My Catapult

Neodymium Powered Of Course

Opposite poles attract, like poles repel, and if you have really big magnets they repel a lot. 

After watching a History Channel show about when the Roman Army laid siege to the fortress of Masada I decided to construct a Catapult taking advantage of the repelling force of a pair of 2" dia by 1" thick Neodymium Magnets which have a pull force of 230 lbs. I built the launcher from red oak with brass hardware near the magnets and steel nuts and bolts at the pivot. The ammunition is beanbags.

Check out the video.

The Catapult launched the beanbags about 10'. The force at launch was enough to split both beanbags and spill stuffing.

All in all, this was a fun little project.