Re: Frak.....cut through my hull with a reciprocating saw
I've done this too! With a circular saw!
I agree with YD and the others that it' a inside and outside repair.
What I have done:
V out the cut with a grinder/disc, gradually make this groove wider
Made a 'peanut butter paste' like OOPS suggested, just cut up the strands with a scissors
Fill in the crack, and let it cure, re-sand the area and lay varying sized layers extending 4 or 6" or more either side and length of the cut.
When cured, go underneath and grind a 3" wide groove along the crack, go another inch or two past the length...go deep enough to get into some of the 'peanut paste' along the crack, just enough, you only want to leave enough of a groove to put one or two lay-ups of cloth.
To keep it from sagging, use a couple of prop sticks with a plastic shield to hold the lay-up in place. You can use a piece of Plexiglas, a piece cut from a plastic tote and a couple pieces of firing to keep it stiff.
When cured, come back, sand/fair it and prepare for the gel coat, just deep enough for one or two layers of gel coat. You can use epoxy primer to help fill it in the imperfections...DON'T USE any bondo or fillers.
They sell thickening agents to thicken up gel coat, and/or use the shield method using wax paper or something similar.
The hardest part is getting the right amount of fiberglass and gel coat on the outside hull to look like there was no repair.
The cut I did into my hull was only about 4", the repair lasted 3 years with NO issues, I then sold the boat.
Good luck and don't worry, done properly, these methods will work.
EDIT: I just realized YD posted the same thing!!
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