Just what is an air cannon or potato launcher you may be asking. Well there are many different
types of air cannons or potato launchers or air potato guns in use out there today. The present air cannons, potato
launchers or air potato guns evolved from the spud gun. A spud gun is a piece of pipe modified to shoot a potato
or parts of one long distances. Over the years, the spud gun has been made safer and stronger, as well as larger.
Air cannons or potato launchers or air potato guns are not traditional spud guns. Air cannons,spud gun or potato
cannons use, you guessed it, air, as a propellant. Older spud guns used a flammable propellant such as hair spray,
usually ignited by a lighter or match, to launch things. As you can guess, this wasn't a very safe practice and
something safer was soon developed. That development was the spud gun or potato cannon air cannon. spud gun or
potato cannon Air cannons are normally made out of two pieces of pipe separated by a valve that when opened, lets
air through to the barrel and fires whatever is in the barrel. The first piece of pipe is the barrel, and the second
one is the air chamber, which is filled through a tire stem valve. The typical barrel and air chamber length is
around three feet, though I have seen some to both extremes of that measurement. The air cannon that I built has
a barrel length of three feet and the sound made when fired is roughly equal to the sound of a door slamming. Of
course, the sound of a door slamming depends on your door, but in general, that is about how loud it is. The valve
that separates the the barrel and air chamber is typically a lawn sprinkler valve or is some cases a ball valve.
The preference of most people is a lawn sprinkler valve because it can be electrically operated instead of having
to manually open the valve.
I will not tell you on this site how to build an air cannon. However, I will give you some pointers to watch out
for when building one, as well as some fun things to do with it. This site tells you some of the things I learned
while building my personal air cannon. The responsibility to use the information found here appropriately is solely
yours. Serious injury could result from the building, misuse, and disassembling of an air cannon or similar devices.
An air cannon should never be aimed at or fired upon a person not wearing the appropriate protective equipment.
Even though you may be using safety equipment, air cannons are still very dangerous and should be treated with
extreme care.
My air cannon is built of 2" PVC and has a 3' removable barrel. The valve is a manual PVC ball valve. My air
chamber is about 3' long as well as has a carrying handle built into it. I have a 200psi pressure gauge attached
to the air chamber as well, so I can tell the exact pressure inside the cannon, not what the air pump says it's
putting in.
The cannon that I made was originally built for use as a multiple round paintball launcher (MRPL), or as I call
it a Paintball Assault Cannon (PAC). While testing the final cannon, I determined a few safety rules that I would
always follow while I was using it.
1. I will be the only one who can fire the cannon at people. This sounds strange but let me explain. I like to
let other people have fun, so I let them play with the cannon. Many things can be fired from it other than paintballs.
However, when it is being used for paintball, I am the only one who will be using it. This is because I must be
operating the cannon at under 90psi and be that distance away. If I am operating at 80psi, I can be 80 feet away,
and so on. This is to prevent the severe pain associated with the possibility of being hit with 22 paintballs at
once. Also, if I am the only one using it, that it will be used at the correct times and used appropriately.
2. The cannon I built will never again be operated at a pressure of more than 100psi. I say never again because
I fired the cannon at 115psi three times without any problems. I now know that the my cannon can be safely operated
at 100psi or lower.
3. The cannon should be pressure tested at least once a month, depending on how much it is fired. Testing can be
done by filling up the cannon and taking a pressure reading (use a tire gauge if you didn't install a dial indicator)
right after filling it. Leave the pressurized cannon sit somewhere (not in the house) for 24 hours. After 24 hours,
take another pressure reading. If the pressure has dropped, submerge the cannon is a bathtub to locate where the
pressure loss is coming from. If it is leaking from around the threads near the valve the problem may be able to
be fixed. If it is leaking from a glued fitting or from anywhere along the pipe, do not fire the cannon again.
It must be taken apart and rebuilt, since you cannot re-glue a fitting. If air was leaking from the length of the
air chamber, it is possible that the crack would become larger and could burst in the future, causing the loss
of an arm or worse. |
