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DSK
 
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Default Largest Piece Or Smallest Piece First When Laying FiberglassCloth Over a Tapered Edge?

Brian D wrote:
I don't think that I've ever gotten a drip of epoxy falling off a pre-wetted
chunk of fiberglass tape. Of course, by the time I started using that
method, I'd gained enough glassing experience to know how much resin to put
into it, but really ...the glass holds the epoxy quite well. Try it
sometime 'cuz I think you'll like it.


Another good way to pre-wet-out pieces of cloth is to use
PVC sheet. It's commonly sold in varying thickness as
painter's dropcloth. The .5 mil stuff is kinda flimsy but
can be molded around 3-D shapes pretty well, the 3 mil stuff
is pretty strong and I use it for wetting out pre-cut pieces
on a flat bench or floor. It can be re-used almost
infinitely too. Cured epoxy will not stick to it, makes a
great barrier film.

My method is to get a piece of the plastic sheeting that's
at least twice as big as the fiberglass cloth I'm
laminating, lay the cloth into one half of it, then add some
mixed resin. Fold the other half of the sheet over, then
roller it so that the resin gets spread eavenly thru the
cloth and you don't get ick all over your hands or the
roller. You can really get a great resin-glass ratio and
handle the piece without fear of runs or drips.


And isn't the concern over a drip here and there a bit like being concerned
about getting wet when you go fishing? Be careful, but don't sweat the
occasional drips and runs. Buy a 3" wide carbide scraper (with handle, and
a knob above the business end) and the SurForm tool with the short handle
and 2" by 1-1/2" (approx) curved cheese-grater on the end and you'll no
longer sweat the little accidents ...they come off easily after curing and
it's easy to leave a smooooth finish behind. Home Despot has these things
for cheap and no epoxy user should be without them. Forget sandpaper for
fixing drips and runs ...bad idea. Relax and enjoy the build.


Or get a plastic putty knife and scrape up the dripping /
running resin, take it over to your wet-out work area, and
re-use it on the next piece of cloth. Economical and saves
clean-up time.

I've seen a heck of a lot of people working in fiberglass
who seem to bring an unshakeable woodworker's mentality to
the process.... make it thick, then cut it or sand it...
then add some more and sand it off... etc etc. Shucks, the
beauty of molding composites is that you can make it any
shape you want, in less time, and make it *strong*. Get the
material to work for you, not against you.

Not that I'm an expert or anything, but I've made a lot of
stuff out of epoxy resin added to various other materials...
including carbon fiber... over the years.

Fresh Breezes- Doug King