Introduction: Self Contained Air Powered Potato Cannon
Ever since I was a young kid I was fascinated with potato cannons. Early versions were powered by Right Guard aerosol deodorant (the cheapest fuel we could find at the local drug store). The smell of that deodorant still brings back waves of nostalgia. Although effective, I always feared that too much pressure would build up during the violent ignition and our potato gun would shatter in our hands. The other option was to use compressed air but being broke high schoolers meant we didn't have money for an air compressor nor was it feasible to bring one out to the woods with us. After stripping down an old portable jump starter/compressor for parts, I wondered if it was possible to use the mini compressor to build a self contained air powered potato cannon. Surprisingly it worked out really well!
Step 1: Harvesting the Air Compressor
I had an old jump starter battery/compressor laying around. The battery would no longer hold a charge so I decided to strip it down for parts. As I was disassembling it I thought, this would be pretty awesome if I strapped it to a potato cannon. For reference, this is the model I had on hand. https://amzn.to/3hpZ7ii
After isolating the compressor and pressure gauge, I cut some thin plywood to cover up the exposed side. I used some of the case screws to fix the wood to the compressor assembly. I cut the extra screw lengths off with a Dremel. I also drilled some holes for zip tie mounts.
Step 2: Air Valve End Cap
To connect the air compressor to the air cannon, I bought some tubeless valve stems to install in the 2" PVC end cap. I didn't have to use any glue as the rubber gasket provided a good enough seal. https://amzn.to/3HtLOIl
Step 3: Cannon Construction
The next step was creating the cannon out of PVC parts. All joints were glued except the threaded connections to the sprinkler valve. https://amzn.to/3IuxNeS
I 3D printed a switch housing, a battery holder, and a ramrod holder as well. One switch turns on the compressor and the other opens the sprinkler valve, firing the cannon.
Step 4: Battery
To power the compressor and sprinkler valve I bought a 5200mAh LiPo battery. https://amzn.to/340tA3y
I cut off the connectors and used some XTC connectors that are common for LiPo chargers. https://amzn.to/3smYJHH
Step 5: Fire Test
Participated in the
PVC Speed Challenge