Question about AC motor brushes

[KY_EnviroGuy]

12. Agree with RKP on no WD-40.

Do not sand on a motor armature or stator laminations because they're made of laminated steel sheet that are insulated like a transformer core. Just brush the loose stuff off (a stiff plastic brush like an old denture brush would be good).

You can protect most motor parts from further rusting by spray or brush coating (very thin) with clear acrylic paint and dry it well in a low-temp oven or under a heat lamp. Bake until you no longer smell solvent and the coating is hard. Be sure to not spray the brush commutator and bearings. High-temperature varnish is normally used for motors. WD-40 on a motor could cause a fire and it would be a dirt magnet.

But most importantly, do not submerge motor armatures or stator windings in anything. Nothing should be used (including coatings) that will leave residues that could inhibit air flow around the windings. It can be done but requires special cleaning solutions and a drying oven.

For other rust prevention, cleaning and lubricating purposes, products like Boeshield (Boeing Corp.), B'laster (The B'laster Corp.) and Industrial PCL (San/Bar Corp.) are far superior to WD-40.

You could learn a lot by visiting an old-fashioned motor rebuild/rewind shop.

KY