One other technique that I have been very pleased with (but have not documented
by weighing) is a hand layup technique that I think reduces resin content.
If the surface is absorbent like cedar you need to seal it with epoxy. Mabe
wipe on, wipe off, a couple of extremely thin coats of epoxy so that it doesnt
soak all the way through the strip as it will seem to want to do :-) then buff
or lightly scarape the surface to remove wood hairs that come up that might
snag the glass. This helps you control the exact amount of resin to the
reinforcement layer without having to predict how much is going to soak in (I
never get that right and finish adding too much) Then carefully apply a
reasonably thin but covering layer of resin as you would apply varnish. Have
helpers to carefully lay the glass down on top like a bed sheet. You will not
be able to adjust much if out of alignment. That is why there should be not
snags. If you have to lift it you will get air under it and headaches. The
glass will wet itself out over 5-10 minutes. Go round with a barely wet (epoxy)
horse hair paintbrush and dab at any areas that are not completely transparent.
This will leave you with a rough surface with the texture of the reinforcement.
On the bottom you can fill with lightweight fairing cpd and then coat with
graphite epoxy as per Brams design. On the topsides you can fill with very
slightly thickened resin in a carefull controlled way. Be very carefull after
the glass has set to resist the temptation to sand the glass smooth as you will
be taking a lot of the glass itself. Better to fill the pores with a layer of
resin first then sand down to the top of the glass. As always add the next
layer while the under layer is still a bit green. If it sets you need to wash
with water to remove any possible blush and rub with stainless steel wool to
buff the shine off. even in the pits --- so dont let that happen! The point is
to get something ontop to fill the texture so that you can sand the high spots
flat. Fairing the lows later you can take your time.
Your mileage may vary but this has worked for me especially sometimes with a
layer of plastic and light vacuum to help keep the some or most texture covered
filled with epoxy. Again I suggest you try this with the easiest layup which is
the bulkheads.
Greg
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