Author Topic: CONWAY 0-4-0 3 1/2" GAUGE LOCO  (Read 174203 times)

Offline Jasonb

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #270 on: November 11, 2017, 10:19:24 AM »
There are two types of dezincification, one caused by hight temps while soldering and the other during use.

It is the hot water that affects the zinc in brass due to impurities in the water, steam is pure so won't have an effect so general rule of thumb is if below water line use bronze but brass can be used above though items very close that may get some carry over if the engine primes or is on rough ground are better off in bronze. So things like manifolds, water gauges, clacks, etc are best in Bronze or GM

Online Jo

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #271 on: November 11, 2017, 11:16:32 AM »
Anything that screws or bolts in can be made of brass because they are easily replaceable.

This one was not replaced in time.

Luckily it failed when no one had their head in the cab shovelling coal  :paranoia:

Jo
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Offline Firebird

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #272 on: November 11, 2017, 12:35:56 PM »
Hi

Of course gun metal or bronze castings are preferred if available.

On the plans such things as the inner dome etc are specified as brass and to save time I have bought commercial blower valve, safety valve, clacks, water gauge etc and all are brass.

Cheers

Rich

Offline Jasonb

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #273 on: November 11, 2017, 01:22:58 PM »
Don't have to be castings, you can buy bronze and GM barstock

At the time the Conway was described they were still using sifbronze on boilers which you can't use now as that also fails.

Blower and safety should be OK as they mainly see steam, bottom fitting a water gauge would be better in bronze and many commercially made ones are

Offline Firebird

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #274 on: November 12, 2017, 09:00:05 AM »
Hi

A quick update




Cheers

Rich

Offline Firebird

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #275 on: November 16, 2017, 11:35:38 AM »
Hi

Some good news

Julian took our boilers, his Simplex and my Conway, to the club inspector for inspection and both have passed.

 :whoohoo:  :wine1: :cheers: :DrinkPint: :ROFL: ;D

Cheers

Rich

Online Jo

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #276 on: November 16, 2017, 11:57:40 AM »
 8) 

Jo & :pinkelephant:  ::)
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Offline b.lindsey

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #277 on: November 16, 2017, 12:41:08 PM »
That is great news Rich...nothing holding you back now :)

Bill

Offline Firebird

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #278 on: November 18, 2017, 07:57:52 PM »
Hi

Thanks Jo and Bill  :ThumbsUp:

Now that the boiler has passed its visual inspection I can carry on with it.

The firehole is made from a piece of thick walled (1/8") 1 3/4" copper tube. Each end is turned down to fit between the firebox rear plate and the backhead.





Silver solder into the firebox first.



Cheers

Rich

Offline Firebird

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #279 on: November 18, 2017, 08:07:02 PM »
Hi

After each soldering job it has to go back in the pickle so I am using the time to make up a few bits and pieces.

This is a little jig which will hopefully hold the 2 water gauge bushes in alignment when I silver solder them into the backhead.

Each vertical piece is threaded 1/4" x 40tpi. Drilled and tapped 3mm and cross drilled 5/32" for the stainless steel rod.



Cheers

Rich

Offline Firebird

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #280 on: November 18, 2017, 08:47:46 PM »
Hi

The axle driven water feed pump.



I am going to fabricate it  :thinking:

The bottom connection which is the water inlet. Turn a bit of 1/2" square brass and screw cut 3/8" x 40tpi. Drill and tap 3/8" x 32tpi. The plans specify 3/8" 26tpi but I already have some union nuts 3/8" x 32 hence the change



While the lathe is set up for 32 and 40 tpi I have screw cut several lengths of brass in a variety of diameters.



In the lathe drill through, use a centre drill to create the cone (centre drills are 60°) and part off. Screw into the connector and silver solder in.



The valve body I am using some 5/8" square brass and piston body some 5/8" round brass.

The valve body in the lathe drilled and tapped 3/8" x 40tpi. One end has to have a flat bottomed hole which I did with an end mill. In the centre of the body I have drilled and tapped 1/2" x 40tpi





The 5/8" piston body has been turned down to 1/2" for 1/8" and screw cut 1/2" x 40tpi. Drilled through and reamed 3/8"



Screw the 2 pieces together



And silver solder




Cheers

Rich

Offline Steamer5

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #281 on: November 18, 2017, 11:39:17 PM »
Hi Rich,
 The boiler is coming on nicely! I bet you are please it pass inspection! Just a comment re fusible plugs, it looks like you don’t have one, I was in a discussion last weekend about these. We are starting to see Duplex boilers being built here & the inspector that passed the boiler was hot on the need to have a fuseable plug. I haven’t got a copy of the code, & it’s currently under review, but it apppears that they are a requirement not only in Duplex but steel (again). Seem to remember that they were always installed in copper as well, but just sort of vanished. Anybody got any info as to why, or as usual did I miss something?

Cheers Kerrin
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Offline Kim

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #282 on: November 19, 2017, 06:10:09 AM »
Hi Rich,
The boiler is looking really good, as does pump!
You're making great progress here!

Kim

Offline Jasonb

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #283 on: November 19, 2017, 07:56:15 AM »
Looking good Rich, on other fabrications you may find it better to do any reaming after soldering as there is a risk of parts distorting slightly due to the heat.

Fusable plugs are not required here by code and are rare on copper boilers particularly in these sizes. You do see them on most steel boilers and some larger copper ones.

Offline Firebird

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Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #284 on: November 19, 2017, 01:28:15 PM »
Hi

Thanks Kerrin, Kim and Jason.

Jason, the bit of 3/8" stainless round I have is a bit tight in the reamed bore so will need some polishing in.

The back head and fire hole have been silver soldered in



There is still a lot of work/soldering to do on the back head, stays/bushes/foundation ring etc, too much to do in one go so I have started with 17 stays.

Ready to be soldered inside the firebox



After silver soldering



Its back in the pickle again now. I might not get a chance to touch it again untill next week.

Cheers

Rich

 

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