Magnetic coupled motor vs a shaft sealed motor.

[Erik102696]

Iv been looking really deep into shaft seals and im starting to rethink my approach. Have any of you worked with magnetic coupled thrusters? What are the pros and cons of this approach.

[rossrov]

Hi Erik. Personally I think that mag-coupled is alot harder to make. Part of this is that tighter tolerances are needed than say lip seal and oil filled. Making an effective mag-coupled unit without a lathe or at minimum a 3D printer like member A_Shorething has done would be tricky. Magnet assemblies need to be balanced or vibration will occur, and to avoid "slipping" between motor and prop the magnets need to be quite close. You also need to address the cooling requirements.

If you decide to go the magnetic route, then try to keep the diameter of the magnet wheels as great as possible. This way you can afford greater magnet gap (through the motor enclosure wall) than small diameters, as there is less torque to transmit. By the same token, higher revs are better than excessively geared down.