crankshaft and loctite the pair together.  Drill and tap the flywheel 2BA.

The material I ws waiting for arrived and so could start on the arm and roller bearing for the inlet valve operation.

Next bits will be conrod and  linkages on the inlet valve.

Assemble bits so far and see what it looks like.

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Alyn Foundry on February 02, 2020, 11:33:36 AM
Good morning Colin.

JPEG 83 is showing promise!

                   ;)

Cheers Graham.
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on February 02, 2020, 08:12:04 PM
Thank you Graham,

As my material had arrived I could now make a start on the conrod.  I was going to use a piece if 10 x 4mm brass, this may be a good move it may not.

Marked it all out on surface place, 120mm between big end and little end centres and also lightly marked the midway point.

On to MYford in self-centre 4 jaw and centred the ends and then turned the shape down.  Narrowed the middle to 8mm for a distance of 10mm and then tapered each down to respective end. 1.4 degeee taper for big end and 2 degree taper to the little end.  Polished turned edges lightly when done.

Across to mill in vice on tall narrow parallel.  Set X-axis DRO to long centre line of rod, and set Y-axis DRO to the midpoint of the rod.  Started with big end and marked with stub drill then stepped up thorugh2mm to 7.5mm drills.  Swapped to miniature boring head to take to 7.96mm.  Set it to starting bore size so it just touched, started mill and raised the knee to strt cut.  Stopped very quickly when realised for some reason the cutter was cutting almost 8mm dia.  Reset and continued to 7.96mm  Bearings were supposedly 8mm but miked up at 9.97mm.  Moved to little end, drilled 2.8mm and put 3mm reamer through.

Read Grahams notes again and saw comment re make as light as possible.  So I put a series of holes down the center of the rod.  Then moved to BCA jig borer and rounded the ends off.

When done polished on some 1000 grot wet and  dry and then fitted bearing.  Cut a 3mm piece or rod and fitted rod to gudgeon pin boss.  All seamed ok so put piston on end, put it in the bore and used a 2BA screw to fit big end to crank web as a temporary measure.  It all spins nicely.

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Alyn Foundry on February 03, 2020, 11:51:04 AM
You're on the " home straight " now Colin!! :)
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on February 03, 2020, 12:24:55 PM
Completed conrod

Quick video showing it turns over.  Still needs big end pin and inlet valve and associated link.

Colin

yi6IHo-PPxs
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Alyn Foundry on February 03, 2020, 02:00:55 PM
That's running really freely Colin, excellent work!

You will have noticed from that demonstration that the piston wants to return to TDC thus aiding in the
" vacuum " part of the power stroke.

This is what made CHUK 2 the most effective of the three different engines.

Cheers Graham.
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on February 03, 2020, 11:27:45 PM
Was going quite well today.

Just prior to parting off the big end bolt I tried the crank web on it.  I  did it up just a little too hard and BANG :censored: :censored: :censored:  I split the casting at its weakest/thinnest point.

As it did not break completely I can at least still re-assemble everything and carry on making inlet valve bits until replacement casting (hopefully) appears.

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: crueby on February 04, 2020, 12:44:59 AM
Ouch!!




Would it be stronger to remake it from some flat steel bar, assuming that the casting was iron? Unless there is more shape I am not seeing on the other side...
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: cnr6400 on February 04, 2020, 01:05:37 AM
+1 on Chris' suggestion of flat mild steel (or stainless) bar / plate for the replacement crank piece.

 In my experience with cast iron you need some serious beef around the hole for press fits, because it is brittle. A piece of steel is very close to the weight of the iron and will take much more force in press fits before going tango uniform.

I'm sure when the bang happened you said "oh dear" or "son of a beach ball" or "that's awful" just like I would in my shop...... :embarassed:.......... (or wish I did)  :cussing:  Happens to all of us. Better luck tomorrow!  :cheers:
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Jasonb on February 04, 2020, 07:18:59 AM
Yes another vote for a steel replacement. There is not a lot of metal around that hole, may have got away with it if it were ductile iron but not that hard stuff. I made Chuky's one from round bar but flat would also do.

Infact Graham was thinking of getting some castings done for another engine and I suggested that he did not bother to do castings for a few of the simple parts much like this as it would save costs, risk of hardspots (hopefully not with new foundry) and actually be easier to work.
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Jo on February 04, 2020, 07:54:36 AM
I would check your casting I seem to recall something about the pin may be a little close to the edge  :noidea:

I cut my one out of a bit of steel rather than using the castings as the one I had was a little chilled (hard as glass) and I could increase the counter balance size  :)

Jo

 ::)
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on February 04, 2020, 09:46:22 AM
Thanks guys, these things happen.

