and if so, how?

never tried it but good question ill check further into that my self ive got an old motor ill try it

Yes, they make a "stock motor" lathe or you can remove the arm from the can like normal. I think I understood you.

no i think he means one of the silver sealed endbell motors with the built in brushes. these motors to my understanding are NOT! rebuildable. they were designed for a cheap means of getting kids into the hobby. They are also verry low in power a basic tower hobbys rebuildable stock motor would easily out perform these. the only sealed endbell motors that I know of that are anywhere near decend are some of the traxxas ones. and I have never tested one so I personaly do not know. but as far as truing a comm while its inside the motor DONT DO IT! I used to have a comm lathe that would true the arm while it was still inside of the motor. such a PITA. and the coper chips coming off the comm would arc and spark because remember your turning a conductor inside of a magnetic field this creates electricity. so the first few times it would scare the crap out of me. Also it was verry hard to properly clean the motor of all the copper chips after lathing it like this. so my suggestion get a cheapie tower hobbys or similar rebuildable motor for 10-14 dollars and save yourself the headache.

HOPE THIS HELPS
Sean Scott

If you are talking about the older stock motors that are not rebuildable, there is a stock truer from C&M Team Cobra for those. If it is the ones with out access to the brushes, then I do not think you can, but I have never tried.

some of those are designed to be SPEC motors and are not meant to be rebuilt...

you can turn the com on any motor. you may have to bend the tabs on some old non-rebuildable stockers and closed endbell motors (the silver can ones). then pull out the com. once turned clamp the tabs back down. the only downside to this is the motor would NOT be legal for racing after its rebuilt but there is nothing wrong with continuing to use it as a practice motor or basher motor.

you can turn the com on any motor. you may have to bend the tabs on some old non-rebuildable stockers and closed endbell motors (the silver can ones). then pull out the com. once turned clamp the tabs back down. the only downside to this is the motor would NOT be legal for racing after its rebuilt but there is nothing wrong with continuing to use it as a practice motor or basher motor.

thats what i was gettin at is that its illegal once u cut it...

There was a truer in the mid 90's that had a longer thinner cutter,
which when you remove the brush hood on one side gave acsess to
the comm and gave a great cut without taking the endbell off.

Best and easiest idea:
Get some Brasso from the hardware store, and one of those grease syringes (monoject is the name I think). Suck some Brasso into the syringe, and put a small amount onto the comm by going thru the vent on the motor. Put a pinion on the motor and roll the gear back and forth. The Brasso should turn black quickly. This will remove most of the junk on the comm, and also help to seat the comm and brushes back together as much as you can without a lathe. Make sure to throughly clean the motor with motor spray to get all the Brasso out.

Best and easiest idea:
Get some Brasso from the hardware store, and one of those grease syringes (monoject is the name I think). Suck some Brasso into the syringe, and put a small amount onto the comm by going thru the vent on the motor. Put a pinion on the motor and roll the gear back and forth. The Brasso should turn black quickly. This will remove most of the junk on the comm, and also help to seat the comm and brushes back together as much as you can without a lathe. Make sure to throughly clean the motor with motor spray to get all the Brasso out.

Great idea man!