Mateo Peña Doll

Built from a barbecue lighter and PVC piping, this potato cannon hurles potatoes, tangerines, and apples at 98 miles per hour and up to 200 yards. The design of it was fairly simple, composed of a barrel and a combustion chamber with a removable cap. A longer barrel improves accuracy, but increases the energy lost due to the longer distance for friction to act over. Initially, the barrel was six feet long, but I shortened it to five feet to increase the speed of the projectile, loosing a bit of accuracy. I installed a makeshift silencer made out of a plastic container. It worked well, helping not to disturb the neighbors. In order to fire the cannon, you press the barbecue igniter, which is inserted into a pistol-like grip I carved using a jig saw and file. The barbecue lighter creates a potential across the two screws inserted in the ignition chamber. The spark created between the screws ignites butane, heating the chamber. This causes the gas to rapidly expand, sending the projec