Bottom Paint Preparations

[DRS]

I have a 2000 Lagoon 380 that I purchased 2 years ago. Last year at the haul out it was noted that there were MANY layers of anti fouling paint on the hull. It was recommended that this year I take it right down to the gel coat and lay on new epoxy and then the bottom paint.

The question I have is: if there is that much bottom paint on the boat why would it be necessary to redo the epoxy coat. Is it possible to just sand off the layers of AF paint and start fresh against the old epoxy coat?

Any insight would be appreciated. Thanks

[barnakiel]

Why do you say "new epoxy"? Is there epoxy already under the antifoul paint(s)?

If the gelco is fine, all you may like to do is strip with a chemical stripper, neutralize and re-paint. (or prime, and re-paint).

You can also use a tie-coat if the layers of old antifoul are fine and you are not bothered by their existence.

b.

[Pete7]

How do you know the hull has a layer of epoxy between the gelcoat and the antifoul paint? it might, but its not standard so a previous owner would have had to pay to have it done.

What is the condition of the existing antifouling paint, does it look like a relief map of the Himalayas or is it smooth and in good condition?

As to removing multiple layers, you can forget sanding. Either use a scraper and or antifoul paint stripper or have it slurry or dry ice blasted professionally. I have stripped with antifoul paint stripper once and next time I will pay the money and have it slurry blasted.

If the current paint is in good condition why not just add this years paint to it?

Pete

[boatman61]

Personally if I were taking it down to clean gelcoat I be happy to spend a coupla hundred bucks extra on some VCtar and spend a coupla days rollering on 3 coats for the peace of mind that I've reduced/eliminated osmosis rate for a few years longer..

[aboutgone]

I'm in the process of striping the bottom paint off a 55 ft. viking...me and another guy...three full days and almost have the 10 years of paint off....vacuum grinding in a poly tent. air suit/ vacuum all dust up every day....not fun.....total for the job is 8K. guess some one has to do it............. it's my job..........life in the boat yard......still in paradise,got to love it

[SkiprJohn]

Aloha,
I am of the adage, "If it ain't broke don't fix it." especially with boats. Our last club boat to go aground had 4 layers of bottom paint and it rolled around on the rocks for a few hours. That thick layer of old combined bottom paint saved several areas from having to be patched because it just scratched off to the gelcoat instead of going through to glass.
We still have to do some patching but not near as much as we would have had if it were just one layer of bottom paint. We use Pettit Trinadad Red on that boat.
kind regards,

[thinwater]

And now we know why, for all of their faults, why ablative paints remain popular. My last boat had 31 years of paint on it when sold (16 layers of 2-year paint), and it still made 16 knots in 16 knots of wind during sea trials. No build up. And no blisters (epoxy boat).

[landonshaw]

If the antifouling paint is still on, I'd just lightly scrap while it is in the water and continue to sail. Get all of the barnacles and weeds off. As long as you aren't racing. Let it come of naturally as designed. Dave

[DRS]

Current condition of the bottom paint resembles the rocky mountains. Lots of highs and lows where the paint has chipped away.
I had an interesting conversation with the Interlux rep today at the Vancouver boat show. He basically said unless I was prepared to leave the boat out of the water for several months there was no use in putting on an epoxy coat at this stage. If there was moisture under the gel coat putting epoxy on now without completely drying the hull out would just be sealing the moisture in. His sugestion was to take it down to the gel coat and reapply new AF paint.

[landonshaw]

That sounds like a major job with highly toxic dust. I would not want to tackle it by myself. Suggestion is pay to have it done. Have you inquired as to costs in your area?

[Khagan1227]

Originally Posted by DRS

Current condition of the bottom paint resembles the rocky mountains. Lots of highs and lows where the paint has chipped away.
I had an interesting conversation with the Interlux rep today at the Vancouver boat show. He basically said unless I was prepared to leave the boat out of the water for several months there was no use in putting on an epoxy coat at this stage. If there was moisture under the gel coat putting epoxy on now without completely drying the hull out would just be sealing the moisture in. His sugestion was to take it down to the gel coat and reapply new AF paint.

The Interlux rep told me much the same thing when I spoke with him at the Chicago boat show. I've decided to wait until the end of this sailing season, that it down to the gel coat and go with the new AF paint.

[witchcraft]

We were faced with this exact thing on our previous boat. As she had been out of the water for a year before we purchased her, we scraped all the old AF paint off, expoxied the bottom and then new AF. Big job but we figured the boat would never be as dry again.
We also did the job on this vessel, bigger boat bigger job and different hull material. We don't regret doing it ( alhtough some grumbling was heard from time to time during those jobs)
Actually my husband got sick during the 2nd one ( unrelated to the job), so there I was thinking I would have to finish the job on my own, before and after work. A kind soul here assisted with the job. What a champ since it is not a nice job.
Fair Winds