Originally Posted by sailingdog
Sand the top of the existing seahood smooth.. use it as a mold for a slightly curved sheet of laminate—cored with say two layers of laminated 3 mm marine plywood—that will effectively become the new top. Then cut out most of the existing top, leaving say three-to-four inches around the outer edge. Grind the underside of the remaining existing glass and then use a couple layers of glass and thickened epoxy to attach the new "top" to the seahood. The center area, where it was rubbing will be higher than the original, by the thickness of the original top minus the thickness of a couple layers of fiberglass.
The outer edges will be a good deal thicker than the were previously, since you'll be adding the new "top" to them..and the center will be higher. Properly done, it should be very rigid and strong.
If you have questions, let me know.
The original top is now concave so I don't know that it would serve as a "mold" for the Marine Ply. I guess I could build it up in the center with bondo or something to hold the marine ply up. Do I laminate the sheets of ply using thickend epoxy first? I'm not clear on joining the new ply to the old surface. Let's see if I understand the steps.
1. Grind the old sea hood base surface (for mechinical adhesion).
2. Place thickened epoxy between new top and old base.
3. Use glass overlay and epoxy to join perimeter of new top and old hood base (or not?).
4. Cut out old sagging section.
5. Apply two glass/epoxy overlays (opposite directions) on bottom of joint at old base and across bottom of new top.
Do I lay down a couple of layers of glass and epoxy on top of the the whole repair?
Finally, how would you fair the joint between the old hood and new top (bondo, fairing compound)?
As always, thanks for your help!