coils

[ricksure]

After determining number of magnets to coils and number of turns of wire, is the

coil thickness done by trial and error? I would guess after building a few it

gets easier to "guess".  thanks for any insight Rick.    

[electrondady1]

generally speaking , the coil thickness is the same as your magnet thickness.

[finnsawyer]

Another rule of thumb seems to be that the coil diameter or width is twice that of the magnet diameter or width.  This then determines the rotor size, and given the wire size and number of turns it also, in effect, determines the coil thickness.

[hvirtane]

The coil size should be such big that the magnet can go inside the coil.

in the above picture the magnets are too near each others. Some people are of the opinion the distance from a magnet to the next magnet should be about the width of the magnet.

- Hannu