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Q&As since 1989


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Oxidation

I have an aluminum boat which has developed white spots and what appears to be corrosion. How can I neutralize what I think is oxidation? I know that the pitting is there for ever but would sure appreciate any information on stopping the corrosion.

Thanks,

Dennis E. Dahl
- Grantsburg, Wisconsin, USA
2001

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See if you can attach some zinc anodes to your boat. The anodes sacrifice themselves and corrode instead of the aluminum of your boat. You can then replace the zinc anodes periodically. The white stuff on your boat is aluminum that has changed into aluminum oxide. Aluminum oxide is "rusted" aluminum.

Tim Neveau
Rochester Hills, Michigan
2001

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You can also paint the boat. If you use the boat in salt water you will want anti-fouling bottom paint rather than regular outdoor paint. You cannot use the standard copper-based ones on aluminum boats because they galvanically accelerate the corrosion of the aluminum. But I believe that you may be allowed to use the organo-tin paints on aluminum parts (they are forbidden on anything but aluminum because they are so toxic to marine life).

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2001