Phonoland

What the heck happened here?

That's how they balance armatures. After they put the windings on they put the armature in a jig if one side is to heavy they take metal off so it turns true.

You might want to polish the commutator bars(copper strips on the armature) with some ScotchBrite or similar while you have the thing apart. No steel wool, tho. It can leave conducting residue that will cause you some grief after re-assembly.

-Jim

IMHO, there is no need to polish the armature--Ron Rich

Fred is correct re the balancing dimples.
From my old motor and transformer days when these were done by hand the coils had slight differences even after being wound on the same former, and of course when they were fitted in the armature there were slight differences so it was easier to balance the total armature.
It is almost like balancing a wheel but on a motor you can not add weights.

Regards
Alan

Alan Hood
ami-man
UK

Thanks guys!