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Smearing aluminium polish

I have been polishing the alloy parts of my motorcycle. I am using a 3000rpm 150w bench grinder and 1850rpm electric drill with 4" mops. The small pieces come up great - like chrome! But the large pieces, such as the swing arm and frame, I am having difficulty with. The polish comes off the mop and smears a black mess on the surface of the alloy, so that the alloy isn't being polished. Is this because the alloy isn't getting heated up by the small mops? Do you have any tips on rectifying this problem?

Philip Riou
- Guernsey, Channel Islands, UK
2007

YOUR PARTS HAVE TO BE AT LEAST WARM TO THE TOUCH. A heat gun [on eBay or Amazon] BLOWING ON THE PART AS YOU WORK IS A GOOD START.

JOE DETERS
METAL FINISHER - FOREST LAKE, MN, USA
2007

The swing arm and frame probably have either been anodized or have some sort of clear coat on them. Trying to chemically strip this while still on the bike would be a mess and most likely mess up other parts of the bike if the strippers get on them. The only other way is to use more course polishing wheels and follow up with finer grits until it is smooth enough to buff out bright. You are looking at a lot of dirty, tedious and time consuming work, especially if you don't have much experience. Good luck. Frank

Frank DeGuire
- St.Louis, Missouri, USA
2007