The armature and housing assembly are the only two
components repaired by restoring them to serviceable condition.
other components and repair parts are replaced when inspection indi-
cates unserviceable condition.
b. Resurfacing Commutator.
(1) Install commutator end bearing on armature and mount in
lathe with armature turning center in place on bearing (fig. 5-13).
Do not mount armature in shaft centers.
(2) Measure diameter of commutator to make certain it can be
Do not attempt
safely turned to minimum diameter of 3.220 inches.
to refinish commutator reduced by previous resurfacing to less than
(3) Secure and sharpen cutting tool for commutator work (fig.
Position cutting tool against commutator as shown in figure
Make certain tool is sharpened by final honing with hard,
(4) Take light cut across entire surface of commutator with
armature rotating between 600 and 800 rpm (fig. 5-13).
is not severely worn or pitted, first cut should renew the entire
If commutator is badly worn, take additional cuts until
entire surface is renewed.
Carry each cut across entire surface
without stopping, and remove no more than 0.005 inch of material in
any one cut.