pic: T-Shirt Launcher, still needs a chasis

[Bruceb]

Well it took me a while but I read this intire thread. What a great discussion. First let me say that I think I will build a sheet aluminum clamp to completely encase the pressure tank. Think of it like a hose clamp that is as wide as the tank is long. Make it from .050 aluminum and roll it to the exact diameter of the pressure tank then bolt the ends together every 2 inches. That should eliminate the potential failure of the pressure tank. The chambers are sealed on both ends by a spring loaded piece of 3 inch pvc. These seals open somewhat every time the gun is fired and I am sure they will release all the pressure very rapidly in the event the t-shirt refuses to go down the barrel. As was said before, if the gun is fired when the chambers are not properly indexed then the seals do not ....seal.. :>) So that is not a problem. Squirrel, this looks like your valve because I am far better at copying an idea than I am at coming up with my own. It is your valve as best as I could tell from the pictures. At least I think it was you. It is only a 3/4 in gate valve. I believe the small size of the valve actually limits the pressure buld up in the barrel quit a bit. As far as the big reducer at the back of the barrel not being pressure rated goes, that is not a problem either as it is not carrying ANY pressure. The one inch pvc that is connected to the union goes all the way through the reducer to the back of the chamber and is sealed at that end as well so no pressure can get into the reducer at all.

Why not build it all from something stronger(read that more expensive)? Budget is all I can say. If anybody wants to donate some 4 inch steel pipe and the necessary fittings I would be happy to use them. No, I'm not ignoring the safety concernes due to budget constraints. We built the thing with the aid of 2 GE engineers who don't see how the PVC can be a problem. That was before this thread got started and all the concerne got started so now I am trying to minimize the risk and concern using materials we have available.
Thanks for all you input. Keep it coming.

Bruce