2 replies to this topic

[cademurphy]

Does anybody know what type of magnets will slow my Knex roller coaster car down? If so where can I get them? I need help(K)

[Maxlaam]

Rare-earth magnets along the track and a non magnetic piece of metal as a brake fin. The distance between the magnets and the metal fins is critical, means that they are very unreliable considering how loose the coaches ride the K'NEX track.

In the end you are not looking for regular magnets because they don't really slow the car down, the magnetic brakes rely on Eddy Currents demonstrated in this video from Jogumpie.

[Jogumpie]

I think the performance can be upped a lot by using coin magnets instead of cube magnets. Cube magnets are more useful for reed sensors.