Model Engine Maker

Engines => From Kits/Castings => Topic started by: RayW on January 19, 2022, 03:30:31 PM

Title: Alyn Foundry CHUK 2
Post by: RayW on January 19, 2022, 03:30:31 PM
Graham has very kindly supplied me with a set of CHUK 2 castings for my next project. The build will definitely be interesting, as there are no detailed drawings, just 10 pages of Graham's handwritten notes and sketches.
I have been reading and re-reading the various build threads here, but if anyone who has already built a CHUK 2 has any helpful tips or suggestions, they will be very welcome.
I do not intend to make this a detailed step by step build thread as that has already been done before, but I will make progress reports from time to time, as various milestones are reached.
Title: Re: Alyn Foundry CHUK 2
Post by: Jo on January 19, 2022, 06:03:22 PM
Nice castings  :pinkelephant:

Jo
Title: Re: Alyn Foundry CHUK 2
Post by: Jasonb on January 19, 2022, 07:37:03 PM
Yes hopefully all from the new foundry so they should be nice on the inside too ;)

Title: Re: Alyn Foundry CHUK 2
Post by: Twizseven on January 19, 2022, 09:22:22 PM
I note the bearing housing has Grahams latest pretty top.

Colin
Title: Re: Alyn Foundry CHUK 2
Post by: Alyn Foundry on January 20, 2022, 12:26:27 PM
Glad to read they arrived in good shape Ray.

Yes, they’re nice castings, all done at the new Iron foundry. The bearing housing and top were done by the Brass foundry I’ve used for over 30 years, now run by daughter and son-in-law.

Here’s a picture of one I built last year, stripped down for cleaning.

Cheers Graham.
Title: Re: Alyn Foundry CHUK 2
Post by: RayW on January 21, 2022, 03:11:33 PM
Do I assume, Graham, that the brass bearing housing cap serves no actual practical purpose and could simply be glued in place?
Title: Re: Alyn Foundry CHUK 2
Post by: Alyn Foundry on January 21, 2022, 03:56:21 PM
Good afternoon Ray.

Of all the vintage engines in my collection the Barker “ B “ type is my favourite where the Brass works are concerned. The Pagoda style top finishes off the oil boxes beautifully. So yes, it’s merely a purely cosmetic feature and will hide the two Allen screws that hold down the bearing housing to the pedestal.

CHUK 2 has been evolving since its development over 20 years ago.

I still have a few sets of castings available for this model.  If anyone is interested, please drop me a PM.

Cheers Graham.
Title: Re: Alyn Foundry CHUK 2
Post by: RayW on January 21, 2022, 08:44:54 PM
The new foundry certainly seems to be producing some nice castings. Lets hope they machine as well as they look. The only minor blemishes I have noticed were on some of the fins, where the metal has not quite filled the mould, and one small blow hole in the central boss of the flywheel. All easily rectified with good old JB Weld!
Title: Re: Alyn Foundry CHUK 2
Post by: RayW on February 10, 2022, 12:35:42 PM
Base and cylinder have now been machined, and the bore honed and polished to a good finish. The flame port slot has also been milled. A shallow double boss has been machined on the base of the cylinder, the larger diameter locating the cylinder on the base casting, and the small diameter being lapped to provide a flat surface against which the flap valve will seal.
I have opted not to machine the cylinder fins as I prefer to retain the cast look.
Title: Re: Alyn Foundry CHUK 2
Post by: Jo on February 10, 2022, 04:09:26 PM
Coming along nicely  :)

Jo
Title: Re: Alyn Foundry CHUK 2
Post by: Alyn Foundry on February 11, 2022, 01:05:19 PM
Your cylinder finish is excellent Ray.

 :cheers: Graham.
Title: Re: Alyn Foundry CHUK 2
Post by: RayW on February 21, 2022, 04:47:02 PM
All the main castings have now been machined, with the pedestal having been secured to the cylinder with Loctite 648. The flame port face has been lapped to a mirror finish to provide a good sealing face for the shutter.

Now time to move on to the "fiddly bits", ie the shutter and operating mechanism, and the flap valve and spring. There are a few rough areas and holes on the flywheel that will require a bit of fettling with body filler before painting. I have left quite long bosses on the flywheel, crank web, and cam at this stage until I see exactly where each of them need to be positioned. The crankshaft will also be cut to length, and the crank web attached with Loctite.
Title: Re: Alyn Foundry CHUK 2
Post by: Alyn Foundry on February 21, 2022, 08:58:19 PM
Nearing the home straight now Ray….

 :cheers:  Graham.
Title: Re: Alyn Foundry CHUK 2
Post by: RayW on February 21, 2022, 09:15:11 PM
Just remembered, a con rod would also be useful!
Title: Re: Alyn Foundry CHUK 2
Post by: RayW on March 02, 2022, 04:09:20 PM
Continued progress, with all major components now completed. The con rod is waiting for the little end to be added once I get the bearing that is on order. The shutter mechanism works well, with a ball race serving as the cam follower, and a lapped Stanley knife blade as the shutter. The flap valve, which locates in the base casting, is made and just needs lapping to ensure a good seal with the base of the cylinder.
I am following Grahams idea of three coil springs to support the valve, with the springs each being located in a recess in the base.
Title: Re: Alyn Foundry CHUK 2
Post by: Admiral_dk on March 02, 2022, 04:14:52 PM
Looks good and so close to first POP  :ThumbsUp:

 :popcorn:    :cheers:

Per
Title: Re: Alyn Foundry CHUK 2
Post by: Alyn Foundry on March 03, 2022, 11:48:00 AM
Good morning Ray.
 
As Per wrote, you’re nearly there now.

