While many of us have played with magnets as kids (young and old) we most likely never could find much to really do with them.

We immediately noticed that if you have two magnets things got more interesting. Attraction and repulsion of the north and south poles of the magnets being most noticeable.  But we usually still didn't figure out a use for that feature. Moving one magnet with the other one under the kitchen table was fun though.

I decided to experiment with a few different electric motor designs as a learning experience with low input power. All these motors are based on electrical design knowledge that has been developed since 1832. 

There are many enthusiasts building small magnetically levitated motors. You can find videos of these motors on YouTube. The following link is to a "Mendocino" motor which uses rotating solar cells to power a magnetically levitated rotor shaft. The basic layout uses a stationary magnetic field with rotating coils on the armature. Solar cells rotate with the coils and do the commutating of the drive voltage. While these motors are unique they do operate on well founded principles.

http://www.youtube.com/watch?v=Ncx2eVpWUzw&feature=related

Another class of home built motors are "pulsed" motors which rotate the armature with magnets attached using a stationary drive coil.  Various methods are used to time when the coil is energized to keep the motor running.  The levitated motor I built which is shown on the left uses the rotating magnets themselves to trigger the solenoid coil drive circuitry as a blocking oscillator

The  motor uses many common parts from my pre-owned collection of stuff.  The lowest drive voltage this motor runs on is 0.6 volt resulting in 0.177 milliwatts input power. No trickery, just careful design design of the drive circuitry.

The metal 1/4" x 20 threaded bolt is being levitated by Neodymium magnets at each end of the bolt. In other words, the affect of magnetic repulsion is supporting the rotating parts in mid air.

The motor is running in the picture while being powered by a garden night light solar cell. The motor and solar cell were inside my house on an overcast day at the time! The solar cell was located just to the right when the picture was taken.

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Purpose of this site:

The purpose of these pages is to present the theory of how a levitated pulse motor works and describe how you can build one for yourself. I've learned quite a bit about building a stable levitating system and will I explain what I've learned in the "Magnet theory & rotor construction" article.

I also will [hopefully] debunk the over-unity claims that some people make for these motors when used to charge batteries.  You will NOT discover how to make a perpetual motion machine here or anywhere else I suspect.  But these motors are a great learning experience and will give you a good hands on understanding of practical electronics and magnets.

I will NOT attempt to teach you electronics as there are many sites that can be Googled that go into electrical theory and design.  Amateur Radio sites are a good source of common electrical designs.  Most have schematics and some have construction articles.

Talking Electronics has hundreds of circuits with explanations etc that you might find interesting.  There is a lot of good information there.  Resistor color codes, how the circuits work etc.

If I present some formulas or terms you aren't familiar with please use that as a reason to use Google to find out what they mean.  The math I use will be very basic to electrical design to keep the site geared toward non-professional experimenters.

I'd read all the articles I've presented here several times until you really understand what it's all about if you want to build one of these motors but aren't familiar with how to do it. 

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Hopefully you'll have most of the materials already.  But here's the list of  the major parts and where I got them from.

1. A base for your motor with a vertical surface.  I used a fiberboard like material that was originally a desk draw divider and a short length of 1" x 2" 90 degree angle aluminum for the vertical part..  Pieces of wood will work fine, or aluminum sheet metal.
2. Four rubber stick on pads to go under the motor base.
3. One 5" long 1/4" x 20 ferrous threaded screw. Mine had a flat blade screw driver slot in the head. A threaded rod can be used, the lighter the better.
4. Six 1/4" x 20 nuts. The ones I used are aluminum for lightness.  Steel is OK but heavy. Nylon would be best for low weight.
5. Two square 1/4" x 20 nuts.  These must be steel so the rotor magnets will stick to them.
6. At least sixteen, N42 or higher number, 1/2" x 1/4" x 1/8" Neodymium ring magnets. I got mine from eBay.  The seller was zillionsof.  A pack of 20 was $11 with free shipping.
7. Four 1/4" x 20 screws to hold stator magnets in place.  These can be any material although mine are nylon. Length will vary depending upon how you mount the magnets.
8. One 1/8" steel ball. Mine is from a small ball bearing.  Or some other hard pointed object like the end of a ball point pen.
9. Enameled coated magnet wire, 200' of AWG# 30, 75' of AWG#26.  My wire came from a sonar buoy and a TV degaussing coil.
10. A plastic spool to wind the magnet wire on.  Hopefully one of the spools the wire came on will have enough room left to rewind both wires on it.
11. Various small screws, washers etc. All my hardware is either stainless steel, aluminum or plastic (nylon).
12. A small solar panel.  Mine is a 3.25 volts at 30 ma panel from a garden night light.
13. If you want to be able to disconnect parts of the wiring you will need some plastic connectors.  Mine came from scrap computers.
14. Several other metal parts which are not absolutely necessary for the eddy current generator to stabilize the free end of the rotor shaft.

NOTE:

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