Building a Boiler for a 3 1/2" Gauge Locomotive

[Stilldrillin]

Stew,

I store all that collet stuff in small polythene bags, with a fuff of WD40, in their own dedicated plastic box.

I tend to think people who store shineys that way, have a much drier workshop atmosphere than mine...... 

David D

P.S.

Nice work! 

[madjackghengis]

Hi Stew, nice work on the "fire hole", the oval looks just right for the job.  I like the way you set up the boring head for doing that radius to match the boiler, I've done the "cut and try method" a few times, and that way looks to save a bit of time.  It looks good sitting on top of the boiler tube with it's threads all exposed and all. I just thought I'd mention the issue of rust and MDF, when they finish with making the MDF, there's lots of formaldahyde left in the boards, and it strips all oils and such off as it evaporates out of the boards.  It will come out, pretty much without regard to what you cover it with, but once it is gone, usually a year or so, the problem is over.  You might think about slipping the shanks in a baggie or something before dropping them in the board.  Trying not to make to many posts about this simple little thing.    mad jack

[sbwhart]

Thanks for the warning with the chip board, I'll have to take some precautions.

Showed the boiler to the inspector today big thumbs up .

Stew

[Divided he ad]

Showed the boiler to me as well


I have to say I had a good lesson from Stew and Bogs on how it all works too.....Never really been party to the full workings of "the boiler"... Know a lot more now though 

Looked very good from where I was sitting Stew 


I liked the gauge mounting too 





Ralph.

[sbwhart]

Thanks Ralph it was good meeting up and chewing the fat.

Got a little bit more done today, cut the fire hole in the firebox back plate for the, just making it a nice fit just a little bit of movement from the fire hole ring.



Then soldered the ring in place, and while I was at it I solder some of the bushes in the backhead.





Thats a little more done.

Stew

[shoey51]

  lovin your work Stew

[madjackghengis]

Doing great work, Stew, I guess you're here to set the standard for us regular folks.  I've got to say, the soldering job on that fire hole and the bushes is a work of art, great to hear the boiler inspector likes your work too.  You should be done with this boiler pretty ricky tik, and ready to show us some steam and pressure   this thread is the motivation I needed to get past my hesitation to build one for my next steam engine, the one I've had in a box unmade for a few years.  Did I mention gorgeous work already?  nothing but beautiful mad jack

[NickG]

Stew, forgot to ask, is all the solder you're using easy flow 2? Are you following Curly's build instructions? Just wondered because I know on mine some of it is sif bronzed and some different grades of silver solder so that you don't melt what you've already done.

Nick

[sbwhart]

Nick

For the firebox extensions I used easyflo No 1 which is a slightly higher melting point I reasoned that this joint will be subjected to quite a number of reheating, for the same reason on fire box hole and the backhead bushes I've used some high melting point silver solder that John gave me, but before I used it I had a trial run on the scrap firebox tube plate just to see if I could get it up to temperature.

Cheers

Stew

[NickG]

Stew,

Thanks for the info, though you must be using different types. Keep up the good work.

Nick

[sbwhart]

Things bin a bit slow as we had a short holiday in London.

The guys at the club and the boiler inspector advised me to use rivet stays as they are far easyer to put in and just as effective, as the girder stays specified in the drawing. I couldn't get any rivets long enough so decided to make some out of 3/16 copper rod, I made a little upsetting jig this is simply a 3/16 hole in a chunk of steel, split through so that the rivet can be removed. To make the rivets I cut some 40mm length of copper bar, annealed them then put one in the jig with a short length protruding grip it tight in the vice and give it a good wallop with a hammer to upset the head. You can get the idea from the pic.



Another bit of advice was not to try drilling rivet hole through both plates at the same time as the drill just wonders and the stays end up crooked, best to carfully mark the two parts out and drill them separately, this is the boiler tube marked out.



And the set up to hold the boiler on the mill table for drilling.



Drilling the stay holes, and safety valve hole



Drilling the hole for the steam dome.



for some reason the steam dome hole was going off line so finished the job off with a file.



Steam dome bush fitted.



Steam dome bush soldered to the boiler.



Drilling the stay holes in the firebox.



And a trial fitting of the parts the stays are not fully assembled in place.



John was coming over this afternoon to help solder the stays but it was raining so we,ve put it off until Thursday.

Cheers

Stew

[Stilldrillin]

Really nice work, nicely shown, Stew!      

David D

[Dean W]

Looking good, Stew.  Thanks for showing how you did the stays.
Maybe you've already said, but, what will fire the boiler?

Thanks for the show!

Dean

[sbwhart]

Thanks Dave/Dean

Dean the boiler will be fired with Coal, you can still get Welsh Steam Coal in the UK theirs a small mine still in operation, producing good anthracite coal, its a very hot burning coal that fired the industrial revolution in the UK. I've watched the chaps a number of times at the club fire up their engines it always amazes me just how quickly they come up to steam in about 5 minutes.

Cheers

Stew

[shoey51]

  absolutely marvellous Stew
Im watching this thread closely 

[NickG]

Excellent Stew,

This is a brilliant guide for anybody making a boiler and interesting for anyone that isn't!

