I just finished a run of 2/3 scale Perpetual Motion Holders. These are more practical freestanding desktop versions that can perform all the same functions as full size versions. Without the wire these unites weigh approximately 7.5lbs.
The additional coil includes a core of the same length to perform Leedskalnin's AC tests and his Best Machine demonstrations.
If you would like to wind your own coils (includes the 3 spools and additional core piece) the cost for units without the wire is $300 including shipping inside the US..
For units with the coils the cost is $500 including shipping inside the US. The main 4" coils are wound with 16 gauge magnet wire. The extra coil is wound with 28 gauge magnet and is used to perform Leedskalnin's experiments highlighted in Magnetic Current.
These units were water-jetted out of 1" plate cold-rolled steel. The faces were then machined to save on polishing time... The spools are cut and lathed by me using 6061 aluminum.
If you're interested in purchasing one contact firstname.lastname@example.org
That's one impressive PMH!
Very nice job...
What about the material structure in thise two cases?
I've wondered this myself and it would be interesting to test one of each to see if there are any notable differences. Obviously there is some difference because the structure is being stretched when bent. Here is an interesting article on the subject:
I've made several of these over the years, but all out of plate either milled or waterjetted. Soft iron of Ed's day is hard to come by in the US so I've always used cold rolled steel. The difference in hardness between these two is another thing to ponder. Soft iron it seems would have an easier job of pushing the magnets out leaving no residual magnetism at all. With cold rolled there is small amount of remaining magnetism, but it can be easily removed by zapping the unit with opposite charge.
These rather large 1.5" C shapes I made to demonstrates Ed's atomic model have a tremendous bonding effect. In this arrangement it's basically a circular PMH, but I call it my homemade particle accelerator.
It's hard to tell if the exceptional bonding is simply due to the overall mass, or because it's a more gradual curve than a normal U shape PMH...
I've been charging these arcs with one coil... The compass needle will move gradually as you move from pole to pole along either arc depending on the position of the coil when the charge was induced. One pole can be made more powerful than the other by sliding the coil closer to it. If the charge was induced at the equator of the arc then the poles are equal in strength.
Sweet pro work.
A nice picture to behold.