Now, now... don't go getting all excited. Yet.

First, electrostatically powered motors are nothing new. I've shown both a corona/charge motor similar to this one but using an actual bearing and a horizontal rotor, and a classic Franklin-style motor with an enhancement of my own, both running on the output of the Moore's Dirod electrostatic generator, some years ago.  And for a real blast, I designed and built and demonstrated an electrostatically-powered Tesla Turbine/motor, which needs a bit more power to spin, so I run it from the output of one of my Bonetti machines.

Second, I stuck a big fender washer to the ring magnet on the eraser end of the motor in the video above. Now that there is a conductor "cutting" magnetic field lines, there is eddy current generation in the big washer and so this puts a drag on the system and the maximum RPM goes down, to about 2400 RPM. I can get a detectable homopolar voltage by contacting the washer in the right place, but since the radius of the washer is small and the ring magnets only weak ceramic ones, the voltage is tiny, on the order of tens of milliVolts, and of course this is into a very high impedance load as well. I very much like the idea of using the axle point as the central contact for a Faraday dynamo, but when I put the large washer on the pointed end of the motor the eddy and mechanical drag was so great that I could only get a few hundred RPM out of it. This washer is magnetic though. If I can find a copper washer or make a copper plate that will probably work a lot better.

Third... the current at 6.4 kV to power this motor is very small, the power supply is essentially seeing an open circuit at the load. I'm putting about 5 watts DC input to the HVPS but this translates to much less at the rotor because of the low corona current (high impedance output load.) 5 Watts is basically the quiescent draw of that power supply, no load on its output. You could say that this motor "runs on voltage" because it is the electric field of the charges that pulls the rotor around, not an electromagnetic interaction (caused by current) like normal motors. There is of course some current flowing in this motor but it's small.

Finally...for now... thanks for posting a link to my video! Enjoy, contemplate, discuss.

TK:

That corona photo is very cool.  I am enjoying this line of experimentation that you are doing here.  I have nothing to add but now that I have posted, I can follow this work.

Keep it up.

Bill

The shimstock or copper strips used as "blades" can be vastly improved in performance by serrating the edges with a couple of passes of pinking shears, making a series of little points along with the sharp cut edges. You can't do this with razor blades! But you can take, for example, the braided shield from a bit of coax, fray it out to make a fan of individual strands, and this will work very well too.

This also works with the electrostatic "lifters". If you serrate the lower edge of the bottom skirt they will lift much better (and also use more current from the source). I've pointed this out many times in various "lifter" threads but nobody seems to want to do it... probably because it reinforces the "ion wind" explanation of the operation of lifters and is contrary to the TTBrown capacitive thrust hypothesis.

Also, simple pivot bearings made from tiny test tubes or hardened setscrews are excellent bearings for these kinds of motors.

The Poggendorf style motor works by slightly different principle than the edge-blown motors like my MagLev, or the Tesla Turbine in this clip:
http://www.youtube.com/watch?v=ir9RIsXzmzY

Heh. Beware the flicker!

Unfortunately, at 15 kV, even 10 microamps still represents a lot of power, much more than the rotor itself is dissipating, probably. I think I am getting substantial eddy current braking in the brass discs even at the spacing shown in the above video.

I've started to make some refinements to the construction. I've replaced the pencil with a phenolic tube, with an aluminum point insert that I made with a drill and a file. This took care of a lot of the radial out-of-balance and makes a more stable axle for mounting the ring magnets and rotor disk and any homopolar components I might decide to test. A brass bushing replaces the improvised solder weights for longitudinal balancing.  I also made a better adjustable mount for the electrodes. Next will come a proper base for the suspension system magnets and mirror.

I've already broken the old speed record, having gotten up to 5870 RPM with the new axle and the 15 kV supply.

Does this count as a pulse motor? I'm giving it one Longggggggggggg pulse of DC.........

I wonder if a conductor disk placed close to the rotor might collect spill off power from the corona?

The title of this thread is a bit misleading, this seems to be an electrostatic motor. Another property of a homopolar motor is that rotation direction depends on current direction, correct me if I'm wrong but I don't think the direction of rotation changes when current is reversed?

Broli, the videos don't show any testing of the homopolar components yet, and they aren't even installed on that last photo. But I have tested a couple of configurations and have gotten a few mV of homopolar output into a high-impedance voltmeter.

I cut out a disc from brass shimstock and mounted it right up against the rear ring magnet. I made a couple of small carbon-fiber brushes that have high conductivity and a very gentle touch, and using these as probes against the brass disc surface at the periphery and close to the center, I could detect the voltage, very small, but with the correct sign for the magnet and probe polarities and direction of motor rotation.

Unfortunately I also noted a couple of other things. First, the homopolar voltage is very small. The conductor path length is short and the magnetic field of those ceramic ring magnets is really weak. Second, the strong suspension magnets (these are epoxy-coated, very thin, N52 or even stronger, special purpose NdBFe magnets) create fairly strong eddy current braking on the brass disc when it is so close to the suspension.

I tried another larger brass disc glued to a plastic disk for rigidity and spaced further away from the suspension, but I couldn't test it for homopolar activity because I don't have another suitable magnet for it. Still, it produced enough aerodynamic braking and possibly also still some eddy braking that it slowed the top speed of the motor by half, down to a bit over 2700 RPM. I have some stronger ring magnets coming soon, I hope, so I'll be setting up for more homopolar trials when they arrive.