When building this cannon, change the ignition system into a pneumatic one.  Just use my Pneumatic Add-On to convert this to a more powerful cannon.

PARTS


•3'' by 3'' by 3'' are the front openings and a 3'' for the rear opening.  This is the chamber and it looks kind of like a duck foot.





•three 3'' to 1.5'' reducers  (these are flat reducers)





•1.5'' diameter by 19.5'' long  (the two outer barrels)





•1.5'' diameter by 21.5'' long  (the center barrel)





•two 45 degree pipes with 3'' openings  (this is so you can get all three barrels going in the same direction)





•3'' Cleanout with screw cap





•Pneumatic Add-On



Assembly

Just like any other cannon you assemble this one the same way.  I put bolts through the barrels to hold them extra tight and also so the potato doesn't fall back into the chamber.

For the power use my Pneumatic Add-On.  Then use the Filling the Air Chamber Page to fill it and use the Valve System Page to learn to hook that up.  I'll help you out if you have any troubles.