Just enough

[paul]

Made the basics for the new boiler - it should have just enough capacity to 'boil' scotch egg. ;D



Next up holes, bronze bushes, some sort of regulator and a housing. Oh yeah, I guess it'll need soldering too

[paul]

Made most of the housing now - just need to solder on the end panels and make a snazzy brass bit for the chimney.

The fittings weren't supposed to be so close to the stack but a concentration malfunction meant that the boiler tube had to be shortened and a new hole added but because it's a home-brew affair it doesn't really matter (life is so much easier when not working to a prototype ;D ).

The boiler will be held by nuts on a couple of bits of studding on either end, not the extra long bit of steel rammed in there for the photo

[paul]

Cut out the 'firebox' hole and soldered it all together. Originally I was going to spray it matt black like the fancy Stuart boilers but not sure if I'll bother as not too much solder is visible.

[circlip]

Hope you've got a bit more than just solder holding the casing together Paul?

[paul]

Yep, the boiler has (well, will have) 6mm studs on either end passing through the end parts of the frame and secured with nuts so it should manage to hold it together as the ends squeeze together both the sides and the top. I'm making this up as I go along so it might need more - we'll see!

[circlip]

Was thinking Brass/Heat/Solder = pile of bits while you're trying to run it. Even with insulation I would have thought you would have needed to silver solder?

[paul]

The 'toy' kit-built engine I have has a brass boiler with soft soldered end plates (yikes!) and seems to cope with the temperature (using fuel tablets) so I'm basing my guess on that. If the worst comes to the worst I can add some rivets to the top/sides.

[circlip]

Yes Paul but the boiler with the soft soldered ends has got water inside it, it does make a difference sunbeam.All the Mamods had soft soldered cylinder to cradle joints on the early wobbler's, but they were only looking at steam heat, but I think (could be wrong) that the boiler end cups were silver soldered on.

[paul]

Groan. Never mind, let's wait and see what happens - worst case scenario the solder runs but it won't fall apart even if all the solder disappears.

[circlip]

Boiler joints should be OK,(don't let it run dry), will keep my fingers crossed for you over casing.

[paul]

No mate, the boiler is silver soldered it's only parts of the housing that are soft soldered - rivets at the ready!

[paul]

Completed a pressure test and first steam/safety valve test today and all went swimmingly.

Discovered I'd mucked up the dimensions for the boiler housing (er, well no dimensions really, I'm making it up as I go!) so re-working that - the new version will be a more conventional design, fortunately I can re-use all the parts I've made, just need to chop 'em around a bit. Hope to have it powering some of my mini engines before the week is out.

[circlip]

It's called empirical design Paul, all the best designs work on this principle.

[paul]

Bugger, bugger, bugger. I've empiricaled it up!

Ah well, no biggie. Just drawn up some *plans* (with proper numbers etc) to make a new one.

[circlip]

You don't need Bling for your casings Paul, the people in TLOTF only use it cos their wives won't let them put their toys on display in the living room unless it glisters like gold. Steel or aluminum (yes I know) is cheaper. Ian

[paul]

Well the new version is about 10% made and will have aluminium angle holding the bits together Filing thin sheets of brass square is a real pain in the bum aint it? I'd be happy propping the boiler up on a couple of house bricks but as you say that's not allowed ;D