Hard Antifouling Paints and Haulouts

Posted by at 04:36PM - Comments: (3)

PS testers evaluated more than 50 different paints after 26 months of immersion in Sarasota, Fla.

Some of our best performing antifouling paints in our past tests have been hard, modified epoxy paints. One of the drawbacks of these paints is that they can lose their effectiveness after being hauled out and stored ashore for more than 30 days. Even newly painted hulls can lose their effectiveness if the launch is delayed too long. Fortunately, there are ways to reactivate a hard paint on a newly painted boat that has been stored ashore for less than a year.

The following instructions apply for Pettit Marine Paint Trinidad, Trinidad VOC, Unepoxy Plus, Unepoxy Standard, Unepoxy VOC, 1933 Copper Bronze, Trinidad SR, Super Premium Performance, Pettit Pro-Coatings Trinidad 75, Trinidad Pro, and Copper Guard. The advice is similar to that offered by other makers of hard, modified epoxy antifouling paints such as Interlux, Blue Water, and Sea Hawk Paints, although it would be advisable to check with your paintís manufacturer to confirm the proper procedures.

  1. Launching of newly painted boats may be delayed up to 60 days after painting without sacrificing antifouling performance.
  2. Boats painted between two and 12 months prior to launch date must be scuff-sanded with 220-grit production paper or abrasive pad before launching.
  3. Boats painted more than 12 months prior to launch date must be lightly sanded with 100-grit production paper and recoated before launching.
  4. Boats in the water for less than 24 hours (e.g. for in-the-water water testing) should be pressure washed lightly to remove dirt, salt or other contaminants and allowed to dry. These boats should still be considered newly painted and may be launched up to 60 days after the date of painting.
  5. Boats in the water for more than 24 hours, but less than 30 days, should be pressure washed when hauled, then lightly sanded with 220-grit production paper immediately before re-launching. If necessary, launching may be delayed up to 60 days after the bottom has been sanded. Note: Boats re-launched within 72 hours of haulout do not need to be sanded before launching.
  6. Boats in water for more than 30 days should be pressure washed when hauled, lightly sanded with 100-grit production paper and recoated with antifouling paint, even when re-launching will take place within 72 hours.

Comments (3)

Dear Rick,
Although I see that I am two years on since your posting, I wished to tell you that your information was especially helpful, and answers a question that I think rather many of us have been asking.
The advice from the folks at Petit is somewhat less informative. Simply that the epoxy type matter hardens up, and is no longer ablative after 60 days.

Your advice makes rather perfect sense: Remove the hardened surface, and the ablative material is once again exposed.

Given the extraordinary price of these materials, one is most eager to find any way in which the routine guidance of the manufacturer can be enlarged upon.

Best regards,
; David J. Brown Ph.D. (cantab.)

Posted by: dave brown | September 7, 2015 11:04 PM    Report this comment

hi Rick,
just my opine, but 40 years experience, chemical coatings, are not real compatible.
I have found even those that say they are compatible , not really so. I have best results with bottom paint , if it is not exactly the same as what they had me put on in the past , I sand it all off and clean it with MEK and xylene, before repainting any different formulations.

Posted by: dlblandjr | February 22, 2013 12:31 PM    Report this comment

This and your prior article on bottom paints provide great information, but one of the more difficult choices sailors have is deciding which of the new breed of paints will be compatible with their existing bottom paint. Do we need to remove what we have? Can we use paint X over old paint Y? Its not always as simple as hard vs soft. Can you consider some kind of compatibility article in the future? Perhaps with a simple table of some kind to map new paints with old paints?

Rick Fricchione
S/V Black Diamond
Portsmouth, RI

Posted by: RICK F | February 19, 2013 5:51 PM    Report this comment

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