New Steel Boiler for under £200

Ive got the steel on order - 5" OD x 22" long, with certs, the designs are almost complete and ive got a copy of the blue book. Im trying to make it for under 200 squids!! Im going to do a build update if anyone is interested. Ive done all the calculations and it should steam just fine. I would be interested to know what the smallest dia tubes have worked for you - these are 13" long. My calculations make certain assumptions so ive got a little room for manouver on tube size - more and min dia is what i want. Coming out at 7/16 od but would like to know if yours are smaller. If youve got first hand experience of something like this then I would welcome input, I dont mean to offend anyone but if your going to tell me how it cant be done without having the data to back it up then......(im fedup with hearing people tell me what wont work without them having any proof to back their statement up).

Well My fowler has a 4 3/4" copper boiler so ID will be about teh same as your steel one, that has 21No tubes 7/16" dia, not run mine yet but others I have driven steam well.

Yes would be interested in tehbuild, we like plenty of photos to go with it. The next traction engine I'm going to do has a steel boiler and would be interested in doing all the weld prep etc myself and just getting it welded up.

J

Boiler now wellunderway - photos to follow. Drawings revised as per inspecter requirements, all materials purchased, TIG set serviced. All the time consuming parts are now cut, drilled, honed. Even welded the dome bush on! Im still undecided as to whether to expand the tubes or silver solder them. Just need a 1/2 x 32tpi tap for the wet header.

Looking forward to the pics, never had the courage to build a boiler always bought them in

Bob

Yes I'm looking forward to seing the boiler come together, would also be nice to see some of the platework before assembly as the weld prep is also interesting to see.

I take it that you are having your welds checked by the inspector as I seem to recall you were not coded but a competent welder, what sort of cost would these tests add to the build if you don't mind me asking, hopefully still a lot lest than having one made,

J

Im having all the welds professionally tested by a NDT company, quote for test and written report is £60. The whole job will take less than 5 minutes. I will take pix of the weld preps also. Preps are something which requires a lot more thought than you would imagine! All welds are to be full strength, full penetration. I had to submit a full weld profile diagram with the overall designs. Welding it up with the mig would have been very easy but I think tig looks much better.

pics uploaded to album steel boiler I cant get them to insert into thread!

Fizzy

Seriously impressed by your work.

Bob

dome hole cut - had to chain drill it astube steel too hard for cutter!

cutter teeth no more!

dome inner boss tigged in - 4mm undercut as prep. Bit rusty with the olde tig set but nice even heat as seen by blue colouration ring

tapping holes for manifold, water gauge and pressure valve - had to turn tap with adjustables, told you it was hard as hell! Slightly overdrill size would have been a much better idea! Small spirit level to check nothing moves.

boiler tube cut away. You can just about see the finished smoke box on the far right (and my scrap items box on the left)

all drawn to scale on Visio so I can take measurements from drawing, and separate cutting profile for each part drawn - cut out - spray glued to steel. Centres popped and cut around profile.

almost finished these two - individually marked out and drilled and very close! 12 holes 7/16 and 4 @ 1/2. The two outermost were supposed to be 3/4 for superheaters but thats a bit ambitious me thinks! The right hand stay hole has now been redrilled and tapped to take a brass ferrule which has an internal thread of 1/4 x 40 tpi for the blast steam transfer.

this is the end of Sunday - most plates roughly cut to size with the plasma disc. I even labelled them up! Will keep you posted if interested - any questuins, please ask.

end plate welded on

smoke box welds

smoke box in position