How to make potato launcher / canon

Method 1:

1.
1. Create the air chamber. Cut two lengths of 2"-diameter pipe 30" long and a third 6" long. On the end of one, glue on the 2"x1" SPIGOT x FIPT reducer bushing. To do this, glue the bushing into the coupling, then glue the coupling onto the pipe. Using the elbows, then make a U-shaped pipe, with the 6" section as the bottom of the U. Cut the bike tube off of the valve, leaving the valve and a small flap of rubber around then the valve, about 3/4" wide. Before gluing on the pipe endcap, drill a hole in the center of the cap just big enough for the bike valve. Insert the valve, cut from the tube, and tighten the valve on the cap using the nut. Then glue the cap on the open end of pipe. Where the female threads are, thread the 3" long pipe nipple. Be sure to use the teflon tape on the male threads of the nipple!
2. Make the barrel. Cut a length of 2" diameter pipe 36" long (remember, you can always trim this down later!), and also cut a 4" long piece of 1"-diameter pipe. Glue the remaining reducer bushing into one end of the barrel (to do this, glue the bushing into the coupling, then glue the coupling onto the pipe), then glue the 1" pipe into the bushing. Finally, glue the 1" SOCKET x MIP adapter on the end of the 1" pipe.
3. Put Teflon tape on the open end of the air chamber's pipe nipple. Thread the air chamber into the valve. BE SURE THE AIR WILL MOVE IN THE CORRECT DIRECTION!! Air from the chamber needs to move into the IN hole of the valve, and out of the OUT hole of the valve, as indicated by arrows. Tighten down until snug, and be sure to position the valve on the chamber so there is room for the barrel.
4. Put Teflon tape on the threads on the end of the barrel. Thread this into the OUT hole of the valve until snug.
5. Hook up a 24v DC or AC power source to the solenoid. 3 9v batteries wired together (in series) to make 27v works perfectly. A 12v battery will work effectively, too. Applying voltage will open the valve, cutting it off will close the valve.
6. Load the ammunition (potatoes, fruits, balls, towels, etc.)
7. Fill the air chamber with a normal bike pump or a REGULATED air compressor using the valve on the air chamber.
8. Apply voltage to open the valve, thus FIRING THE GUN. Have fun!



Method 2:

1.
1. Get all your parts ready for assembly.
2. Cut all your pipes to the correct length using a saw.
3. Glue the end cap holder onto the end combustion chamber pipe (Fatter, shorter one) Make sure you don't get glue into the threads.
4. Take the 3" to 1.5" reducer and glue the 3" end to the other side of the combustion chamber.
5. Glue the barrel to the other end of the reducer.
6. Put two 3-inch nails into the 3" section on either side so there about 1 cm apart.
7. Put small alligator clips on the leads to your BBQ sparker.
8. Let it dry for a day, then you're ready to fire.



Loading:

1.
1. Ensure a tight seal around the projectile. This prevents the combustion gasses from escaping around the projectile instead of pushing it forward and will result in inefficient shots.
2. Cut each potato in half and put it on a board or hard ground. Use the barrel as a cookie-cutter to force a perfect circle of potato into the muzzle and force it down with a ramrod.



Firing:

1.
1. Open the end cap.
2. Spray propellant (almost all hairspray will do) inside the chamber and close end cap tightly. Just a quick half-second spray is plenty.
3. Connect the alligator clips to the nails in the chamber.
4. Aim away from all people and click the sparker (it may take a few sparks so don't be discouraged if it doesn't work).

How to build a Potato launcher

How to build a Potato Cannon 2