Minibot magnets ?

[Mr. B]

The first "small" minibot that we built used 2 hard drive magnets and worked very well. We used nail polish remover to get the steel brackets off and mounted the magnets with small screws. The next "small" minibot used (1) 28 Lb. magnet from KJ Magnets. The last mini that we built has 2 magnets from KJ --a 28 LB and a 16 Lb. The third minibot is less likely to fly off the pole and damage itself.
My favorite is still the first. As for speed, it is hard to tell, I think the first one is the fastest but when it hits the top, it flies off the pole.

[Cynette]

Originally Posted by Mr. B

The first "small" minibot that we built used 2 hard drive magnets and worked very well. We used nail polish remover to get the steel brackets off ...

Nail Polish Remover? We milled the steel backing off of ours. I wish we'd thought of nail polish remover!

[spacepenguine]

We used hard drive magnets in our 4th revision minibot. We had to use 5 of them through due to how thin they are. It held well since the minibot was just about 2lbs (~1sec). I just used a screwdriver and hammer to tap the magnets off the bracket =P

[Jeffy]

Originally Posted by spacepenguine

I just used a screwdriver and hammer to tap the magnets off the bracket =P

Did you do any constructive testing before and after removal to see if the tapping decreased the magnets effectiveness?
Next to extreme heat, hitting magnets repeatedly is the worse thing you can do to a magnet. I wouldn't advise this to anyone.
(but if it worked for you, well done!)