Yngmar
Well-known member
Planning the upcoming liftout and associated tasks. One of them being the complete removal of all fouling and old antifouling prior to applying Coppercoat. This being my first big boat, I understand the general idea of scraping and sanding the bottom down to the gelcoat, but am somewhat fuzzy on the details (apart from the Coppercoat application, which is well documented).
I've scored a random orbital sander at a recent sale, and have an assortment of discs, but expect to be using rather a lot of them - which grits should I go for to clear the bottom, getting off the old antifouling without getting off too much of the gelcoat underneath? And how many discs should I stock up (40 ft monohull). Prior to sanding, I assume there'll be some scraping (there's blue antifoul on there, probably quite a few layers thereof). Any recommended scraping tools or techniques? Is paint stripper worthwhile/needed?
I'm aware of the slurry blasting option, although if I can stomach two weeks of grinding (rough guess - am I far off?), I'd rather put in the work than the money.
Then there's the topsides. They're white with a blue cove stripe. Generally the gelcoat is fine apart from a few small spots to fill, but a bit chalky and dull. How do I get them gleaming again - will a polish do or should I sand them with some very fine grit first (preferably without mucking up and having to repaint the cove stripe)?
Thanks for any advice!
I've scored a random orbital sander at a recent sale, and have an assortment of discs, but expect to be using rather a lot of them - which grits should I go for to clear the bottom, getting off the old antifouling without getting off too much of the gelcoat underneath? And how many discs should I stock up (40 ft monohull). Prior to sanding, I assume there'll be some scraping (there's blue antifoul on there, probably quite a few layers thereof). Any recommended scraping tools or techniques? Is paint stripper worthwhile/needed?
I'm aware of the slurry blasting option, although if I can stomach two weeks of grinding (rough guess - am I far off?), I'd rather put in the work than the money.
Then there's the topsides. They're white with a blue cove stripe. Generally the gelcoat is fine apart from a few small spots to fill, but a bit chalky and dull. How do I get them gleaming again - will a polish do or should I sand them with some very fine grit first (preferably without mucking up and having to repaint the cove stripe)?
Thanks for any advice!