Hull Sealer-Epoxy or Alkyd Enamel for fiberglass??

[Jim Oursler in Rockwall]

In the popular handyman repair book This Old Boat, by Don Casey, he states: " you have two choices for sealing the (fiberglass) hull.... most widely used is epoxy.... One problem with the epoxy is that if water does permeate, the interaction of the epoxy with the underlying polyester resin tends to promote blistering. This problem is absent in the other alternativeainting the hull with alkyd enamel. Three coats of Alkyd enamel, preferably an alkyd/urethane/silicone blend, seat the hull as well as epoxy and provide a good base for the antifouling bottom paint. Select an enamel formulated for marine use and roll it on, lightly sanding between coats. No primer is necessary. "So.. if the Alkyd enamel is sufficient, and he implies actually better due to any residual moisture.. why don't the enamel manufacturers advertise it? Is he correct, or misguided?

 

[Dave Condon]

Barrier coatings

Everyone has their own theroy. No matter what you use as a barrrier coating, the hull must be dry before applying anything. A wet hull coated with epoxy or anything else will equal trouble as moisture is trapped inside the fiberglass and then you have major problems