6061 shaft to 6061 rotor interference fit or better?

[NeoRules]

So I have 6061 rotors with neodymium magnets in them.

I want them to not spin on the shaft so at least an interference fit.

I believe that would be .005 and freeze the shaft first since I can't heat up the magnets (275 degrees) without damaging them or the glue.



What other methods can I use knowing the shaft is 1 inch and the rotors are 1/2 inch apart.

Would a keyed shaft be safe at 20K rpm?

Or I could limit myself to much lower RPM.
But the only tools I have at my disposal are a Bridgeport CNC (Series 1 retrofit) and my desire to succeed.
So splining a shaft and the rotors is probably beyond my level but I can always use an online shop if I have too.

I have done well at all other aspects of the motor (speed controller build, winding fabrication etc.).

Thanks JC

 

[markba633csi]

You might want to do around 3 thou if you plan on using regular (not dry) ice/fridge
I would do a test piece first to see how much time you have to fit things together

 

[pontiac428]

Without knowing how much torque you are trying to hold, it all sounds good from here. You are not likely have any issues running a keystock, unless torque exceeds the shear strength of the key (or more likely the 6061). External splines are not particularly hard to machine on a mill, but internal splines will lock you down without having a shaper/slotter head or making broaches. Square drive is another easy to implement solution that is easier to accomplish in the shop- a four spline system.