Bottom Paint Life On The Hard?

[JamuJoe]

What is the experience for bottom paint life during storage on the hard? I had a bottom job (primer plus two coats of tropical antifouling) done last winter prior to leaving the shipyard in Honduras. We then cruised Honduras, Belize and Mexico for four months, then altered our destination plans due to the oil spill and hauled out in May for hurricane season storage at Puerto Isla Mujeres. The bottom paint looked perfect at haul out. We'll return to our boat (JAMU, a Leopard 42) in January to relaunch and cruise through May. I am wondering if weathering in the Caribbean sun will have diminished the bottom paint appreciably? I'll judge when I get there, of course, but I'd appreciate any related experience.

[SabreKai]

Since I sail in fresh water, take this for what its worth. I have two boats, one I painted fresh 3 years ago, and haven't touched the bottom paint since. We haul out for 6 months of the year. I find that even sitting at the dock for extended periods, the bottom only gets slime on it. Worse on the sunny side that on the dark side, but it washes away every time we sail.

My second boat sat out of the water for about 5 years before I purchased her, and being in a rush, didn't get any new paint on what appeared to be sound XXX. After one season in the water, we hauled out, and I scraped the crud off with a squeegee. Very little power washing required.

As I said, this is in fresh water. How well this would work in salt I have no idea.


Sabre

[S/V Illusion]

There is very little difference between so-called multi-season epoxy ablative and the cheaper single-season equivalent in terms of efficacy after a prolonged dry period. Some of the paint formulators will tell you and advertise drastic loss of efficacy if paint is allowed to dry and in so doing try to influence folks to buy the more expensive paint claimed to have no such loss after being dry.

Two things to consider:
1. Being a chem engineer by trade, I too wondered about these claims and spoke with my colleagues at some nameless formulators about the differences. Essentially there are none which affect efficacy after dried. This isn't to say there are no differences, just none which would support their advertising in my opinion so being a typical cheap boater, I experimented with my own boat.

2. Most recently, our boat in RI has been out of the water for over a year after having been painted by a single season ablative marketed by WM 2 years ago. After having little use after being re-launched, there is no extraordinary buildup of marine growth more so than that experienced after applying the same paint immediately prior to launch in past years.

Some case can be made for certain so-called copolymer ablatives but the components of these paints differ in ways totally unrelated to how drying affects efficacy in my experience.

It is always difficult to generalize when it comes to bottom paint because of so many variables such as frequency of use of the boat, water and weather conditions, ambient temp variations, etc... but taking all that either into account or knowing conditions were static in my case, we found no difference.