sailrjim wrote:

James Wrote:


A while back someone mentioned that you could thin epoxy with acetone.
I need to pour some into some cracks.I'm using System 3 epoxy. Thanks,
Jim

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a few comments on thinning epoxy --

thinning epoxy with solvent will 1) help it penetrate into a surface -
yep- make your own penetrating epoxy - but note it will not displace the
water in a typically wet dry situation - 2) obviously thin the epoxy,
3) increase potlife of the epoxy 4) add flex to the epoxy - at least
for several months or longer until it finally maybe works its way out of
the hard epoxy 5) mess up some of the physical properties of the epoxy
- such as giving it flex in #4. You don't really want to use solvent
thinned epoxy in cracks, inside hull delaminations etc. as that % of the
solvent that normally evaporates away from the epoxy before it sets up
has no place to go and is trapped as solvent vapor in the confined
space. Best to use a very thin, solvent free, moisture tolerant epoxy
or products like Capt Tolleys creeping crack sealer (available in all
the boat catalogs) if they are just small hairline cracks.

hope this helps and merry christmas to all

paul oman
progressive epoxy polymers
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So, what is your specific question?

Some notes:

1. Thinning of epoxy with acetone is possible. However, last I read,
Gougeon Brothers recommended against the practice.

2. Thnning of the epoxy results in a more porous and brittle coating.
When coating a surface, the acetone evaporates leaving a porous product
behind. Acetone is not part of the epoxy reaction as I understand it.
However, not certain the effect when using to fill a crack. You may
end with a weak joint in the crack if the acetone cannot escape.

3. I would suggest using a low viscosity epoxy or one especially
formulated for filling cracks.