3 replies to this topic

[Garry S]

I'm overhauling some motors, main Parma Deathstar and such.  Armature end play is typically .010-.015, is this acceptable or should I be shimming for tighter tolerance?  

 

What is the minimum, and what are the performance advantages?

 

Thanks in advance,

Garry

[mreibman]

Well, you don't want it to be so tight that it binds up, as per captain obvious.

 

I would typically want to see abut .005" and be happy.

[Eddie Fleming]

Getting the arm centered in the magnets is more important than the amount of end play (within reason). You don't want the magnets pulling the arm up against the bushing on either end. That is probably even more of a concern on bushing motors than on bearing motors.  

[Bill Seitz]

I agree with Eddie, the primary thing is that the stack is centered in the magnets. Otherwise, the motors seem to do well regardless of the endplay as long as the arm isn't binding. After centering the stack, I personally prefer .005 - .010, but can't say that improves the performance. The main convenience of limiting the play may be keeping the pinion aligned where I want it.