Magnet catapult

Hobbyists can now re-enact battles of the ancient world!
Author: Rob Gallagher, United States
Online since: 07/04/2009, Number of visits: 254594
Opposite poles attract each other, like poles repel - and it is this repulsion that can be harnessed, for example with this magnetic catapult.
After watching a period film about the siege of the Masada fortress by the Roman army, I too wanted to build a catapult.
For this purpose, I used the strong repulsion of two large disc magnets. 3 possibly options are linked below.
Damaged juggling balls
Damaged juggling balls
I built this shooting device from red oak. On the left, near the magnets, I placed brass fittings and on the right I put steel nuts and bolts near the joint.
For "ammunition" I used juggling balls.
The magnetic catapult shoots the juggling balls to a distance of about 3 metres! As you can see in the picture, the balls burst due to the strong impact.
I had a lot of fun with this little project.

Addition 2018

YouTube user RLScience also built a mighty magnetic catapult – even with two arms. For that, he used the repulsion of 3 Goliath magnets. In his video, he explains the assembly in detail (in German only).