Bench Tests: Commutator
- Clean surface and polish with No. 400 sandpaper if required. If surface is scored, out of round or pitted, turn commutator in a lathe.
- Maximum commutator runout and minimum diameter of commutator must not exceed specification after turning. See the COMMUTATOR SPECIFICATIONS .
- Commutator mica undercut depth on all models should be .016-.031" (.40-.80 mm). Minimum mica undercut depth is .008" (.20 mm). If not within specification, undercut with a hacksaw blade to standard depth.