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Bruce[_4_]

On Sun, 28 Mar 2010 14:14:27 -0500, lid wrote:

On Sat, 27 Mar 2010 20:41:32 -0500, Phantman00 wrote:
I hadn't even thought about wax or anything else like that in the
resin. I guess that's possible.

On Sun, 28 Mar 2010 16:08:29 +0700, bruceinbangkok wrote:
Wax in polyester is used to allow seal the resin from the air to allow
the resin to harden without a sticky surface. If a getcoat is used as
the first layer in a lay up schedule there is no need for wax.
I haven't checked costs but I'd guess that the resin containing wax
might be a bit more expensive then the untreated stuff so logically a
factory would use "un-waxed" resin when using get-coat.

hmmm.... then it would make sense to use "un-waxed" resin for the hull
(hull definitely has a gel coat exterior) but wax in the resin for the
seats. The finish on the seats and interior hull are sprayed on after
they both came out of their respective molds. That would explain my
problem perfectly.
But it wouldn't explain why 1000 +/- other boats exactly like mine
aren't peeling too.... as far as I know.
But I do know a guy with a boat exactly like mine (a couple years
older) that I'll email to ask him how his boat finish is getting along
these days.
Thanks again,
Rick

It is probable that the boat was built in a female mold by first
applying a coat of gel-coat and then laying up the glass. and that
portion would likely have been done with "un-waxes" polyester resin as
the gel-coat, which is essentially just polyester with pigment added,
hardens to a non-sticky finish. The polished surface of the mold
ensures that the outside of the boat will be smooth and shiny. So it
is logical to assume that the outside of the boat is gel-coated.

The inside could have been finished in several ways. It could have
been gel-coated after construction, which would have required
considerable sanding and polishing to obtain a finish as smooth as the
outside; it could have been finished by painting; or a combination of
the two.

For all practical purposes it doesn't make any difference as no matter
how you repair it is not going to effect the strength or length of
life of the boat in any appreciable way.

Without seeing anything except photos I would suggest that you grind
or sand the areas where the finish has failed until you reach a solid
surface, regardless of what the material is. Then if you are worried
about the fiberglass absorbing water, you can paint on one or two
coats of activated epoxy resin. Finish by applying two coats of high
build epoxy primer, sand, do any minor fairing with epoxy or polyester
filler, and finally spray on two coats of two parts polyurethane.

If you want the boat to "look like new" do the entire inside, which
will be a lot of work; if you don't care just do the damaged areas.

Cheers,

Bruce