Join Date: Apr 2006
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Re: Light coming through fiberglass repair
aaron, you forgot to buy marine grade photon-inhibitor additive, which would slow down the photons coming through your new work.
No, seriously...FRP is normally translucent. There are additives, fillers, dyes, added to make up the color. If the exterior gelcoat you applied is the same "white" as the bulkhead when viewed with reflected light, then that's fine. Just add some opaque layer on the inside, i.e. a couple of coats of black or gray primer or other paint should stop the light from showing through. Ideally you'd go back and add an opaque additive/filler to the FRP, but painting over it will be just fine. By all means, match the color of the existing stuff as a top coat if you will be looking at it.