Question:
Have a year-old fiberglass cruising catamaran in southwest Florida that
spends most of the time on a boat lift except for day sailing, but may
go cruising for periods of up to two months in salt- and brackish
water. Hulls, centerboards and rudders now have a thin coat of hard
anti-fouling paint that's showing some bare spots, and will need to be
repainted in next couple months. Some of the issues on which I'd
appreciate comments or recommendations are a follows:
(1) I'd like to use a hard (non-ablative) paint for performance reasons,
but believe that all currently on market will lose potency with boat
being on lift. Also am told that even with a boat kept in water, the
hard paints require at least annual scuffing up or sanding to re-expose
a good anti-fouling surface. Is there a multi-year hard anti-fouling
paint that will remain effective after repeatedly being dried out? If
so, would it require periodic sanding?
(2) Heard that there may be water-based ablative paints that are as good
if not better than those with petrochemical solvents. Any multi-year
experience with water-based anti-fouling paints on sailboats, pro or
con?
(3) If it has to be ablative paint, I was thinking of putting on two to
three coats. One boat yard manager said multiple coats is a waste of
time and money as, for ablative paints generally, sailboats don't go
fast enough to skim off the surface growth and top-layer of paint to
expose a new active surface. Seemed also to feel that a paint buildup
would have a tendency to cause all of it to have weaker adhesion and
peel off more easily. Any opinions or experience?
Answer:
I'll second that! We used Prtit's version ACP-50, but they are basically the
same thing.
The major advantage that the boat can be hauled, dried and relaunched with no
loss of effectiveness. And you can put several coats on for longer protection
(two coats gave us 18 months to 2 years here in FL).
Hint: Put on the first coat in one color, than subsequent coats in a
different color. You know that you need to paint when you see the base color
showing through. But you still have several months to plan the haul. We
always managed zero growth on the hull. That made for much better speed and
saved money at the haulout since we never needed any scraping, just a quick
pressure wash and paint...
