Back at the dawn of the Iron Age (when I was just a kid) we took a lot of pride in manufacturing cannons in the 9th grade General Metal shop class at the local Junior High.
Mr. Beatty was the instructor and dedicated to imparting wisdom to any accepting vessel. He's get so wrapped up in explaining stuff to one or two kids that he overlooked many things the rest of us were doing right there in the fully functioning machine shop.
His dedication to improving the wisdom of the few allowed those of us less inclined to learn things and more inclined to make stuff essentially free access to the lathes and milling machines without a great deal of oversight.
None of us lost fingers or eyes, but we did manage to turn any number of cannons--mostly out of 1" round stock. We'd drill a 1/4" hole through the round stock about 5" from the end, tap it, and run a threaded rod through. We'd then cut the rod on each side and what remained formed the axis of the fulcrum to raise or lower that which was to become a cannon. Then we'd drill a 1/4" hole about five inches deep into the round stock to form the barrel. We'd turn a taper from the barrel tip to the butt and when all that was done, we'd turn a stylish knob at the butt end, drill a touch hole to ignite the powder, and the result was an historically inauthentic but fully functional 6" cannon.
In those days, black powder was available at the local hardware store to anyone with the necessary couple of bucks to buy a one-pound can. And a one-pound can would propel a huge number of 1/4" ball bearings, one at a time, into imagined enemy forces or into real cardboard boxes.
We may have even made a .22 zip gun or two for personal enjoyment--but I'm not saying. What I will say is we had great, good fun with those little cannons.
Some of the guys made carriages in wood shop, complete with wheels and miniature tow rigs, to go with the little cannons.
I have no idea where mine ended up. I suspect it was discovered by one or both parents and deposited in the trash can. My parents paid a bit more attention to what their kid was up to than did Mr. Beatty. And they had a better feel for the sort of trouble I could get into.
Hadn't thought about that in years. Thanks for a stimulating walk through my personal history, Mike.