Table saw motor brush question

Find a replacement brush and burnish the commutator with copper cleaner from the kitchen. If there are any commutator bars that feel rough they can be smoothed with a very fine file. If that doesn't help you may have to replace the motor or find a [rare] motor repair shop that will rebuild. Bugs

What is a commutator?

The area of the armature shaft assembly that makes contact with the brushes.

has nothing to do with a potato :-D

The chipped brush is not an issue. Why the brush chipped is an issue. It could mean that the armature is gone short (look at the commutator for a 'burnt' looking bar that may also be deformed). Could mean that the bearings are sloppy and the armature is vibrating. Or it could be that the brushes were just sticky and the motor needs a good cleaning.

Pete

For cleaning it would that copper cleaner mentioned by Bugs be a good idea?

I just realised that I didn't mention the why behind the brush not contacting the motor. The copper wire that comes out the back of the brush had been twisted up (like how you would twist up a rope to make it shorter), and that was preventing the spring from pressing it into contact with the commutator (did I use that correctly?). Once I untwisted the brush, the wire loosened up and everything worked as it had been.

I'm kind of hesitant to do too much to this saw, since it's over 30 years old, and I can't afford to purchase a new one, so the less I monkey with its guts, the happier I'll be. If, however, giving the commutator and the rest of it a cleaning would make it run better, I wouldn't mind delving into it.

Thanks for everyone's responses!

-Nathan