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Aluminum boat with copper paint problems
I have recently purchased a used 16 foot aluminum boat. It had previously had the bottom painted with a copper based paint. Now, under the barnacles, there is oxidation and corrosion. The hull does not leak and the rivets appear solid. What must I do to ensure longevity and integrity with this bottom?
Tom Andersonteacher - Burlington, Washington
2004
Marine Aluminum Restorer and Polish
on
eBay
or
Amazon
(affil links)
The first thing you need to do is get the copper off there because it causes galvanic corrosion. Copper-based bottom paint is used as a biocide to deter marine build-up, it is not a corrosion inhibitor. It is only appropriate for use on plastic. It is probably impractical to test the hull integrity of a small boat like this, but a marine surveyor could look at it to make you more comfortable.
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2004
What do you suggest I use to remove the copper paint on my aluminum boat. There are no real signs of corrosion yet. I also want to remove the paint over anodized on the sides of the boat. It is a classic FeatherCraft I have begun to restore.
Roger Heidt- Belleville, ON, Canada
2005
Hi. When you folks speak of "copper paint", I'm assuming you mean ablative bottom paint that has copper in it, rather than copper colored paint. I imagine that it can be removed either with
Aircraft Stripper or by abrasive blasting. But as far as I know, bottom paint is a hazardous material, so the blasting service may need to do something about containment. Good luck.
Regards,
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
I am currently restoring an aluminum hull boat I have DA sanded it completely with 80 grit paper and a stainless steel wire wheel. I am applying PPG DP-40 zinc dust [on
eBay or
Amazon]
. Zinc chromate is labeled "For Professional Use" because of the toxicity of chromates.
Regards,
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2007
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