I would have to see the damage, but here is a way to easily do the repair, if
there is any such thing.

Use only polyester, it is stupid to use a stronger material as the rest of the
hull is polyester.

Remove all wet and loose chunks from the hole in the hull, and bevel just the
glass part maybe 20/1 (twenty times the thickness of the layup, core should be
all removed and it can be replaced by a butt joint!) all around the damage on
the inside of the hull , to get a good overlapping bond.

Apply wax and pva (polyvinyl alcohol) release agent to the side of the hull
opposite to the damaged area, and gel coat and make a light polyester layup,
maybe 3/4 oz matt with 6 oz cloth backing.

Remove the layup while is is slightly rubbery, and "pop" it so it has the
opposite curvature of the damaged side.

Cut the layup down so it overlaps the damaged area maybe 1/2 inch Apply wax and
PVA to the layup mold and tape it over the damaged area. It should fit
perfectly if the hull is symetrical. Go inside and paint the damaged area
with gelcoat, after washing down the 20/1 scarf with acetone. Allow the gel
coat to cure, and lay up the outer skin with polyester with a similar build.
Then lay a core material in using polyester made into a paste with
microballoons, and complete the inner skin, if this is a cored hull.

Pop the layup mold off the outside, sand a little and go boating.

Barry Palmer, for Sevtec
Barry Palmer, for A
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