V-gate motor
designed by Robert Calloway (see his web site.)
 


Here I will describe my rebuild of Robert Calloways V-gate motor.

FIG 1 This is how the original looks.
I decided to make a bigger version. Since weight is an important issue, I think that the percentual weight on a bigger device is easier to control: One little screw in the small version has a bigger impact than the same screw has on a large version of the device.
First I made a check list with the parts I needed, to make a start:
  • A carbon fiber bicycle wheel
  • The longest neodymium rod I could find
  • Ferrite rods that should be cut in smaller pieces
  • Plastic screws to mount the pieces of ferrite on a rim
Secondly I made a check list with things I had to solve:
  • Cutting the ferrite rods in smaller, equal pieces. For this I bought
    • A holder to mount my Dremel on my lathe
    • Diamond coated cutting wheels for the Dremel
  • Making plastic cups to hold the pieces of ferrite (a job for my 3d printer>
A search on the internet tells that cutting ferrite is very hard, almost impossible. But when I mounted that long ferrite rod in my lathe and had it rotate at 1200 rpm and at the same time had my Dremel mounted in the tool holder, rotating at 8000 rpm, I had a very nice cut.

 
The cups that my 3d-printer are printing fit tightly around the ferrite rods. Cups with ferrite have a treaded rod at the bottom and will be attached to the rim of the wheel.
 (One done, 299 to go)
 A peek into my workshop.
As Robert Calloway pointed out: testing the setup in order to find the best distance between the magnets.
So here I prepare for a test rig. The ferrites are still loose from the cups.