Levitron: Playing with Magnetic Levitation

The Levitron can be a very difficult toy to use.  It can take quite a long time to get both the base level and the top properly weighted such that the top can hover in equilibrium.  After experimenting with the Levitron for hours in lab, we have compiled this set of instructions to help you use the Levitron.

When the base magnet of the Levitron is not level with gravity, the top will fly off to a side.  If the top flies off to the same side multiple times, your base is not level.

If the top flies to one side immediately, raise the peg on that side at least two turns.  If the peg is as high as it goes, you can lower the pegs on the other two sides.

You should keep adjusting the legs until:

1. 1. The top flies off to different sides each time, or
   

2. 2. The top hovers for a little bit and then flies off to the same side, or
   

3. 3. The top hovers and does not fly off.
   

If you reach (1), it is time to proceed to choosing weight for the Levitron.

If you reach (2), adjust the height of the pegs very slightly rather than two turns. Sometimes even half a turn is all it takes.

If you reach (3), congratulations, you have mastered the Levitron!

Now you have a level Levitron base!

It is easier to decide on a good weight for the Levitron by probing at the condition where the top is just a little bit too heavy.  When the top is a little bit too heavy, it will almost bounce on the plate but not quite lift off, before spinning out on the plate.  For this reason, you should approach the weight issue from the heavy side.

If you have never used the Levitron, the first thing that you should do is put all of the weight on the Levitron.  You will most likely find that the top will not lift off the plate.

If the top does not lift off the plate, cut the weight in half.

If the next time around, the top does not lift off the plate and is not close to lifting off the plate, cut the weight in half again. If it lifts off the plate too strongly and the plate is mostly level (see leveling instructions), increase the weight to the halfway point.  Continue this binary search until your top either almost lifts off the plate or hovers for a little bit before flying off in random directions.

If the top does either of these two things, it is time for small weight changes.  If the top is too heavy, try removing a small weight or extra o-ring.  If the top is really bouncing on the plate, it will probably only

need one o-ring removed.  If it is barely too light, try adding the smallest weight or o-ring.  The o-rings make a bigger difference than one would expect.  Eventually, you will find the correct weight.

If you have used the Levitron before, start with the weight that was previously on the top.  Use the same search method as outlined in the previous section.  The magnetic field is temperature dependent,

and so the necessary weight is as well.  If it is a colder day, you will probably find yourself adding weight.  If it is warmer, you will probably need to remove weight.