My Replication of the Adams Motor
mpeg video (7 mb file recommend broadband connection)
I wanted to quickly test the claims of this device and chose the Bedini model, probably the simplest version around. I needed a rotating nonmagnetic plater using a low-friction ball-bearing. I found a garage door pulley wheel at Home Depot that looked suitable and then picked up the following hardware:
3" long 1/4" diameter hex-head
bolt with a 2" unthreaded shank,
Magnets? I bought a bag of 10 from Radio Shack, 3/4" x 1 7/8" x 3/8" domino-sized ceramics that are quite strong. I enlarged the central hole in the plastic sanding disk to clear the 3/8" bolt and pulley hub. I then glued the disk to the pulley with industrial strength contact cement. Once dry, I cemented the magnets with all north faces up at 90 degree intervals on the plastic disk as shown here:
As you can see, the pulley-disk-magnet assembly
was bolted to a 3/4 x 4 1/5 x 9 1/2" pine board.
I mounted a 4 1/2" long piece of 2x4 as shown so that it just cleared the rotor using 2 1/2" long wood screws from the bottom.
The aluminum angle was screwed to the upright 2/4. Now it's time to wind the coil.
The coil was wound on the 1/4" bolt
by first puting a single thickness of black electrical tape around the
I tried to bunch most of the windings near
the bolt head where most of the coil would be in the strongest part of
the magnetic field.
While at the Shack, pick up:
The TIP3055 switching transister and heat sink (which I later realized was totally unnecessary) were mounted to the end of the base board with a small wood screw. The rest of the parts were then soldered together with 22ga vinyl insulated wire following this schematic:
As you can see, Bedini's design is a vertical
ferris-wheel rotor arrangment mounted over a fixed vertical pole stator.
Next, scrape the ends of the four copper stator leads and tin with solder. Next take the two 22 ga (thicker, heavier wire) leads and determine what polarity is required to produce a repulsive field. Touch the leads to the 9V battery terminals until you see repulsion, then mark the lead connected to the positive battery terminal when the repulsive effect was produced. Solder the red positive battery terminal lead to this 22 ga wire. Solder the other 22 ga lead to the emitter lead-diode-black negative battery lead-ground connection.
The smaller 26 ga wire on the same side
as the + 9V lead, goes to the Base terminal resistor(s).
Starting the Motor
I quickly measured the voltage drop across the battery under load. It was just at 7v at 2:43 pm 9-28-2004. Within a few minutes the battery case was noticably warm to the touch. But the coil, drive wires, and transistor remained at room temperature of even slightly cool. The battery voltage steadily dropped over the following 70 minutes that the motor ran before finally shutting down with a final voltage of 5.5v.
I have doubts, however, with the current circuit that there would be any over-unity achieved in that back-EMF doesn't appear to be collected, at least by the battery. Tim Harwood and John Jankowski's excellent treatment of the Adams Motor imply that the back-EMF is used by the stator itself to enhance its repulsive field. In that case, my coil design might need to be optimized: better core (Bedini suggests using multiple lengths of welding rod), more turnss (some designs specify 450-800 turns). Bifilar windings are mentioned often, but simply winding both wires together doesn't really qualify as bifilar since they constitute two separate windings.