Yeah, that's where I'm concerned. Originally, I thought of playing
with a household pressure cooker, but the problem is that I need that
valve on the bottom for letting things out properly. I suppose I could
modify a pressure cooker, but it would need to be a big one.

I suppose I'm probably over-engineering, too. It probably only really
needs to hold 30-50psi, but I'm being conservative, I guess. It would
really need a failsafe, too, now that I think about it...