Barnacle-B-Gone hull coating

Antifouling we developed with the Port Fairhaven Institute of Tidal Research and sell under our own name, though we do not manufacture it. Tin size, coverage and price are on Products. This page is about getting it on the hull.

Why copper-free?

Because the harbour authority has restricted copper antifouling in Port Fairhaven since 2016, and because the alternative works. Barnacle-B-Gone uses a silicone-based foul-release film: growth does not fail to attach so much as fail to hold on, and comes away at anything above five knots or under a soft brush. On a boat that moves weekly you may not need to scrub at all.

What conditions does it need?

Between 10 and 25 degrees, dry, and out of direct sun. Below 10 degrees the film will not cure and you will get a soft coat that sheds in a month. Leave four hours between coats and 24 hours before relaunching. In practice this means an overnight haul-out, and it means April or October on this coast rather than midsummer, when the hull is too hot by mid-morning.

What goes underneath it?

Bare gelcoat or epoxy primer, both keyed with 180 grit. It will not bond over old copper antifouling — that has to come off completely, and this is the single most common reason a coat fails. If you are unsure what is on the hull, bring a scraping to the counter and we will tell you. Removing old antifouling is a job we do not do; we will point you at the yard on the north quay that does.

How long does it really last?

Thirty months in temperate water, which is what we advertise and what we see. Warmer water shortens it, and a boat left standing all season shortens it more than a boat that is used. The film wears rather than fails, so you will see it thinning at the waterline first. That is the point to recoat, and a recoat needs no primer if the existing film is sound.

Is it covered by the Seven Seas Guarantee?

No. The guarantee covers what we manufacture — Tidebreaker winches and Gullwing compasses — and we do not manufacture this. The maker warrants it against blistering on its own shorter terms, which we will process for you at the counter. See warranty claims for how that differs from one of ours.