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Bench Tests: Commutator

  1. Clean surface and polish with No. 400 sandpaper if required. If surface is scored, out of round or pitted, turn commutator in a lathe.
  2. Maximum commutator runout and minimum diameter of commutator must not exceed specification after turning. Refer to the COMMUTATOR SPECIFICATIONS  table.
    COMMUTATOR SPECIFICATIONS

    Application Maximum Runout Minimum Thickness
    All Models .016 (.40) 1.06 (27.0)
  3. 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.