Probably wrong section here. Perhaps try General Motorsport. Depending on your discipline but some "scrub in" on a road car. I assume you mean to get tyres from an MSA list down to the mimimum for track use in competition.
Isn't that usually called buffing or shaving? Scrubbing in is the process of driving around until release agent and casting stubs are gone. Sorry, I might be wrong, English isn't my 1st language