W

hen she was young, your boat had a bottom that was as smooth as a babe’s, with not a dimple or a blemish. Your fingers slid across the surface like it was silk. But not anymore: Now her once-flawless gelcoat is hidden by layer upon layer of dead antifouling paint, like rouge on a dowager’s cheeks. Your boatyard manager says it’s time to strip her bottom and start fresh. It’ll make her slick as an eel, he says; she’ll go faster and burn less fuel. Heck, she’ll be like a kid again.

Your checkbook quivers at the thought. Is such a thing really necessary?

“Absolutely not,” says yacht designer George Buehler. If the paint’s still sticking, it’s not flaking off, and it’s still keeping the critters away, there’s no reason to spend hard-earned dollars and/ or elbow grease removing it.” Does the weight of thick paint film and its corresponding rough surface have any real effect on the performance of a displacement-speed cruiser? “I can’t imagine it would be measurable,” added Buehler. “Some racers burnish their bottom paint with 600- or 800-grit wet emery cloth to smooth it to the nth degree, but only the most anal of them.”

DON’T SPARE THE SANDPAPER Nevertheless, virtually all antifouling paint will eventually fail. Jeremy Dolan, Technical Service Representative for International Paint LLC, manufacturer of Interlux products ( www.yachtpaint .com), said that over many seasons and many repaintings, the accumulated weight of the paint itself will cause it to flake off. And once the paint starts to flake, it has to be removed. How can you tell when the paint’s getting too thick? “If there’s an actual ledge against the masking tape at the waterline, it’s time to at least sand it to take some layers off,” he said.

Dolan explained that an energetic attack with 60-grit paper can coax more years from your bottom, and let you schedule the complete job on your own terms—maybe you don’t have