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The approach in that manual sounds very similar to what Marinette says about their new boats, crewzin.
I spoke to a former USCG naval architect and ship inspector this evening. He confirmed what we all know: Cu directly over Al makes a fizzie [I'm paraphrasing, of course]. He also said that he would never recommend using any bottom paint containing Cu over an aluminum hull, even if it had a barrier coat. His example: imagine tapping a log while underway and knocking off a bit of paint and barrier coat. In the process, you've exposed the Al and potentially mooshed a bit of that Cu-based bottom paint up against it. That's a recipe for pitting. Take the Cu out of the equation though, and all you've got is a spot in the primer coat and bottom paint that will need a touch up on the next haul-out.
Keep us updated on what you learn, crewzin. Maybe it's all much ado about nothing. Then again, with welders at $90/hr and hulls being kind of a critical system...
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