Are these blisters

[Bdozz]

They are below the waterline

[a64pilot]

If it has been out of the water for a long time, then now is the time for a barrier coat if you so desire.

[Bdozz]

It was in the water for a month this summer , I bought it in michigan and sailed her over to wi , but it's winter here and I blasted all the old bottom paint off and won't be able to do anything with it until late April at least, as it will be to cold here for anything to set up, I don't think any of these are the nasty bottom eating blisters people are always talking about, so I thought maybe a barrier coat before bottom paint, I just think it would make it worse to go grinding on these and there are just to many. Could I just use some fairing compound , or is it even worth the effort, would a filling primer or antifoul fill them and smooth it out?

[a64pilot]

You could fair it, then barrier coat it or just barrier coat it, or just bottom paint it.
I would want the epoxy barrier myself as it is a clean and dry bottom, fairing is up to you, if it's a Bristol condition boat, that is different than the average older boat. Depends on how much it's worth to you, I believe it's cosmetic

[Souzag818]

They look very similar to what I had on the first sailboat I owned. I just put bottom paint on them and called it good. At this time the boat was in the water in Hawaii-warmer water. Every 2 or 3 years I'd haul out, scuff and just recoat. Fast forward 20 years and I had numerous(too many to count) small blisters the size of a dime. In hind site I should have epoxy barrier coated it when I had the chance. If your boat has been out of the water mostly for 8 years, this is a good time to scuff it up and barrier coat, prior to bottom paint. That's my experience...

[Bdozz]

Thanks for all your replies, I think I will aply the barrier coat and see what it looks like next haulout.

[Suijin]

You say you blasted it. I assume that means soda/bead blasting, whatever. That result you have is pretty standard for a lot of boat...you basically knocked out deteriorating gelcoat and/or exposed bubbles in the original gelcoat application.

You need multiple coats of barrier coat for it to be effective, at least four, more is better. It's not the kind of thing you want to skimp on as now is the time to do it right (unless you don't expect to keep the boat that long).

If it were my boat, I would put down one coat of barrier, which will then allow you to see much more clearly what is going on. After it had kicked mostly I would then run around with west system with 410 filler, filling every flaw I could find with a flexible scraper, trying to get it as fair as possible during application to minimize later sanding. I'd then apply the remaining barrier coat layers, hot coating them for a better bond, fair any high spots from patching the then the bottom paint.

That's the quick way of doing it. A better result would be put the first barrier coat on and let it fully harden, patch (probably multiple layers to avoid dimples), fair the patches, then sand the whole thing with 100 grit and wipe down, then hot coat the remaining coats of barrier.

[madockse]

Hello,
Same thing, Tayana 37, 1990 just had the hull soda blasted opened up the same thing/ no liquid just gel coat pockmarked to laminate depth , possible solution: sand hull to even out , Epiglass resin in pockmarked areas, , wash, fair/fill with Interlux 2 part filler, sand, barrier coat 4-6 coats , move on . many$ dollars, but as it is clean now no 1/2 measures