That's what they call a 'jumbo' valve. Imagine their miniature line of QEVs, worlds smallest pneumatic.

Looks way to small to me. Unless you are making a mini, QEV mini, nice.

I would say Araldite, I've never seen JB Weld though don't think they have it here in Australia. I find that 5 minute araldite gets the job done for most things but if you need super strength go for the 24 hour stuff. I usually let the 5 mitute stuff cure for an hour anyway.

Ive made a gun with it but I left it at a mates house, I'm going to go get it tomorrow so I'll put some vids up then. I used 3DS Max for the render.

I finally got round to making a semi-auto marble cannon on the weekend. At first I tried to use a paintball style blowforward design like this but it didn't work, tolerences required were to close and I don't have a lathe or access to pvc rod. So then I got thinking and came up with this design and ...

Propane only runs at like 120 - 150 psi I've got a propane tank for my pneumatics and it works perfectly. I'm gonna post a thread on my setup in the not to distant future. There is a vid of me filling one of my guns with it here.

For a prototype why don't you try and use the trigger mechanism from a cap gun. Would save time designing a trigger mech yourself (they can be really annoying to get right).

If you need a 20mm sprinkler valve I've got one left over.

Mine is roughly based on the AWP(technically the AWM), but I would have loved to do either a TPG-1( My favorite rifle) or a Parker Hale M85. But I think that making wooden furniture based on a polymer rifle doesn't look as good as making furniture designed for wood.

What colour do you guys reckon I should paint it. I'm thinking either Woodland Camo, Urban black or a Walnut stain. The barrel is gonna be either Matte black (cant go wrong) or I might try Woodland on the barrel as well as the stock.

At pressures as extreme as 830psi I dont know if ABS will still rupture, it might fragment. My advice would be to find the thickest metal pipe you can and then bury it in the densest material you can find, ie, soil, sand, cement.

Because there is a 20% (I think) vapour space in the tank there shouldn't be any liquid in the chamber, because most of the expanding is done in the tank only vapour should come out.

Yeah, those are the ones. They're insane.
I want one.

lol, Im still thinking of propane, I just wrote a PM about it. Man thats funny.

if I have a compressed gas reservoir with a volume not significantly greater than 160 ml (10 ci), or any reservoir volume less than this figure, and it were to be exposed directly to an unregulated 16g (0.56 oz) CO2 cartridge, it would theoretically fill the reservoir to something approaching its o...