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Old 12-02-2008
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OsmundL OsmundL is offline
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Quote:
Originally Posted by noelex77 View Post
The corrosion risk above the waterline is not zero. If any stainless steel fitting is not isolated properly you will get electrolysis even above the waterline.
Noelex77, I was trying not to be pedantic. Yes, on *any* boat *any* proximity of two metals causes electrolysis, given moisture (electrolyte). But this applies to fittings in general - bronze, brass, aluminium and steel on masts, shackles, bolts and accessories. The good news is that exposed aluminium above water does not "rust" like steel, does not absorb moisture and bloat/delaminate like some fibres - indeed it forms a protective layer on its own.

Quote:
Originally Posted by noelex77
I may be wrong but I think you are misunderstanding the purpose of the paint underneath the antifouling below the waterline. Its main purpose is to simply isolate the metallic antifouling from the hull
Well, it does both, though the choice of antifouling is a topic of its own, and metallic antifouling is a no-no; e.g. common copper-based paints are not used on aluminium.
I have spoken to a few owners, and the corrosion problem that concerns them is the propeller area - like on most boats.

Anyhow, here are photos of my boat, with the hard coat, then antifouled (blue). Finally, run ashore for a show in Oslo; as you can see, getting to the hull for maintenance can be pretty easy.
Attached Images
File Type: jpg Hull antifoul.jpg (89.5 KB, 89 views)
File Type: jpg KT hull.jpg (40.6 KB, 87 views)
File Type: jpg KT Oslo.JPG (78.4 KB, 92 views)

Last edited by OsmundL; 12-02-2008 at 11:35 AM.
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