F.A.Q. 

Is combustion or pneumatic type better for me?

Definitely a pneumatic cannon. I prefer the pneumatic type as it is safer, cleaner and more reliable. It is easy to build and operate and costs less in the long run than a combustion cannon.

HELP! I didn't receive a link to download my file!

If you did not receive an email directing you where to download your file just send up a different email address from a different host so we can send you your file. The reason why we are asking for a different email address is because our host or your host might be blocking one of our IP addresses therefore we will not be able to email you your file.

How far will this Air Cannon launch the balls?

From 25 feet to 200 feet.

Are these things legal?

That depends on where you live. The Fed's say they are OK as the letter below outlines. I have heard of several instances where they were 'not legal' but that has usually been due to the operator using a launcher in an unacceptable manner (shooting a hole in the neighbors house). Many cities and munincipalities have local ordances pertaining to the use of spudguns inside city limits. Ask someone that would know on the local level.

Are they easy to build if I don't know anything about building things?

The plans take you step by step through building the cannon. They come complete with pictures, part numbers and a simple step by step tutorial that shows you the length of each piece and where to glue them together. If you can glue two pieces of pipe together, then you can build this cannon.

How to calculate the velocity of your ball?

Set the canon at a measured height off the ground. Fire the canon level with the ground and measure the distance it travels till it hits the ground ( you will need the ground to be level). Knowing the distance the ball travels, that gravity is 9.81, and the height of the gun. All you do from here is :
t(time) = (h(height)/4.905)^.5
V(velocity) = D(distance the ball travels) * t(time)
*Note gravity is in meters per second squared
time is in seconds
height and distance is in meters
velocity is in meters per second

What glue do you recommend?

I use "Oatey Purple Primer Primer" and "Christy's Red Hot Blue Glue" from Home Depot or Lowes. I always primer the parts I am gluing together first and then use the Christy's Red Hot glue on both joints before connecting. Be sure to use an ample amount and twist the parts together to make sure they are air tight.

The pipe I bought has SCH 40 printed on it...But it also says DWV...Is it ok to use?

When selecting pipe for use in building a air cannon or other type of novelty launching device, make sure the pipe has a pressure rating printed on the pipe. The typical printing on a length of pressure rated pipe will look something like this: (2" PVC pipe)

"MANUFACTURES NAME" PVC 1120 SCH 40 ASTM D-1785 NSF-PW 280 PSI @ 73F

The thing you want to look for is the NSF-PW 280 PSI (or whatever the psi rating is on that size of pipe) It doesn't matter if it is SCH 40, 80, or 120....Look for the pressure rating.

If the pipe has a pressure rating on it, it is ok to use. The reason that it also says DWV is because all ratings for the pipe must be labeled. If a piece of pipe is rated for 280 psi...It is obviously approved for use as drain pipe. There are all kinds of labels you might find. One is "cellular core". If it has a cellular core label...dont even think about using that for a air cannon. It will eventually fail on you.

What should I use for fuel?

Use air. It's free. non toxic and the tennis ball cannon will launch every time.

How long should I wait for the glue to cure?

AT LEAST 24 Hours! Proper solvent welding is a must, and the joints should be allowed to fully cure before loaded with the the stresses of igniting something quickly.