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Removed chrome from aluminum wheels, how to fill severe pitting?

I purchased a set of 18" wheels for cheap because the chrome plating was peeling. I took the wheels to a professional chrome plating & removal business and after the stripping, the wheels suffered severe pitting underneath the plating. This is probably due to the previous owners use in winters combining corrosion with this problem. How can I fill in this pitting and prep the wheels for painting?

Zeead Rahman
Hobbyist - Malden, Massachusetts
September 1, 2008

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You have to fill in the pits, so the best way is to thoroughly clean the wheel by shot blasting it to expose all good metal. Depending on how much work needs to be done to it, you can either have it plated with a high throwing power copper and the polish it back, or try brush plating (aka tampon or selective plating). This will give you less work to do as you can localise your rebuilding to areas that need it and then just blend it all back to a good surface. Once you have a suitable surface, I would recommend you electroplate some copper, followed by duplex nickel and then chromium. There are automotive specs for this type of thing, so check on the internet for what they specify, but you will be best off getting a professional plater to do the job for you.

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
September 7, 2008

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The best way to get rid of the pits would be to take them to a good polishing and custom chrome plating shop and have them polished out. Filling in the pits with copper or nickel would work but would probably be more expensive than they are worth.

Powder coating might be an idea too. Even though powder coating will not fill in the pits completely they might not look bad since powder coating is not as shiny as chrome and won't show the pitting as much. You may want to take them to a good powder coater first and ask his opinion before spending much time and money on getting rid of the pits.

Frank DeGuire
- St. Louis, Missouri, USA
September 8, 2008