My first foray into the world of pneumatic potato cannons. I’ve got lots of experience with combustion cannons, and in fact I think the best combustion design is a propane-fueled, spark-plug ignited beast, but I have almost no experience with compressed air designs. My only prior design was a weak, sickly thing built in 11th grade physics class for launching whiteboard markers across the room.
Features: Interchangeable barrels, safety/arming switch, Weather-resistant battery compartment, pressure gauge, safety screws to prevent blowouts. Most non-PVC parts came from Ax-Man, the best store ever! http://www.ax-man.com/
Close-up of the controls and fill valve.
A half-arsed electrical diagram I drew to help remember what went where in the battery tube.
Development has not been completely bug free. So far I have installed the solenoid backwards once, overpressured the chamber and destroyed a PVC weld once, and screwed up the wiring several times. However, everything seems to be working now! Next up, some distance tests vs the latest combustion cannon.