Okay, have your giggler ready.
Today, I decided it would be a fun idea to mess around with my potato gun. I grabbed a cardboard tube, worked my magic, and eventually I had a stubby little circular tube with gravel in the middle and sealed at both ends with bits of tennis balls and a good bit of scotch tape.
I wanted to break through some cardboard with this.
I started out with some thin cardboard, and set it in my rig, which was a large PVC tube surrounded by a wooden rectangular prism with the ends cut off, which I then placed at the end of a cinder block with the hole side facing the cardboard box, and then placed that cinder block was placed against another cinder block with the flat side against the hole, making for a nice test chamber. I put the thin cardboard between the wood/PVC and the cinder block, effectively making it impossible for it to move.
I fired my potato cannon into the PVC, the round broke through perfectly and and landed in the test chamber-everything was just fine.
I reset and put cardboard like you would find on a box where I wanted it to break through. I fired again, and because of a few improvements which made it even more impossible to move, but I could not see the cardboard after I fired even though it stuck up above the chamber several inches.
I was bewildered. I figured the bottom had broken off, and the top had flown somewhere else. I looked around for 30 seconds, and couldn't find it. I eventually began to remove the back cinder block, and to my surprise?
Smoke.
The cardboard had caught on fire, I quickly removed it and moved it over to pavement, where I stomped it out.
I stood there for a minute or so, amazed. I eventually went back to the test chamber, where to my surprise?
More smoke.
The tennis ball and cardboard round had completely ripped apart, and the tennis ball bit had caught fire, when the cardboard was smoldering.
I went in to my house and grabbed a bowl and filled it with water, went back outside and put everything in there. I think I'm safe for now, but wow. All I could think was...
'Wow, the internet is going to love this'.