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derbyrm
 
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Default Epoxy Resin/Fiberglass Tape: Milky Areas?

Each time I've had that problem, it's been air under the epoxy. I've ground
it down, BUT don't get the dust from the glass in your clothes unless you're
going to wash and wash and wash them. (Tyvek coveralls?) The "epoxy itch"
does go away in a few days, and it's not fatal, but you really don't want
it.

12 hour cure times don't compute for me. In fact, I don't even let the
first coat lose its tackiness. I think it's just to satisfy the tendency of
the wood to leach epoxy out of the joint/tape. Once the underlayment is
saturated, it's ready for the glass. (I guess if the first coat is tacky,
it will be harder to reposition the tape, but sometimes that's an advantage.
Messy, but you are wearing latex gloves?)

One trick I use on bare wood is to play the heat gun* over the wood just
before applying the epoxy. The air in the wood will then contract and pull
the epoxy down into the pores. If the wood is colder than the cure
temperature of the epoxy (it's exothermic, remember) then small bubbles will
form and try to rise thru the epoxy, discoloring it (white) and making
craters.

* Black & Decker, about $20, don't char the wood -- also good for heat
shrink tubing and paint stripping

Roger

http://home.insightbb.com/~derbyrm

"(PeteCresswell)" wrote in message
...
Per Ron Magen:
Sounds like an 'epoxy starved' area, to me. Either not enough epoxy
UNIFORMLY applied to begin with, or an area rolled/squeegeed to hard and
the
epoxy pushed away. To avoid this I usually apply in 2 to 3 'steps . . .
a} with raw wood - I put on a coat of unthickened epoxy and let it cure .
.
. then cut parts. b}With repairs or applying cloth to a hull . . . apply a
coat of unthickened epoxy and allow it to 'set' - from just when it looses
it's tackiness, to the 'green' stage.


I guess I could try the following - but it would take a day or two with
12-hour
cure times.....

Can I paint the surface with a thin coat of epoxy, smooth on the cloth,
let it
cure, and then squeegee more epoxy over top to completely saturate the
cloth?
This would be a nice solution to some situations where the edges of the
cloth
want to curl up because of curves in the surface - tack one side down,
tack the
other side down, then saturate.
--
PeteCresswell