Let's see.
The barrel of the cannon is a tennis ball can. (I don't know if there is such a thing anymore.) Remove most of the bottom, but leave enough of a ring to support the tennis ball. The fit of the ball in the barrel should be snug to avoid allowing pressure to escape around the ball. The fit of the ball to the hole in the bottom should minimize gaps to allow pressure to build in the combustion chamber.
Graft a soda can to the bottom. That's the combustion chamber. The top should be open to the "barrel". A small hole in the side is for injecting the fuel and ignition. We used lighter fluid.
Insert tennis ball fully into barrel. It forms the top seal to the combustion chamber. Squirt a little fuel into the chamber via the ignition hole. Let it evaporate inside the chamber to create an air fuel mixture. Put a lighter or spark --- wait, wait, wait --- POINT THE CANNON IN A SAFE DIRECTION, ->then<- put a lighter or spark to the ignition hole.
Foom! Watch ball.
Typically we would aim at a 45 degree angle for maximum distance. I think we got 30 yards with a good shot. Bloopers were shorter. Repeat with different fuel loads to determine optimal amount of fuel to inject.
(Don't do this during fire season, as it's possible to send a flaming tennis ball through the air if the combustion chamber is running too rich. Aiming this at someone is a very bad idea, as the velocity can be pretty high.)
My imagining of Ryley reading this post:
"blah blah blah blah blah blah it's possible to send a flaming tennis ball through the air blah blah blah"
i didnt make it beyond "combustion chamber".
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The barrel of the cannon is a tennis ball can. (I don't know if there is such a thing anymore.) Remove most of the bottom, but leave enough of a ring to support the tennis ball. The fit of the ball in the barrel should be snug to avoid allowing pressure to escape around the ball. The fit of the ball to the hole in the bottom should minimize gaps to allow pressure to build in the combustion chamber.
Graft a soda can to the bottom. That's the combustion chamber. The top should be open to the "barrel". A small hole in the side is for injecting the fuel and ignition. We used lighter fluid.
Insert tennis ball fully into barrel. It forms the top seal to the combustion chamber. Squirt a little fuel into the chamber via the ignition hole. Let it evaporate inside the chamber to create an air fuel mixture. Put a lighter or spark --- wait, wait, wait --- POINT THE CANNON IN A SAFE DIRECTION, ->then<- put a lighter or spark to the ignition hole.
Foom! Watch ball.
Typically we would aim at a 45 degree angle for maximum distance. I think we got 30 yards with a good shot. Bloopers were shorter. Repeat with different fuel loads to determine optimal amount of fuel to inject.
(Don't do this during fire season, as it's possible to send a flaming tennis ball through the air if the combustion chamber is running too rich. Aiming this at someone is a very bad idea, as the velocity can be pretty high.)
- mark 12-08-2011 10:53 pm
My imagining of Ryley reading this post:
"blah blah blah blah blah blah it's possible to send a flaming tennis ball through the air blah blah blah"
- jim 12-08-2011 11:20 pm [add a comment]
i didnt make it beyond "combustion chamber".
- dave 12-08-2011 11:23 pm [add a comment]