Jo, you did warn me. I thought I would get away with it.  I think it was due to not enough undercut at the end of the thread and the slight taper as changed to the 4mm dia. forced the casting apart.  Oh well.. Live and learn.

Colin

PS, If I do use another casting at least by the end of today I will have collected a kiln in which to heat treat it.  :cartwheel:  Persuaded the other half she could perhaps have a go at decorative glass making.  Good excuse anyway.  :lolb:
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Alyn Foundry on February 04, 2020, 03:44:19 PM
Hi Colin.

There's a replacement crank web in the post, gone 1st Class, hopefully reach you tomorrow.

Cheers Graham.
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on February 04, 2020, 03:46:15 PM
Graham,

Many Thanks,

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on February 05, 2020, 11:18:32 PM
Graham,

Casting arrived.  many Thanks.

Think my machines are having a war with me.

None of my slitting saws fitted the 13mm arbor for the Aciera, had to borrow one of colleague of mine.  Manage to cut screwdriver slot on big end bolt.

Started to make the  small bits for the valve linkage.  Found I had forgotten to order the 6mm x 6mm brass bar.  Oh well make it out of a bigger piece.

Being as these are only little pieces decided to do them on the Cowells Mill.  This all went well till I fitted a 10mm dia end mill and did not turn the speed up enough.  Large POP and machine came to a halt.  Mains light lit but machine dead.
Quick call to Colin Childs at Cowells to find there is a 5amp fast blow fuse on the motherboard. Yes it had blown.  Luckily I have had a few bags of small fast blow fuses for the last 30 years and never used them, till now.  Fresh fuse and away it went again.  Put smaller cutter in and continued.

Moved to Cowells lathe with the piece of brass (newly fitted with M14x1 spindle) fitted self centering 4 jaw then went to drill with the tailstock.  For some reason it has locked solid, wont extend or retract.  Removed know of leadscrew and removed the tailstock, removed the grub screws and rear knob and the tailstock spindle slides out still with its operating screw thread.  Could not separate them by hand.  Ended up putting the plain shank of the screw part in collet chuck in Myford and used R8 collet chuck from the big mill to get enough grip to separate the two.  Got them apart, cannot get them to screw fully together.  The threads on the spindle look slightly rounded on the peaks.  Need to find out what thread it is and possibly run die down spindle and tap in the tailstock shaft.  That another job come to a halt.

Whats the secret to parting off brass.  Even though on centre it kept digging in and stalling machine


The only upside to the day is I now have a  Paragon SC2 kiln courtesy of Ebay. Another downside was my 98 year old father getting rushed to hospital after a fall at his care home, luckily no broken bones even though he did a forward roll out of his wheel chair.  Silly bugger took his feet of the footrest whilst he was being wheeled to his lunch and somersaulted from the chair.

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Jasonb on February 06, 2020, 07:15:54 AM
suspect you have imperial slitting saws with 1/2" holes.

Get a narrower parting tool, that is a wide cut for a small machine like a Cowells and the relatively "blunt" carbide inserts won't be helping. Either one of the 1.5mm HSS blades in a holder or something like the Mini-Thin inserts if you want to use carbide, I use one of their 1mm wide inserts for all my small parting and grooving.
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Jo on February 06, 2020, 07:30:40 AM
That Kiln looks rather nice Colin  8)

I assume this is a "new to you" Cowells and this is the first time you tried using the tailstock  :noidea: later machines are all metric threads...


The rake angle of the parting off tool is much "sharper" for parting off Brass. A Cowells will part off up to 2mm with the right tool but that is a massive width relative to the size of the lathe. I normally use hand ground HSS parting off tools on my Little C.

Jo
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on February 06, 2020, 09:24:26 AM
Jason/Jo Will sort out thinner hss parting tool. Will have a look at the minithins.  I do have a narrower hss parting tool but I think I need to remove the rake on the blade

Jo. No I have been using the machine (second user) for about 3 years. It suddenly went solid. It had been working quite happily 3 or 4 minutes earlier.

