Perhaps if you tried the same mod with big ring Neo's instead of ferrite magnets, you could double the flux (or more). That would yield a better V/RPM ratio. Still fast, but on a small mill, might be closer to the ballpark.
Also a great illustration of how magnetic flux lines can be manipulated, with a little creativity. Steven Fahey
I think the shaft provides a much better flux path for the magnets than the air gap between the claws... effectively short circuiting the flux from claw to claw, rather than jumping the air-gap.
With the original electromagnet, the shaft "became" the magnet and the return path for the flux was across the air-gaps. The shaft in your configuration now becomes the return path instead.
Solving this problem (with a magnetically inert shaft)will increase the flux density between the claws air-gap making it the only decent flux return path.... increasing its effectivness markedly..... new shaft looks the ticket.
good use of old alts and microwave oven Joe.
.........oztulesFlinders Island Australia[ Parent ]