In my experience it takes about 15-20 mins for a small boiler like this to steam up but maybe that's with normal anthracite beans.

You're right some people do swear by that welsh steam coal.

Funny you mentioned it, one of the Thomas the Tank Engine stories I read to my son refers to it. They need to use it for an engine that has a relatively small firebox and can't cope on normal coal! There's a useless fact for you sorry, bit 

Nick

[sbwhart]

Thanks Guys

My Grandfather was a engine driver in the steam days and I can remember him saying how the best coal was welsh steam coal, and how the firemen use to cuss if they had anything else, as it made for hard work keeping the pressure up in the loco.

There's  a huge loco at the York railway museum that was made by the North British Loco works in Glasgow for China, it was designed to run on poor quality coal, it had a massive coal bunker and foot plate so that they could have two or three firemen shuvelling the stuff on.

Stew

[Dean W]

...the boiler will be fired with Coal..
Stew

Neat, Stew.  Steam and smoke!  Love that stuff.

[madjackghengis]

Hi guys, hi Stew, based on my long research and experience, the best anthracite coal can be close to 95 or 96% carbon, with almost no hydro-carbons to "gas off", and is, as it comes out of the mine, equivalent to the best coke, but denser.  Bitumus coal can easily be less than forty percent carbon, with the remainder being hydrocarbons which must be "cooked off" if the full caloric value of the carbon is to be available.  "Good" bitumus coal would be 75% or better carbon, and similar to good hardwood with regard to "coking off" as a parallel to doing the same with the hardwood to produce top quality charcoal.  The poorer quality bitumus coal is equivalent to pine or other soft wood, it can be cooked off to produce charcoal, but it produces far more gasses, and far less density, and the coal is very similar in the coke it produces, porous and needing compressing to compete with good coke or top quality coal.  I expect the "Welsh coal" is similar to some of the best we get out of the mountains of West Virginia, it comes from deep, from veins that once were very deep in the mantle.  Hard as rock breaks up like crystal, burns with almost no smoke, very hot, very heavy, almost solid carbon.  For what it's worth, I just wish I had a ton or so sitting behind my shop right about now.    mad jack

[sbwhart]

Cheers Dean/Jack

Jack sound like you've got some good coal in your parts.

Any way the rain kept off today so manages to get the crown stays done.

The parts were given a good clean and the rivets assembled as the rivet passed through the water space I threaded a ring of easy flow solder onto it, the parts were then fluxed and another ring of solder added to the outside of the boiler tube that way the solder between the plate fed the joint with the fire box and the outside solder fed the boiler tube: so that we did the outside and the inside at the same heating.

The boiler was placed on the hearth firebox down, and with a  large torch in the firebox and one smaller torch on the end of the rivet, on a roving mission, the solder soon melted all looked good, so after 1/2 hr in the pickle this is what we got.

Inside



Outside



In between



All the joints had a nice fillet of solder 

Before I do some more I need to get a few more rods of solder.

The next job will be the throat plate stays and the side stays:- 54 in total.

Cheers

Stew

[sbwhart]

Picked up some more silver solder yesteday I recon I will have put about £30 worth into the boiler by the time its complete. Got on with drilling the rest of the stays after carfully marking out started by drilling the holes in the throat plate, its a a real awkward position up underneath the boiler tube, so that I can reach made up a extended centre drill with a 1/8" drill at the other end:- this is the beast.



Drill a hole in the end and stuck them in place with Loctite.

They ran out quite a bit so had to get them running as best I could with a perswader  also centre popping the hole helped because of the length it was quite flexable so it found position for itselfe.

This is the set up first all the holes were centre drilled.



And drilled 1/8 right through throat plate and fire box.



And her it is with the stays assembled.



Called it a day at that and went in to watch the footie.

Stew

[Stilldrillin]

That`s a bit clever Stew! Well done...... 

While I was employed, I often had to use that method, to drill air holes around long spigot diameters....... Had some 8" L x 5/16" Dia. centre drills made up.

I`m sure I was followed home, one dark night. 

Wonder where it is now..... 

David D

[shoey51]

nice work stew

[sbwhart]

Got some more prep work done today for the next soldering campaign.

Drilled the holes for the side stays, 28 each side right through outer wrapper and fire box wrapper.
This is the set up the well annealed soft copper needed some support from Jacks, centre drill first then 1/8" drill, every fourth hole I pooped a rivet into to keep everything lined up



Gave the stays a trial fit, it looks like a hedgehog.



When it comes to soldering I'm going to thread a ring of solder over each stay as it passes through the water cavity, and one ring around the head of the rivet in the fire box that way each stay will get two rings of solder one to fill the fire box wrapper and the other to fill outer wrapper.

Made the rings by winding the solder around a length of 1/8 bar then snipping them off to make the ring.



And her they all are all 130 they used up 4 lengths of solder at 2 squid a length.



Cheers

Stew

[Dean W]

Looks like you have the makins of chain mail, Stew.  That's a lot of snipping and cutting.
Those rivets are just sticking out everywhere.  Good job.  BTW, how long is a stick of your silver?

every fourth hole I pooped a rivet...

Ooh boy.  You must have sore tushie by now!   

Thanks for the new update!  Great thread!

Dean