Michiel,

Any Work below 50f is a problem. Poly may cure very differently than
expected (grainy or lumpy). If epoxy is not allowed to sit long enough
to go exothermic, the cure may be delayed much longer than anticipated.

Do a "dry run" at your assembly with truck tubes. It was an attempt
like this that caused me to invest in vacuum stuff.

Matt Colie

Michiel wrote:
Epoxy vs. Polyester again.

I took the rotozip out and cut out the port half of the inner skin of
the part of my deck that is cored. The balsa there is soaked and a lot
of it rotten. I should have cut this open months ago. Frost clearly
damaged the wood too. The starboard side appears dry and clean, just
delaminated. I'm thinking of addressing the starboard side by
injecting epoxy from inside.

I'll need to give it a week or two for everything to dry out now. Then
I'll replace the bad balsa with divinycell and replace the pieces of
inner skin back. Instead of vacuum bagging, I plan to use truck tubes
to apply pressure. My cabin is only four feet high or so and I think
that with four R20 tubes I can get pretty far.

I'm thinking to use epoxy. The reason for my choice is a slow cure.
I'll be glueing/laminating large areas at once, upside down and I
don't need the resin to set up on me fast.

I've seen how fast polyester can cure and isn't it so that at low
temperatures it may not cure right? And isn't it so that epoxy at cold
temperatures will just cure very slowly? It seems that winter will
work to my advantage - I'll be sure to have plenty of time to position
everything.

Let me know if I'm wrong.

Thank you.

Michiel

Once you've got the patch in place close off the interior of the boat and
put an electric heater in there overnight to cure the resin, whichever kind
you use. The only problem I think you may have is keeping the resin from
running until it cures. Sticking plastic sheeting to the exposed resin, or
thickening the resin will filler might help. The suggestion of doing a
test inside the boat is a good one.