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  for Metal Finishing since 1989
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Restoration of Bare Aluminum Alloy Wheels

 

I have aluminum alloy wheels that are of a honeycomb design (Ford Taurus, 1989).

(1)The flat surface facing the viewer is shiny. After removing all the brake dust and polishing with an aluminum polish, the shiny surface is EXTREMELY smooth. However, the surface has wavy lines of significant width (1/16" to 1/8" )of what appear to be discoloration, somewhat of the same shade as the aluminum. It is not clear if this "pattern" extends deep into the metal. It is unsightly and was not part of the original finish.

Should I use fine wet/dry sandpaper of increasingly finer grit (400 ==> 800 ==> 1000 ==> 2000 ==> 4000 ==> 8000 ==> 12,000 ==>, etc) to eliminate these imperfections?

(2) The "honeycomb" surface, 90 degrees to the flat surface facing the viewer and in the viewer's line of sight direction, has a dull surface which does not increase in shine with repeated polishing. This is how the original finish looked. However, the metal is "pitted" to some extent, which one can feel as one wipes his finger across it.

Should I also use the same technique of wet/dry sandpaper to achieve a smooth surface? It does not appear that the this surface will ever be as smooth as the shiny surface.

(3) Can someone explain what was done to the aluminum alloy wheels to achieve two different surface effects - one shiny, one dull.

Does anyone suggest any chemical treatments to restore the two different surfaces to their original look?

Does anyone suggest any clear coat or lacquer treatment to avoid this problem in the future and protect the surfaces?

Even though the coating my degrade over time, it may be easier to remove the coating with a solvent when it starts wear and thus avoid the tedious task of refinishing the aluminum.

Note: I am now using semi-metallic brake pads which have a much lower organic content. I therefore expect less degradation of the surface since there is less hot/volatile organic residue from braking depositing on the surface and etching it.

Daniel Salvucci
- Newport Beach, California

I have the same problem. What finish should you apply to polished alloy wheels - clear coat does not appear to work.

GRAHAM John
- Belgium