Author Topic: CONWAY 0-4-0 3 1/2" GAUGE LOCO  (Read 174254 times)

Offline Firebird

  • Full Member
  • ****
  • Posts: 1328
  • East Midlands UK
Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #240 on: October 07, 2017, 06:39:53 PM »
Hi

Thanks Jason  :ThumbsUp:

Julian has emailed our club boiler inspector for clarification, we await his reply.

5/32" (which is near enough 4BA) copper rivets are available at a reasonable price. As far as I can see I need 77 stays so using copper rivets would save an awful lot of work.

Cheers

Rich

Offline Firebird

  • Full Member
  • ****
  • Posts: 1328
  • East Midlands UK
Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #241 on: October 07, 2017, 08:07:57 PM »
Hi

A bit of everything today starting with turning the flange for the inner dome.




In the rotary table to have 8 holes drilled




Silver solder 2 parts together



Make a blanking plate to be used when the boiler is ready for its hydraulic test



On a different track, if you'll pardon the pun ::)

I made up some holders to use the 4"-6" leftovers of silver solder



The tubes have closed up a bit, probably due to repeated heating operations, so I have gently teased them apart and fitted the smoke box tube plate to straighten them out



The tubes are slid into the boiler barrel





I have made up some small screws threaded 1/8 x 40 from phospher bronze rod and temporarily fitted the backhead





The rest of the afternoon was spent jiggling about trying to find the best fit. A lot of things to line up, the firehole, the solid stay and blower tube that go from front to back etc etc. then start to make up the foundation ring.







Cheers

Rich


 




Online Jasonb

  • Full Member
  • *****
  • Posts: 9463
  • Surrey, UK
Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #242 on: October 07, 2017, 08:09:42 PM »
Rich, it's the core dia that matters so 1/8 "rivit should be fine as a substitute for 4BA

Offline Firebird

  • Full Member
  • ****
  • Posts: 1328
  • East Midlands UK
Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #243 on: October 07, 2017, 08:45:18 PM »
Hi Jason

Yes of course 1/8" :facepalm: :Doh: :facepalm2: :old:

Cheers

Rich

Offline crueby

  • Full Member
  • *****
  • Posts: 18554
  • Rochester NY
Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #244 on: October 07, 2017, 11:25:23 PM »
Boiler is looking great!


 :popcorn:

Offline Firebird

  • Full Member
  • ****
  • Posts: 1328
  • East Midlands UK
Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #245 on: October 08, 2017, 05:46:01 PM »
Hi

Thanks Crueby :ThumbsUp:

Some more juggling today trying to get things aligned. It is mentioned in the article that the blower pipe and solid stay are very tight. You are not kidding :facepalm:. Hindsight being a wonderful thing and all that, I would have moved a couple of the bushes by a fraction if I had known. Why he had to make things so tight I don't know  :shrug: Anyway these things are sent to challenge us.

I have made up a couple of dummy bushes from brass for the smoke box end. I have just drilled them through 1/4". The phospher bronze bushes must be tapped and the stay and blower pipe threaded



They fit ok

At the other end I made up a dummy firehole from ally and clamped the firebox in the best position I could get



The solid stay and the blower tube will come through the holes in the back head but I can't get them cental enough to fit bushes



I have overcome the solid stay problem by making an offset bush, here being drilled in the mill



Back in the lathe, turn and part off



OK that one fits  :cartwheel: but the blower tube is still out. There is more room on that side of the back head so I am going to enlarge the hole, make a larger bush with hole for the blower tube offset which will hopefully resolve the problem



Finally today a bit of work on the foundation ring




Cheers

Rich




Offline 10KPete

  • Full Member
  • ****
  • Posts: 1606
  • Nordland, WA, USA
Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #246 on: October 08, 2017, 07:49:18 PM »
Rich, can you not put a slight 'S' bend in the blower tube to get it to center in the bushing??

Pete
Craftsman, Tinkerer, Curious Person.
Retired, finally!
SB 10K lathe, Benchmaster mill. And stuff.

Offline Firebird

  • Full Member
  • ****
  • Posts: 1328
  • East Midlands UK
Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #247 on: October 08, 2017, 08:15:00 PM »
Hi Pete

The blower tube and the solid stay run across the top of the inner firebox in between the crown stays. The back of the inner firebox is only 3/8" from the backhead. If you look about 5 photos back you can just see the top of the firebox. There is not enough room to put an S bend in.

Cheers

Rich

Offline 10KPete

  • Full Member
  • ****
  • Posts: 1606
  • Nordland, WA, USA
Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #248 on: October 08, 2017, 08:19:46 PM »
Ouch! I didn't realize it was so tight!!! Looking at the pic again I do see the firebox....

