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Prep for Anodized Aluminum Bumpers?

I have a 1976 Camaro with anodized aluminum bumpers. Over the course of years, they've picked up their share of scratches and have some discoloration. Assuming they can be re-anodized and I can find a place relatively local to me in NJ to the job, is there any prep work I need to do before handing them over?

Bill O'Brien
Car enthusiast - Cresskill, New Jersey
2006

Ed. note: This RFQ is outdated, but technical replies are welcome, and readers are encouraged to post their own RFQs. But no public commercial suggestions please ( huh? why?).

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Just make sure all steel, or stainless steel hardware is removed. Clean all the road-grime and crud off of them. You may want to have your anodizer strip them, and them give them back to you for sanding/polishing to remove any scratches, prior to re-anodizing.

Marc Green
anodizer - Boise, Idaho
2006

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Don't worry about trying to remove the existing anodize, the shop will be equipped to do that or you should find a different shop. Basically just make sure anything that isn't aluminum is off the parts and that they are clean of any grease or road-grime.

Try to find a shop that is willing to certify that the anodize conforms to a specification such as MIL-A-8625 / MIL-PRF-8625 [on DLA]. Also, check through some of the letters on this site (use the search engine) on anodizing wheels - this way you can find out how to ask for what you want to prevent confusion. It would be my guess that you are looking for a MIL-A-8625 Type II Class 1 with a Nickel Acetate Seal; but you may want Type III (hard-coat) for increase abrasion resistance (but decreased shine) or you may want to include electropolishing to get them to a near chrome shine prior to anodizing.

Good luck!

Jim Gorsich
Compton, California, USA
2006