PVC Air Cannon

I built a Pneumatic cannon that is made of PVC pipe. It is relatively easy to understand and build. It shoots far and is safe to use if you build it properly.

Supplies

(all PVC must be at least schedule 40)

2" PVC pipe 10 ft

1" PVC pipe 6 inches,

2x 2" PVC coupler

2" PVC end cap

2x 2"to 1" reducer bushing

2x 1" slip-to-male threaded adapter

sprinkler valve

1/4" NPT tap and 7/16 drill bit

1/4" NPT coupler, male

1/4" NPT coupler, female

1/4" NPT brass drain valve

PVC cement + primer

epoxy

Teflon tape

psi Gauge

schrader valve/tank valve

Air blowgun

you will also need a wrench, a sawzall or hacksaw, tape measure, file/bench grinder, sand paper, and either a air compressor or bike pump.

Step 1: Pipes

In this you will build the barrel and air chamber. you will also cut the 1" pipe. I used a 24 inch barrel and 30 inch air chamber. once you have measured and cut the pipe use sand paper and sand down the edges of where you cut. Cut the 1" wide pipe into two 1.5" pieces sand the edges when you are done. Once you have done that assemble the air chamber without cementing. Cover one end with the end cap and put the coupler on the other. Put the reducer in the coupler the the 1" pipe goes into the reducer which then connects into the threaded adapter. Do this loosely so you can understand how it goes when the time comes to prime and cement. Repeat this possess for the 24" barrel but with no end cap.

Step 2: Cement

Once you have loosely assembled the pipe you can start adding the primer. Prime every joint where pipe connects once you have primed the joints apply PVC cement. Make sure you do this step outside or in a very ventilated area. Once you have cemented the joints quickly push them into place and twist as you do they should go easy if you do it fast enough. Once your barrel and air chamber are dry rap the threaded pieces at least 5 times with Teflon tape make sure it is tight.

Step 3: Sprinkler Valve

Cut off 1.5" off of the solenoid and completely cover it with epoxy it may take 24 hours for it to fully dry. Take the top piece off and drill a 7/16 hole through the middle be careful of the spring. Once you have made your whole use the tap and tap out the hole. Once the hole is threaded wrap both ends of NPT the male coupler with three raps of Teflon tape. Use a wrench and put it into the threaded hole. Now compress put both halves back together and make sure the spring is compressed. Put the female coupler on the male coupler then get another male coupler rap both sides with teflon tape and attach that to the other side of the female coupler. Now take the blowgun and screw the male coupler into it.

Step 4: Valves

With the 7/16 drill bit drill three holes that are 90 degrees apart on the end cap. Tap out the holes this is where you will put the drain valve, tank valve, and psi gauge. Rap each bolt with Teflon tape. Arrange them in a way that is easiest for yourself.

Step 5: Putting It Together

When you attach the barrel and air chamber to the sprinkler valve make sure the arrow on the sprinkler valve is facing towards the barrel away from the air chamber arrange it so the blowgun is facing the ground.

Step 6: Other Things to Know

You will need a bike pump or air compressor to fill up the chamber. Also an important reminder that PVC pipe can be explode under high pressure so if you are going to make this do not fill past 120 PSI and always use schedule 40 PVC. Use at your own risk.