Thought experiment: Designing a Leslie rotor stop (front firing position)

[BrownIsound]

I am considering adding a modification to my Leslie 125 to have it so when you power off the rotor, it will stop with the rotor opening facing forward.

Reasoning: so when it is "off", its speaker can still act as a volume boost with my other/main amp. When the rotor stops now, the volume boost is variable, likely due to the random direction and phase issues with the main amp when it stops.

So my crackpot idea is to have some switching mechanism that turns on an electromagnet next to the rotor when the power to the rotor is off, and a piece of magnetic metal on the rotor, with an equal counterweight on the opposite side made of lead, or some other nonmagnetic metal, so it will stop at the desired position.

So, wanting the simplest switching, lowest noise, correct strength magnet for this purpose...I have no clue with designing something like this.

I suppose an alternate method would be some king of physical stop...like a solenoid that triggers a pin to stop the rotor with another pin on it at the correct position, though I would want something soft so it wouldn't cause damage with an abrupt stop...seems simpler but too abrupt.

This is a Leslie 125, so only the one bottom drum rotor, but it is the heavy wood one (not the styrofoam one).

A bonus would be designing in some kind of delay, so the rotor would slow down naturally for a few seconds before the stop is triggered.

[Bash]

I like the idea, but I think you'd need a very strong magnet for it to work reliably.

[RedneckSage]

Perhaps it may be easier to make a mechanical brake using Neodymium magnets. The 125 uses a very lightweight styrofoam rotating horn (rotor) that you could likely just simply attach a magnet to and then you could brake it by using a piece of ferrous metal attached to an RC car style servo motor that would rotate into close proximity of where the magnet will be passing by as it spins. It would have to be very close to the spinning rotor for the magnet to be able to attract to the steel bar but it would be doable. You could actuate the servo with the foot switch that you use to control the spin of the rotor.