SpudFiles

I am working to build my first potato cannon. It will be used to conduct impact testing, and will be stationary so weight isn't an issue. It will be built from copper or aluminum, any suggestions on which would be greatly appreciated. I need at minimum a 2" barrel and it will be pneumatically powered. I have a basic design with a chamber being 5' and barrel being 4'. I don't need anything fancy, but am looking to use a store bought quick exhaust valve and a ball valve. However, I am still working to understand how these components could work together. Any advice or direction is greatly appreciated.

Welcome to the forum!

If it's for a static large bore rig, a burst disk might be a better option as store bough valves will get pricey.

Something like this:



Your chamber and and barrel are separated by a union in which you have a disk of frangible material sealing off the chamber. In order to fire, you pressurize the chamber until the pressure become too great for the disk to contain it causing it to rupture.

This will give you maximum power for minimum cost, it takes slightly longer to set up than a re-settable valve but for your purposes this should not be an issue.