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Need Help Synchronise Two Spinning Magnets

Discussion in 'The Projects Forum' started by roonyroo, Jul 18, 2012.

  1. roonyroo

    Thread Starter New Member

    Jul 18, 2012
    Im trying to spin a magnet using another magnet attached to a small fan

    The problem is the magnet spins fine, at low speeds, but if I increase the speed, the magnet attached to the fan overshoots the 2nd magnet

    One magnet is attached to a small fan, the other magnet is attached to a cardboard circle attached to a stick ...

    So how can I keep the 2nd magnet attached to the stick spinning at a higher speed, using the magnet attached to the fan?

    Is there a formula I can use to predict the amount of magnetic force required to spin other magnets at high speed?
  2. wayneh


    Sep 9, 2010
    Boy, is there! Physicists are nothing if not fond of formulas.

    But really your problem is just inertia and resistance. You need the second magnet to spin very freely on a bearing and I think it will eventually speed up enough to get "caught" by the driving magnet. The key is that each pass of the driver must give more acceleration to the passenger than is absorbed by spinning resistance.
  3. Markd77

    Senior Member

    Sep 7, 2009
    Stronger magnets or decrease the distance between them. Also if you can use more than one magnet on each disk (equally spaced) that would be much better because it balances the weights and also off-axis forces from the magnets.