Latest: No back torque generator.

[Paul-R]

If the magnet is the conducting disk as well there is no way the force is caused by the current flow on the disk. Think about it this would violate newtons third law...

I shouldn't get too hung up about violating the Third Law. Its been done already with all those gyroscopes producing a reactionless force.
Paul.

[Low-Q]

Why do you think that when the magnet and conductors are spun together, a current will result?

The current results only from the Lorentz force on the charges which is F=q*v|B where v is the speed of the charge relative to the observer. A bulb on the rotor having a null speed relative to the conductors, no current can be expected. It is the same thing as the Faraday disk: brushes at rest are needed for a current to flow in the circuit.

This is also what I think. There must be a relative motion between the coil and the magnet. But I think it is right to build it with an LED to determine if it works or not - most people, me included, must learn that way.

If you some day want to collect that power outside the spinning system, you must use brushes and a fixed wire. Then it will collect current, but that current is made in the fixed and still wire outside which is "bombarded" with the rotating magnetic field... That is how I understand it anyway.

Time will show. But this far I have seen only 3D drawings and plenty of text that is some how convincing, but still are open to question.

Vidar

[broli]

This is also what I think. There must be a relative motion between the coil and the magnet. But I think it is right to build it with an LED to determine if it works or not - most people, me included, must learn that way.

If you some day want to collect that power outside the spinning system, you must use brushes and a fixed wire. Then it will collect current, but that current is made in the fixed and still wire outside which is "bombarded" with the rotating magnetic field... That is how I understand it anyway.

Time will show. But this far I have seen only 3D drawings and plenty of text that is some how convincing, but still are open to question.

Vidar

The collector wires are stuck together positive and negative so they are invisible to the chaotic field of the magnets.

[lumen]

You can make a homopolar generator with magnets the same size as the disk. Sandwich them all together so the magnets are attracting thru the disk.  Now spin the whole thing. You can draw a current from the axle and the disk edge (or even the magnet edge), and you can arrange your leads so that the only place a conductor cuts flux lines is in the radius of the disk connecting the axle and the edge contact. If the flux was spinning with the magnet, even this radius wouldn't be cutting flux and so shouldn't  generate a voltage.
The reverse situation with "simplest" homopolar motors also illustrates that the flux need not rotate with the magnet. You can even use the magnet itself as the disk, and only the current path within the magnet (or on its surface) is producing a ponderomotive force on the disk--the edge brush doesn't feel a push if you approach the disk from the right direction.
OR does it?

This depends where you believe the flux lines end. The center shaft causes no addition to the load because the flux lines move away from it while looping to the other side of the magnet but the outer contact is the problem because any direction cuts the lines of force.
I have done the tests with the magnet spinning with the disk or just the disk spinning and even a stationary magnet and disk with only spinning contacts!

There is no way to escape the rotating field and the current will be induced in the external circuit or whichever is moving in relation to the magnet.
You already know if you rotate a meter with a large disk, no current will show, that's because the current is induced in the external circuit.
I had only one idea on how to escape this problem and I have not tried it..... yet.

[BEP]

And there are multiple disk rotating homopolar generators that use only the axles for output current, and these axles are, well, axial to the magnetic field until well clear, so no relative rotation whether or not the field turns with the magnet.

The common conversations about these devices never seem to touch on the above fact. The wire loop standing on a battery then on a magnet is so easy.

I agree with you about reaction. That's what makes it weird, or experimental error, or something. That's also why that Mylow fellow's motor can't be driven by the stators.

Perhaps not directly.
I hope we aren't drinking from the same bottle. Sure sounds like it. Good thing it is only Snapple.