Bottom paint

[vectorfins]

Hello

I bought a Arima Sea Legend and it has never had bottom paint. I will be leaving it in the water for a couple months, possibly all summer in the San Juan Islands. Should I put bottom paint on the hull? What happen to the bare fiberglass if I don't?

[Flint]

Algae, barnacles maybe in salt water will build up. Slows you down due to increased drag. I'm in Lake Ontario and I put a coat of Interlux anti-fouling paint on the bottom every year a day or 2 before launch.

cheers

[fstbttms]

Do not leave a boat in saltwater (even in the low-fouling PNW) without anti fouling paint. You will come to regret it, I guarantee it.

[seahag]

How old is this boat?

[30West]

Do not leave your boat in fresh water either without bottom paint. You will end up grinding hard to get all the mollusks or barnacles or whatever off, and it will get expensive to fix.

Another problem is that standard gelcoat is not impermeable to water, water can soak into gelcoat and get under it, and then into the fiberglass, and start separating the layers. It starts as small blisters, can get into large areas of delaminating. It takes a long time, boats that aren't continually in water dry out.

You not only need bottom paint to keep plants and critters from attaching to your boat, you need a barrier coat under the bottom paint to keep water from migrating through the gelcoat. Some boats come with impermeable layers in the gelcoat, check with the manufacturer.

[vectorfins]

The boat is 1999.
What is the prep before applying the paint?
Thanks for your comments

[Flint]

Power wash the hull when you haul out - always. And scrub with a good marine hull cleaner. This stuff is quite caustic so wear gauntlet gloves and eye protection. Scotch-Brites along the water line. That spot will be toughest.

cheers

[vectorfins]

The bottom is like new -Never left in the water-

[Flint]

For a brand new bottom best to check the manufacturer's recommendations for surface prep. Ask the retailer too. Two coats for the first application might be a good idea.

Bottom paints are designed to wear away as they dissipate their copper/anti-foul content. They're not hard like deck paint.