The air cannon
is a relatively simple device to make whose capabilities are only limited by the imagination
of the creator.
The supplies needed to make this fun and (generally) harmless item are few and easy to obtain. The supplies I am listing in this writeup are those required for a medium-sized cannon.
- One five gallon plastic bucket. (The orange variety from Home Depot works quite well as a standard.
- One inner tube for a large tractor tire. These can be found at farm supply outlets or online.
- Standard pair of scissors large enough to cut the inner tube.
- A very very hot knife (lighter will suffice to heat up knife)
- A jigsaw or other small cutting device (optional)
- A high impact driving device (duh...a hammer)
First, cut a generous section of inner tube away from the rest. A square piece as large as can be allowed will work nicely. Next, stretch this piece as tightly as possible over the open end of the bucket. his might require the help of a friend as the rubber can be quite tough. While your assistant holds the rubber in place, use liberal amounts of duct tape to secure the seal all the way around the rim of the bucket.
After this seal has been created, heat up your knife as hot as you can get it (unless you own a forge, then just get it nice and toasty without melting the damn thing.) Using this hot punch, make a slice into the other side of the bucket (not the rubber side) about two to three inches out from the center. Using either your jigsaw or re-heating your knife, cut out a concentric circle keeping the radius as constant as possible. Your cannon is complete.
To use the cannon, either hold it hole-end behind you under one arm or have your friend hold it for you. Aim at whatever you want and give the rubber a good whack. A puff of air will shoot out and can actually go for a nice distance before dissipating. The most obvious use for such a non-lethal weapon is to annoy people. A puff of air can send a stranger's hair right up over their face.
Another cool idea I found is to fill the cannon with smoke of any kind (except dry ice fog, it doesn't last too well...) and give it a semi-gentle whack. It blasts out a perfect ring every time. Great party trick. teach your ferret or dog or whatever to jump through a ring shot at it.
The great thing about this puppy is, if you can get the supplies, you can build it as big as you want. My science teacher got carried away and used a 50 gallon drum with melted-together inner tubes as the rubber end. He hits that thing with a sledgehammer. It hurts small children.