I’m just wondering if you’re relying upon the weight in the cam follower to shut the port or do you have a spring hidden somewhere?  ;)

 :cheers:  Graham.
Title: Re: Alyn Foundry CHUK 2
Post by: RayW on March 03, 2022, 05:13:04 PM
The brass bar that the cam follower is mounted on is heavy enough without spring assistance and closes the shutter well Graham.
Just received the small springs for the exhaust flap valve today, but, frustratingly, the little end bearing which was due to arrive Monday or Tuesday has still not arrived.
Title: Re: Alyn Foundry CHUK 2
Post by: Alyn Foundry on March 03, 2022, 07:00:46 PM
I too am eagerly awaiting a very late 1st class package Ray.

Royal “ snail “ are definitely living up to their name these days….
Title: Re: Alyn Foundry CHUK 2
Post by: Jasonb on March 03, 2022, 07:27:56 PM
It's almost there Ray and looking good, the brass ring around the top of the cylinder will add a bit of colour.

Hope you both get your post soon.
Title: Re: Alyn Foundry CHUK 2
Post by: RayW on March 15, 2022, 05:41:53 PM
Fitted the three springs that support the flap valve in the base today but not getting any compression or vacuum, so either the flap valve or the flame port shutter (or both) are not sealing. Despite this, it actually ran using the paint stripper nozzle on my gas torch.
Here is a short video of the first two runs.
Qq0_wqlf4yA
It continued to start and run until it got too hot.
Sorry, didn't take any photos of the springs in the base. Will do so when I dismantle later on.
Title: Re: Alyn Foundry CHUK 2
Post by: Alyn Foundry on March 15, 2022, 05:56:55 PM
It’s a runner, well done Ray.   :ThumbsUp:

You might find that having the base raised by some little feet will help the exhaust process and get the characteristic Raspberry.

 :cheers: Graham.
Title: Re: Alyn Foundry CHUK 2
Post by: Jo on March 15, 2022, 06:12:34 PM
Nice, well done Ray.  8)

Jo
Title: Re: Alyn Foundry CHUK 2
Post by: Jasonb on March 15, 2022, 06:15:49 PM
Good to see it running Ray

You tend to only feel compression when you turn them backwards, when going forwards there is just a little resistance as it quacks.
Title: Re: Alyn Foundry CHUK 2
Post by: crueby on March 15, 2022, 06:41:19 PM
Great!  :ThumbsUp: :ThumbsUp:
Title: Re: Alyn Foundry CHUK 2
Post by: Roger B on March 15, 2022, 06:57:47 PM
Excellent  :ThumbsUp:  :ThumbsUp:
Title: Re: Alyn Foundry CHUK 2
Post by: RayW on March 15, 2022, 07:11:51 PM
Thanks all for your comments.Yes Graham, I do still need to make some feet. I recycled a stainless steel rally plaque for the flap valve in the base, so perhaps that is why it's not 'quacking". As I said Jason, there is no resistance in either direction so I will re-lap the flap valve and the flame shutter to try and improve things.
I have also found that the shutter is sometimes catching on the bottom edge of the flame port as it closes, so I am wondering if it has bowed slightly. I may also add a small spring to ensure that the cam follower stays in close contact with the cam.
Title: Re: Alyn Foundry CHUK 2
Post by: Admiral_dk on March 15, 2022, 10:35:49 PM
I bet that was a very satisfactory feeling when it came to life  :ThumbsUp:

Great first runs  :cheers:

Per
Title: Re: Alyn Foundry CHUK 2
Post by: RayW on March 17, 2022, 09:24:08 PM
Made a couple of small tweaks and it is now running much better and quieter. I realised that the cam follower was bouncing slightly and making a knocking noise, so I have added a small tension spring to keep the follower in constant contact with the cam. The addition of a small screw in the rod guide to locate the bottom end of the spring has also enabled me to finely adjust tension on the rod, giving a better contact between the flame port and the shutter. This has resulted in the CHUK (duck) finding its characteristic quack.
I have found that an occasional squirt of WD40 into the cylinder ( with the flame extinguished), greatly assists the free running, if leading to a rather smoky workshop!
This is the video of the modified engine:
8YvOZs4g3SM
Title: Re: Alyn Foundry CHUK 2
Post by: Jasonb on March 18, 2022, 07:21:16 AM
That's running well now :)
Title: Re: Alyn Foundry CHUK 2
Post by: Alyn Foundry on March 18, 2022, 11:59:58 AM
Well done Ray, a great improvement.   :ThumbsUp:

 :cheers: Graham.
Title: Re: Alyn Foundry CHUK 2
Post by: RayW on April 01, 2022, 02:12:47 PM
The three main castings (base, cylinder and bearing carrier) were painted in in Graphite Grey Very High Temperature paint and cured in the oven for about an hour. The flywheel and lettering on the base were brush painted with Hammerite Smooth Red paint.

I am now looking into various designs of gas burner, ideally to give a clean blue flame similar to the blow torch I have been using up to now, rather than a sooty yellow one.
Title: Re: Alyn Foundry CHUK 2
Post by: wagnmkr on April 01, 2022, 02:17:39 PM
I like the colour combination.
Title: Re: Alyn Foundry CHUK 2
Post by: Alyn Foundry on April 01, 2022, 03:54:33 PM
Very nicely done Ray….

CHUCK 2 doesn’t really lend itself well to any form of burner, I’ll be interested to see what you might come up with.

 :cheers: Graham.
Title: Re: Alyn Foundry CHUK 2
Post by: Admiral_dk on April 01, 2022, 04:49:55 PM
Great paint job  :ThumbsUp:

I hope it runs just as well now you got it re-assembled  :cheers:

Per