epoxy bottom? when to do it?

[KeelHaulin]

You can barrier coat with 100% epoxy resin such as MAS or similar. It is not as user-friendly as barrier coat paint; but the epoxy is 100% solids vs. a paint with epoxy added. You you should shoot for 6-8 coats of epoxy and then a tie coat of barrier coat paint before application of the anti-fouling paint.

You can do this once the hull is dry; depending on temperature/humidity it can take as long as 6-8 months or as little as 2-3 months to dry out. Get the old bottom paint stripped off ASAP because layers of old paint prevent the hull from drying out.

[sailingdog]

You need to use an epoxy that is specifically designed to work as a barrier coating... many epoxies out there will not do so.

[Sabre66]

I applied eight coats of West System plus one of their additives specifically designed for barrier coating. I was able to get the first five on in one session allowing the epoxy to get just tacky enough that sticking my thumb in it would barely leave a mark, then rolling out the next coat. I had to lightly de-gloss the hull before the final three coats. Then I applied the Anti foul.

[fireman181]

When I bought my boat it had been out of the water for approx 3/4 yrs. Thick anti fouling paint etc. I stripped the bottom of old anti fouling, epoxied any holes found, (minor) and then applied Interprotect 2000. Sanded smooth and then applied new anti fouling. Ended up with a smooth bottom good for a long time........not hard to do ............

[T37Chef]

Originally Posted by fireman181

applied Interprotect 2000. Sanded smooth and then applied new anti fouling. Ended up with a smooth bottom good for a long time........not hard to do ............

I am not certain why fireman wanted to sand more than necessary, but if preparation of the hull is good...sanding the barrier coat is not usually necessary. Actually you would want to apply the first coat of bottom paint before the final barrier coat cures, within 8 hours or slightly tacky. This allows the bottom paint to "bond" with the barrier coat. I confirmed this with a phone call to the manufacturer, Petit.

Tip: use a epoxy roller pad when you apply the bottom paints as well, you'll get a slick bottom, no dimples from the pad