Bob La Londe wrote:

Is there any electrical reason not to put the bearings in a metal bushing
instead of the nylon one?


Not if the frame is grounded. Otherwise, it's an attempt to isolate
the frame from the armature. that will prevent a shock while using the
tool, but could kill you if you touch the motor shaft & a good ground
when the insulation fails.


--
You can't have a sense of humor, if you have no sense.