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Ian S C on February 06, 2020, 12:27:19 PM
It's possible to make a parting tool from a bit of all hard hacksaw blade, can't remember the thickness you can use either a power hacksaw blade, or hand type. With an all hard blade
take it easy, if it digs in it will go bang, just keep out of the line fire.
Ian S C
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on February 08, 2020, 05:31:06 PM
The inlet valve is made from a Stanley knife blade, with the edges ground off.  Ideal opportunity to use the Stent T&C.  The Stent needs quite a lot of TLC, but works quite well as a mini surface grinder.  Excuse the rudimentary wheel guard, its how it was when it came to me.

The little linkage parts for the valve were fun to machine and get the holes in the right places so as to keep free movement.  Then came the bit I was dreading.  My second ever foray into silver soldering.  The first attempt several weeks ago on a job for someone I abandoned and reverted to the oxy-acet rig.

When I did the cam follower end I milled a slot in the small block on the end, so I could push the two parts together to give myself a reasonable chance.  This worked ok.  The tiny link piece on the valve only has a solder area of 2mm x 6mm.  I knew I did not have enough hands, torch, solder, blade and link piece equals four hands, only having two caused a problem.  In the end I found some thin wire and threaded it through the holes and round the blade and twisted the end together,  It still move around a bit so made two more littel loops to go at right angles one either side of the link piece but about 10mm away.  Got it warm, flux melted touched it with solder which rad nicely but the piece moved about 1.5mm out of square.  B....r..   :censored: Got it hot again and when solder melted was able to push straight with a scriber.

Made 4mm  link rod with 4BA threads at each end.

Whilst this was going on I was testing the new kiln with the replacement crank web.  Warmed it up to 820 degrees Cent. let it soak for 30 mins and then switch off and allowed to cool for rest of afternoon.

Today I wanted to make the guide bracket for the link rod.  Scribed the shape I required onto a 6mm piece of brass and also scribed the radius of the bearing yoke to which it is to be fitted.  Milled the 4mm slot in it and then filed the bearing yoke radius.  Use the Die Filer for this.  Ended up with a pinched fingers a couple of times, but at least it all comes out square.  Once that was the correct shape, milled the rest to shape and drilled/counterbored for 6BA screws.

Tomorrows task is to try and fit it central and square to the bearing yoke.

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on February 08, 2020, 05:31:53 PM
Couple more pics.
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Jo on February 08, 2020, 05:56:23 PM
 :thinking: That reminds me of something  ;)

Jo
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on February 08, 2020, 06:06:21 PM
Thought it might.  Due to final location of the bearing housing I have had to put a washer between the housing and the cam follower lever.  Luckily I had parted off one of the bosses and have used that.  My guide has come out a little further than yours or so it looks.  I have a feeling that I might end up soldering a small washer to the link rod below the guide bracket and fitting a small spring from a biro or similar to aid in the lowering of the valve.  Just need to remake the crank web now, and possibly the lower link on the rod.  The walls are rather thin.

Trying to line the guide up and drill the holes in the bearing yoke will be entertaining.

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on February 10, 2020, 09:33:07 PM
Link rod drilled for split pin to support washer and hence spring to aid closing of valve.

Cylinder drilled for support/guide bracket.

Underside of base drilled to fit three small feet (when made).

New crank web appeared out of replacement casting.  Little bit more meat on this one, but still going to shorten the stroke by 1mm to leave a bit more meat on end of web. Piston will still just stick into the valve aperture, by about 0.5mm.
Scrappy drawings to check my dimensions. :)

Colin

Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Alyn Foundry on February 11, 2020, 10:53:40 AM
Good morning Colin.

If you're concerned about the same thing happening again why not reduce the thread size? There's little force on the crankpin anyway.

Alternatively a drilled and reamed hole with a locknut from behind. This method allows you to run the engine in either direction without the risk of the pin  unscrewing.

Cheers Graham.
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Jo on February 11, 2020, 11:34:48 AM
I would also suggest you slightly countersink the thread on the crankpin side so that the pin will go flush without having to over tighten it. (The threads nearest the pin will probably not be full depth which accounts for the force you needed last time  ;) )

Jo
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Jasonb on February 11, 2020, 01:15:46 PM
The alternative is to cut a run out groove at the base of the thread if you want the shoulder to sit nicely against the web. Works for die cut as well as screw cut threads

If not threading the hole you still want to chamfer the edge to ensure any internal radius left by the tip of the tool does not touch first.

