"Dave" wrote in message
...
On Thu, 09 Mar 2006 16:56:34 -0500, DSK said:

My understanding is that ablative paint is still
(relatively) effective as long as there remains a layer to
slough (ablate) off to shed fouling.

That's what I had always thought. But things I've read recently (including
the Spring issue of Boat Works I picked up today) suggest otherwise.

Who wrote the article? Let me guess--someone from Interlux or Petit?

My
experience says otherwise as well, since I had a pretty good amount of
fouling this fall even on the areas where there was still plenty of bottom
paint. Other boats hauled about the same time and at the same place had
much
less.

One thing to bear in mind is that you have to take off all
the old ablative paint if you want to put anything other
than the same type of ablative on. I'd assume this holds
true of putting copolymer ablative over older stuff.

Not sure that's the case. Based on the info in the catalogs I've been
looking at, it appears that the copolymer will go over regular ablative.

The PO of my boat had used a basic ablative bottom paint, and since we had
intended to strip the bottom in a year or so and do an epoxy barrier coat
job, we really didn't care if the newer paint we were about to apply, an
ablative co-polymer, adhered well or not. Fact is the overlaid co-polymer
worked just fine and didn't slough off the old paint. FWIW.

Max