Pete
Craftsman, Tinkerer, Curious Person.
Retired, finally!
SB 10K lathe, Benchmaster mill. And stuff.

Offline Florian Eberhard

  • Full Member
  • ****
  • Posts: 437
Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #249 on: October 08, 2017, 09:27:50 PM »

I made up some holders to use the 4"-6" leftovers of silver solder



 

Hi Rich

I usually solder that leftover piece onto the next rod to use it without any leftover (which would only happen if you have one bar left)

I apply a little flux on the end of both bars, then use a small point gas torch to heat the two rods carefully (placed on some fire brick and with a small gap between them)
As soon as they start to melt, I join them and remove the flame of the torch. Works pretty well for thin rods and lets you use your silver solder with no leftover.

Florian

Offline Firebird

  • Full Member
  • ****
  • Posts: 1328
  • East Midlands UK
Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #250 on: October 12, 2017, 08:24:58 PM »
Hi

I have tried that Florian but without success, I just end up with molten blobs :shrug:

I have knocked up a dummy offset bush for the blower tube



The hole in the backhead has been enlarged to 5/8"



The tube fits freely now



Set up in the brazing hearth to silver solder the front part of the foundation ring. A turbo torch puts some heat into it



Then in with the oxy pro/propane to get up to temperature for soldering



After soldering





The front end is drilled and tapped 1/8 x 40 in 3 places through the barrel and into the flange of the front tube plate. 3 screws have been made from phosphor bronze





Make up a well polished tapered drift



And lightly expand the ends of the previously annealed tubes





Lots of flux and rings of silver solder around the tubes and silver solder laid around the edge



Heat from 2 torches before the oxy/propane






After siver soldering



All in the pickle again now

Cheers

Rich





Offline Steamer5

  • Global Moderator
  • Full Member
  • *****
  • Posts: 1272
  • The "Naki" New Zealand
Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #251 on: October 13, 2017, 06:39:52 AM »
Hi Rich,
 Looking good, now that Chris has finished his build I can allocate more  :popcorn: to your build!

Cheers Kerrin
Get excited and make something!

Offline Kim

  • Global Moderator
  • Full Member
  • *****
  • Posts: 7860
  • Portland, Oregon, USA
Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #252 on: October 13, 2017, 06:49:04 AM »
More great soldering work there Rich.

Are all the tubes in the boiler the same size?  (other than the center one of course.)  In that last picture, there are a couple of tubes at the top of the picture that look smaller than the others.  Is there a reason for that? Or is it just the way I'm looking at it?

Kim

Offline Firebird

  • Full Member
  • ****
  • Posts: 1328
  • East Midlands UK
Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #253 on: October 13, 2017, 11:33:58 AM »
Hi

Thanks Kerrin  :ThumbsUp:

Kim, the smaller ones are tapped bushes, 3/8" x 40 tpi. One is for the solid stay and one is for the blower tube. The stay and tube go from the smoke box tube plate all the way through to the backhead. The backhead bushes are the ones I have had to make eccentric bushes for.

Cheers

Rich

Offline Firebird

  • Full Member
  • ****
  • Posts: 1328
  • East Midlands UK
Re: CONWAY 0-4-0 3 1/2" GAUGE LOCO
« Reply #254 on: October 14, 2017, 08:42:28 PM »
Hi

Work on the boiler has stopped temporarily while I wait for the copper rivets for the stays to arrive.

To amuse myself I thought I would have a go at the regulator. It looks like a casting but none are available so it has to be fabricated. Firstly though I had to brush up on screw cutting. I have done a little screw cutting some years ago but none since. Having sorted out the correct gears and a few practice pieces made it was onto the regulator. I have already made the 1/2" x 32tpi tapped bush that will be silver soldered into the back head. Firstly a bit of scrap brass is drilled and tapped 1/2" x 32tpi which will be used as a mandrel and test nut. Machine a bit of 3/4" brass down to 1/2" and screw cut the thread. While I was at it I made 2 in case there was any cock ups later on



Screw them into the mandrel and face to size



Which gives us these



They have to be bored and tapped 3/8" x 40tpi. Remember the cock up I mentioned well here it is. I bored it to big  :facepalm2: :facepalm:. I manage to salvage it by tapping 7/16" x 32tpi. the second one I made correctly



A largish bit of brass is machined to 1.2" and bored to 3/4" the same as the flange on the tapped body, then part off








In the mill and machine away some of the waste

Which gives us this. There should be enough for me to get 2 out of it



which gives us this bit



Which hopefully when silver soldered to the body will do the trick




Cheers

Rich



 


« Last Edit: October 14, 2017, 08:47:25 PM by Firebird »

 

SimplePortal 2.3.5 © 2008-2012, SimplePortal