(https://img.photobucket.com/albums/v156/jasonballamy/Engineering/Muncaster/DSC01259_zpsuy8wqlcy.jpg)
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Alyn Foundry on February 11, 2020, 03:51:57 PM
Jo and Jason.

Wise suggestions, from the seasond practitioners point of view, all done as a matter of course.

Cheers Graham.
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on February 11, 2020, 08:41:59 PM
Thanks, Jo, Jason and Graham.

When I made this one I did put an undercut at end of the thread.  I will see whether I can put little countersink in the crank.

Managed to make some feet for the base and get several coats of paint on the base, cylinder and flywheel.  I knew the cylinder paint was a matt finish, but nowhere on the can did it say the black enamel was a matt finish. Still it is what it is.  Im's sure once its been run (assuming it runs) it will get pretty sooty so maybe not so bad afterall.

Just need to shorten the 4BA fixing bolts for the base, shorten the bearing housing studs slightly, and shorten/find suitable grub screws for the flywheel and cam.

So it may look complete by tomorrow, other than flame generation system.

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Alyn Foundry on February 11, 2020, 09:19:17 PM
Hi Colin.

The Matt finish looks good to me.

It's always a good idea to cover the Iron with some form of protection prior to the " oily " stage as it ( the paint ) never seems to stay put afterwards.

Looking forward to seeing it run.

Cheers Graham.
Title: Re: CHUK2 - Alyn Foundry Flame Gulper - IT RUNS
Post by: Twizseven on February 13, 2020, 05:15:03 PM
Well its a runner - first ever.   :whoohoo: :whoohoo: :cartwheel: Thank you Graham for your assistance in this.

The paint said it needed to be cured, so each part went in kiln for 1hr in case of the matt black and 1.5hrs for the matt red.

2r4wGR8y1yc
Just needs its own flame generation system rather than propane torch.
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Kim on February 13, 2020, 05:28:34 PM
Very nice, Colin!   It runs great!  Now it's time for the happy dance!  :pinkelephant:
Kim
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on February 13, 2020, 05:30:40 PM
Thanks Kim,  I'm pleased its my first engine other than a pair of Elmers No.19.

I can start another set of castings now.

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: cnr6400 on February 13, 2020, 05:35:29 PM
 :ThumbsUp: :ThumbsUp: :ThumbsUp:
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Jasonb on February 13, 2020, 05:38:43 PM
Runs as good as it looks.

Interesting to see how changing the position of the torch will affect the speed.
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Jo on February 13, 2020, 05:52:02 PM
 8) Well done Colin

I can start another set of castings now.

Bitten by the bug   :lolb:  :pinkelephant:

Jo
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on February 13, 2020, 05:54:20 PM
Jason,

Thank you.  I have just had  another quick run and moving the flame around certainly make a tremendous difference to speed.

Will now see if I can make a meths burner for it.  Thinking of using an old copper plumbing bend (not sure whether its 1/2" or 3/4") and possibly putting three wick outlets.  Not sure whether this will provide enough heat.

If it is unlikely to work may have to revert to some form of gas flame device similar to yours.  What is your gas source?

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on February 13, 2020, 05:59:24 PM
Jo,

Thank you.

I have about 10 sets of castings in workshop. :)  Obviously compared to your stash this is miniscule. :LittleDevil:

I also have a GHT pillar tool to finish which I started about 10 years or so ago.  I also have a Stent T&C grinder which I bought about 8 years ago second hand.  It needs a good clean/paint and refurb and a few safety additions, such as a guard for the wheel.

A may fix these two first as they would be more useful going forward.

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Alyn Foundry on February 13, 2020, 06:17:42 PM
Well done Colin.

I've already shared your video with our group.

You'll find that a Yellow flame is much better suited for these engines in fact you could try covering the air holes on your torch initially.

I know Mike used a piece of 15mm Copper water pipe which he curved to suit the base diameter. He then Silver soldered a couple of smaller diameter tubes that carried a couple of wicks. He used Paraffin as a fuel because the Copper heats up rapidly and Methyated Spirit ends up coming out under pressure.

For gas operation the designs From Andy and Jason work really well, using either Propane or Butane neat
( without air ) gives a hot Yellow flame.

Cheers Graham.
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Jasonb on February 13, 2020, 06:24:19 PM
I just use a small camping gas type container and a cheap regulator both bought on e-bay. You can see it at the end of the video

YFk4ZhEA4kE
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on February 13, 2020, 07:21:28 PM
Jason,

I've got several of those cylinders, so just ordered a adaptor/regulator.

