Trebuchet
Posted: Sun Mar 30, 2008 12:31 am
Another toy in use over Easter weekend... I made this trebuchet over the previous winter because I was bored and wanted to make a larger version of my 16" tall treb.
This won't throw any cars or pianos, but with 200 lbs of lead as counterweight, it will launch a soccer ball 55 yards, 400 lbs will send it 90+ yards. It can also send an 8# bowling ball over 80 feet in the air and that far again. The basket will hold 600 lads of lead, but I just don't have that much, yet.
I used this at an elementary school's midevil days festival to launch candy threw the air- it send grapeshot anywhere from 5 to 55 yards away. A friend also used it at a nearby scandinavian days festival.
[youtube][/youtube]
Specs: 12' long, 10' wide, fulcrum at 66", arm is (if I remember correctly) just over 10' with a 4:1 ratio. Vertical drop is somewhere in the 33-34" range. Axle / pivot shaft at fulcrum is about 1.38 bar stock inside 1.25 galvanized pipe that has been honed out for a near perfect fit. I lubed it with lots of axle grease. Weights: see my how-to on smelting lead, I was making bricks for this that day. Sling is made from parachute cord, welded o-rings, and machine-stiched industrial straps.
Next I would like to do a floating arm, but these look cooler.
My 4 year old likes to help pull the trigger and load the sling.
This won't throw any cars or pianos, but with 200 lbs of lead as counterweight, it will launch a soccer ball 55 yards, 400 lbs will send it 90+ yards. It can also send an 8# bowling ball over 80 feet in the air and that far again. The basket will hold 600 lads of lead, but I just don't have that much, yet.
I used this at an elementary school's midevil days festival to launch candy threw the air- it send grapeshot anywhere from 5 to 55 yards away. A friend also used it at a nearby scandinavian days festival.
[youtube][/youtube]
Specs: 12' long, 10' wide, fulcrum at 66", arm is (if I remember correctly) just over 10' with a 4:1 ratio. Vertical drop is somewhere in the 33-34" range. Axle / pivot shaft at fulcrum is about 1.38 bar stock inside 1.25 galvanized pipe that has been honed out for a near perfect fit. I lubed it with lots of axle grease. Weights: see my how-to on smelting lead, I was making bricks for this that day. Sling is made from parachute cord, welded o-rings, and machine-stiched industrial straps.
Next I would like to do a floating arm, but these look cooler.
My 4 year old likes to help pull the trigger and load the sling.