Author Topic: CONWAY 0-4-0 3 1/2" GAUGE LOCO  (Read 174340 times)

Offline Firebird

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #960 on: September 15, 2019, 09:21:34 AM »
Hi

Thanks for the thumbs up cnr6400

Heres a photo of all the parts



I have a block of bronze that is big enough to make the body but before I attack it I need to note down a few refinements and an easier way of machining

Cheers

Rich

Offline doubletop

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #961 on: September 15, 2019, 09:29:41 AM »
Rich

Great work; but there's no hiding when you post full size photo's from your n-megapixel camera. You may want to try re-sizing them

https://www.faststone.org/FSResizerDetail.htm

I find 1024 x 768 is large enough for these forums.

Pete
?To achieve anything in this game, you must be prepared to dabble on the boundary of disaster.? - Stirling Moss

Offline Firebird

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #962 on: September 15, 2019, 09:40:20 AM »
Hi

Thanks Pete

I'm using Imgur now. I have clicked on the auto resize button for 640 x 480???

I'll go back and look into it :ThumbsUp:

Cheers

Rich

Offline Firebird

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #963 on: September 15, 2019, 09:52:33 AM »
Hi

Resized to 640 x 480




Offline Firebird

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #964 on: September 15, 2019, 09:55:02 AM »
Hi

Looks clear enough. I think I can only resize one photo at a time on the Imgur site so I will investigate your link Pete

Cheers

Rich

Offline Firebird

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #965 on: September 15, 2019, 10:15:38 AM »

Offline doubletop

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #966 on: September 15, 2019, 10:34:19 AM »
Rich

I use Imgur but resize and watermark my photos with Faststone, a bit of habit from the old days before we all had to move off photosuckit. I've just had a look at imgur and you can resize to 1024x768. What is more it looks like you can re-size images that have already been saved. So you could scale up/down the large images you have already posted on the forum.

In Imgur select the image and 'edit'. top left resize/crop. Top right edit the values in the size window. Try making your recent 640 x480 image 1024 x 768 and see what happens

(EDIT - it looks like you've done that as the resized image in post 207072 is also re-sized in post 207069. Just need t go back and do the images in the earlier posts.)

Pete
« Last Edit: September 15, 2019, 10:56:42 AM by doubletop »
?To achieve anything in this game, you must be prepared to dabble on the boundary of disaster.? - Stirling Moss

Offline doubletop

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #967 on: September 15, 2019, 09:02:06 PM »
Rich

It appears you've sorted the image problem, I'll now join in the regulator debate.

Stroudley regulators have always been a problem and the solution for testing has been blanking off the dry side of the superheaters. That then creates a problem because the superheater then becomes part of the certification of the boiler under test. Our boiler inspectors are not happy with that, particullarly when the superheater has a silver soldered stainless to copper transition, as yours does. Apparently the joint can be subject to failure, so it is up to the inspectors whether they are prepared accept that approach or not.

In my case I couldn't get the Stroudley on my Dart to seal very well. At full boiler pressure I had the loco trying to creep when I put it into gear with the regulator shut so had to do something about it. I went the ball valve route and fabricated a ball valve 'Stroudley'





Fortuanately the Dart is 7.25" gauge and has a large steam dome so I was able to get it all in



Be aware that many ball valves are plated brass so make sure you get a stainless valve. You'll notice that the two valves are different in the photos above. The top one is brass the other is stainless. Stainless valves are available, for example.

https://www.anzor.co.nz/ball-valves

Check the bore of the ball, some can be too small to allow adequate steam flow.

These valves have ptfe seals that swell up in use so can make operation quite stiff when running. My valve can be dissassembled so I took the seals out and removed a few thou from the back of both of them. Ptfe machines quite well so a skim with a sharp tool was quite easy.

Hope that helps

Pete

« Last Edit: September 15, 2019, 09:08:44 PM by doubletop »
?To achieve anything in this game, you must be prepared to dabble on the boundary of disaster.? - Stirling Moss

Offline Firebird

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #968 on: September 18, 2019, 07:02:07 PM »
Hi Pete

Very helpful indeed  :ThumbsUp: :ThumbsUp: :ThumbsUp:

Cheers

Rich

Offline Firebird

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #969 on: September 21, 2019, 10:26:26 AM »
Hi

Not much to report I'm afraid  :(

The valve I have designed I'm fairly confident will work but now I have seen Petes idea of the stroudley ball valve I am wondering if I can get that to fit  :thinking:

I have ordered some stainless steel ball valves so will have to wait until they arrive before any more progress can be made

Cheers

Rich

Offline Firebird

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #970 on: September 29, 2019, 04:37:42 PM »
Hi

Well there has been quite a lot fiddling and fettling going on in the background. The valve I designed will work I think but I decided the ball valve idea might be better. One was ordered and has now arrived.

As before I have mocked one up using bits of scrap ally and brass before wasting expensive bronze.

Heres the block and an adapter. The block is tapped 3/8" x 32 and the adapter has a 1/4" BSP thread to suit the ball valve



Its a bit of a tight fit but just goe's in



A lever from a bit of stainless steel bar





It was an absolute  :cussing: to machine, really hard

Shame I machined the central slot wrongly  :facepalm:

It should have been at a 45° angle  :wallbang:

This time I machined a bit of stainless 303 1/2" round bar down to a 1/8" flat piece and made the new one from that.

After drilling 3 holes, the 2 outer ones 2.5mm for tapping M3 and the centre one 1/8" I mounted it on a bit of ally and turned it through 45°





Machined away some waste







The little stop lug on the valve body is machined away



A trial fit. I have made a new adapter around 1" long



So far it all still fits inside the inner dome



Another lever with the same outer hole centres from stainless steel but with a 1/8" square hole in the centre





Thats it so far

Cheers

Rich



Online Kim

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #971 on: September 29, 2019, 05:52:52 PM »
Nice looking progress Rich!
Kim

Offline Admiral_dk

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #972 on: September 29, 2019, 07:33:46 PM »
Great to see that you seems to have found a working solution that should last too  :praise2:
I hope this will bring your build back on track again  :cheers:    :popcorn:

Offline cnr6400

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #973 on: September 29, 2019, 08:13:09 PM »
That's looking great Rich!  :ThumbsUp: :ThumbsUp: :ThumbsUp: :popcorn: :popcorn: :popcorn:

 The only thing I would ask - are the valve and the pipe piece it sits on locked rotationally? if they ever loosen and rotate while running due to heat and vibration, it could bind the linkage. Maybe a "lock block" between valve and anchor block, pinned to both during or after assy, might work to prevent any rotation. Just food for thought.
"I've cut that stock three times, and it's still too short!"

Offline Firebird

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #974 on: September 29, 2019, 08:33:30 PM »
Hi

Thanks kim and admiral  :ThumbsUp:

cnr6400, I was planning to use loctite assembly on the threads.

Cheers

Rich

 

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