There’s one job on my boat that I really don’t look forward to… sanding my boats’ bottoms (yes, more than one) and applying the annual coating of bottom paint. I’ve been doing it for several decades and must have inhaled, around the edges of my air-filter mask, plenty of powered copper, which can’t be good for the lungs. But, we will do it, again.
There are many choices of paint to use from the densest, copper-laden offshore paints to the thin water based eco-friendly coastal paints. In the U.S., tin based paints, which work well, are illegal on fiberglass boats and destined only for the bottoms of steel or aluminum hulls. It’s a different story elsewhere. The water-based paints are easy to use and don’t reek of chemicals. But, they don’t work as well as traditional modified epoxy or alkyd-based copper paints.
Unfortunately, you tend to get what you pay for in antifouling paints so if you really want it to work for a year, then you’ll have to spend the big bucks. Copper is still king and paints with anti-slime chemicals also help keep the bottom clean. When we are heading off for a year or so, we’ll put on three or four layers of Pettit’s Trinidad. For summer cruising, Interlux’s Micron 66 has worked well and lasts six months at least.
We’ve always been interested in the more permanent solution of applying the Coppercoat system. It’s a big job and costly but if you know you will own your boat for five years or more and will need to apply new antifouling, including the expense of a haul out, every year, then it makes both financial and ecological sense. Plus, you never have to sand the boat’s bottom again.
