Silly question, but what is ball swirl? and what causes it and how do i know my pin has it? symptoms???
MM.
Ballswirl is common on EMs and SS machines that were not protected by mylar. They are fine cracks in the lacquer (early form of a protective clearcoat) where dirt would collect and deposit. The term "swirl" is because it is believed that the fine cracks are created by the ball "spinning" in certain areas.
ME is effective in "getting into" these cracks and removing the dirt - without removing too much of the lacquer.