Graham,
Not sure why I said Meths, I actually meant paraffin.

See whether can get my silver soldering to hold fluid in rather than just hold things together. :Lol:

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Admiral_dk on February 13, 2020, 10:45:45 PM
Congratulations - you have a great runner with good looks  :praise2:   :cheers:

Now another burner that isn't louder than the engine will be a big bonus  ;)

Per
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Flyboy Jim on February 14, 2020, 03:45:02 AM
A great runner Jason.  :ThumbsUp:

I've got a flame gulper of some sort on my bucket list, but I don't think they're as easy to make and get running as you make it look.  :praise2:

Jim
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Zephyrin on February 14, 2020, 09:10:39 AM
great runners, these 2 flame gulpers...
awesome and attractive model too
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on March 30, 2020, 02:41:55 PM
Finally managed to make gas burner.  This took several attempts.  The first attempt at silver soldering failed (miserably).  It looked quite good at first.  The end of the tube had sealed, had nice joint round base of pipe to the larger diameter connector.  Till I spotted the fact that was not immediately apparent.  The pipe had slid down inside the larger body by just over an inch.  Only spotted this when lifted of the soft fluffy heat mat I had been using.  Tried to reheat to melt the solder so I could slide the thin tube up a bit.  It would not heat up enough even with the big burner on the torch.  Oh well back to the drawing board and make another set.  This time the larger component was made couple of mm longer and the central bore smaller so pipe could no longer slide through.  Success this time.

It does not run a quickly as it did on the big propane burner.  Currently using Jasons design of gas pipe with 5 holes (0.52mm dia) at 4mm distance from each other.  Wondering whether to add a further two holes to give a slight bigger flame.  Any thoughts on this??  Couple of times the flame was blown out as piston came back down bore.

See video below.
_gwCVr1dBA8
Colin

Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Jasonb on March 30, 2020, 04:50:41 PM
I can't hear the valve opening, is the engine sitting flat on the bench and not allowing the exhaust to escape? That would reduce the blowback coming out of the inlet
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Alyn Foundry on March 30, 2020, 05:19:36 PM
Hi Colin.

That's a nice job on the burner.   :ThumbsUp:

I'm thinking that you need another couple of holes along the length as the whole port doesn't seem to be covered.

Cheers Graham.
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on March 30, 2020, 05:44:46 PM
Jason,
The metal base is clear of the wooden plinth by around 6mm.  Nothing has changed since I ran it with the big propane burner.  I am assuming as it ran reasonably well the exhaust is opening.  THis was always something I was unsure about as the exhaust spring and valve do not have a huge amount of space to move around in.

Graham,
I'm afraid the burner is pretty well a copy of Jason's.  The first camping gas adaptor I purchased although it showed hose and connector in advert it did not come with one and they decided they could not supply one.  Ordered another with hose but this time it came with a big adaptor for a large propane tank.  I had to make my own push in adaptor which has three 5.1mm dia 'O' rings to seal it into the end of the flame tube assembly.  Same number of holes but in my case 0.52mm dia as did not have a 0.5mm.  I think to put a flame across the full width it will need two extra holes (possibly three) as a minimum.

It certainly will run quite slowly.

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Jasonb on March 30, 2020, 06:15:07 PM
Don't forget mine was for a 24mm bore version so you may need the extra holes as Graham says plus play about with flame size (gas flow) and position.
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on March 30, 2020, 08:35:10 PM
Jason,

Another 4 holes has made it a lot better.  Trouble is I've just run out of gas.  I think I've had the canister for around 30 years.  Not going to  get another one in near future.

Colin
Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Bluechip on March 31, 2020, 08:49:43 AM
Jason,

Trouble is I've just run out of gas.  I think I've had the canister for around 30 years.  Not going to  get another one in near future.

Colin

I don't know what gas you use but CPC stock some of them and are still delivering.
( I have a delivery from them coming by UPS today ).

https://cpc.farnell.com/c/tools-maintenance/cleaning-chemicals/workshop-chemicals

Dave

Title: Re: CHUK2 - Alyn Foundry Flame Gulper
Post by: Twizseven on March 31, 2020, 10:30:25 PM
Dave,

Thanks for that.  Spare cans just ordered.

Hope you are keeping well.

Best Regards,

Colin