high pressure vessels

[acoop101]

I was looking at these high presure spheres
http://www.aeroconsystems.com/plumbing/ ... pheres.htm
and was wondering if anyone knows where to get something like this that aren't stainless steel and could be used to make a spud gun? I just can't bring my self to pay that much

[Fnord]

I think I've mentioned this before. Somewhere.

Salad bowls+solder/small bolts.

It won't be good for more than a propane combustion, or at least I wouldn't trust it with more.
You could always try to aquire a de-commisioned nuke and use the blast containment sphere, which should be rated for several thousand BAR.
This of course is well within the capability/budget of an average teenager.

[acoop101]

I am a pressure vessle builder by trade but I haven't been able to find the steel half spheres, I only really need it rated to 150~ psi so it's not that much of a problem but no one makes them. I usually make vessels rated for up to 8000 psi.

[Fnord]

Well, if you're already in the industry, have you ever seen the lathes that are used to bend sheet metal into bowl or cylinder-shaped containers?

Basically a disk of sheet metal is spun and pressed against the outside of a die using either hand tools or some type of automaton.
I don't know if you would have access to anything like this, but maybe you could adapt a regular lathe in some way to suit this purpose. A bowling ball would be a good die, in this case.

[acoop101]

I wish I had the sill and I wish my company had the equipment to do it. But I was going to make it out of 1/4 inch steel plate. I am always of the opinion that it is better to over build than to not build enough. I may just use a 9 gram co2 tank.

[Fnord]

Ok, I got another idea for you. I just realized I already had something sitting around that is kinda like what you are looking for.

This is a bouy from who knows where. Notice how it appears to be made of welded metal rings layered together. If you have access to a cutting torch/welder, this should be reasonably easy to construct. It will take some time though, especially if you want it too look nice.

Does it have to be perfectly round?