hello i have a 1995 milltronics that i have had some Y issues with the servo motor. I had the servo motor rebuilt by a local starter place they told me they had to hunt down a set of 32volt brushes and had to cut them to size to make it work. the issues is you can clean the armature out and sand it with 2000 grit paper and it will run fine for 20 hours then it will start vibrating very bad in the Y axis. should i send this servo motor to a person who specializes in servo motors? i dont think the encoder is this issue because if you clean the motor it will last for 20 hours before the symptoms starts again. Any suggestion would be great. Thanks joe
The next time it happens, try this: power down, swap the X axis drive card with the Y axis drive card. Try it again, see if the noise stays with the Y motor. This will isolate either the motor or the drive card as the problem. If the noise moves, the card is the problem, if not, look at the motor.
If it is the motor, you may want to pull the motor brushes - make note of which brush comes from which holder and the orientation of each brush in its holder. Mark the cap's position on the motor and re-move it from the end of the motor. Mark the encoder coupling, and remove the encoder mount, don't lose the white plastic coupler piece.
Mark the position of the tach plate and brush assembly and carefully remove it. Don't damage the brushes or the wires.
Use compressed air to blow the carbon dust out of the motor. Blow through each motor brush holder. Clean both sides of the tach plate with electrical contact cleaner or alcohol.
Re-assemble the tach plate back to the same place you marked, put the encoder back matching your marks. Put the cap back on, once again matching your marks.
Many times, this process eliminates the growling sounds from motors.
Remember to re-time Home Position when installing the motor.