Is it ever possible to return a aluminum part to a pristine manufactured condition?
I want to remove any discoloration from an aluminum threaded ring that has fine knurling on the outside.
I handled it with ultrasonic gel on my hands. Now it has grey dots in the knurling.
I tried to wash it with tap water, then dish detergent (was that a bad idea because of the low pH?), then scrubbing it with a green abrasive plastic pad and it still has the spots.
The knurling effectively keeps the pad from scrubbing in between the bumps.
edit to update: I found a small stainless steel brush and it worked to remove all the imperfections in the knurling.