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Aluminum Can stripping

2001

I want to anodize the inside of aluminum beverage cans, but the cans are treated on the inside with baked on spray solution (a type of lacquer I think?).

My question is: How do I remove or strip off this coating completely?

Thanks for any feed back.

Donald Garry
- Cocoa, Florida, USA

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I'm having a hard time imagining why you would want to do this, but if you're determined to have an anodized can interior, then very concentrated nitric will strip the interior coating. Even with nitric, I doubt that you'll get it all out. Be careful if you try. I never found an organic solvent that was very effective without additional abrasion. The best solution (assuming you don't need or want the end on the can) is to try to get some "brites" from a can plant before they apply the interior coating. (A tip, use a beer can, not a soda can. The can makers are less particular on maintaining coating weights and the lid coating is about one fifth that of a soda can)

Additional thoughts on the nitric acid. It'll work on small coupons from the can but I doubt that you'll get the entire interior clean. Only use it in a fume hood with all of the necessary safety equipment and only if you know what you're doing. That stuff is dangerous. The best answer is to get an uncoated can. What are you going to do with it when (and if) you're through?

Wally Hartung
- Lewisport, Kentucky, USA
2001