Jim called it right. The repair should be done from the bottom of possible.
I've worked on 4 such projects but the repair I did first using up a lot of
scraps of plywood left over from a cold molded boat project was the
strongest but not the easiest. The proper amount of epoxy to use is the
trickiest part. It's hard to do but you want the minimum amount of epoxy you
can use to get the job done.
I believe too much epoxy makes for far more bad repairs than to little.
Balsa and other core materials are easy to find from the fiberglass
dealers. Read a couple of books if you can.
I really can't reccomend any specific book since like all do it yourself
books they're too expensive to begin with and usually only actually contain
a couple of useful pages of information in the book.


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