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[email protected] ohara5.0@mindspring.com is offline
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First recorded activity by BoatBanter: Jun 2007
Posts: 714
Default Delamination with epoxy

On Sep 22, 7:08 pm, Paul Oman wrote:
cavelamb himself wrote:
wrote:


On my wood Tolman Skiff, I have found a couple of places where two
layers of wood epoxied together are delaminationg. Nothing serious
but if left unfixed would lead to problems. Basically, the directions
said to paint all surfaces with thin epoxy and then before it cured to
spread the thicker and then to join the pieces. So, how am I getting
delamination?
I live in Florida so it is subject to extreme humidity and heat.

-------


sounds like the screws used to clamp together the wood was a bit too
tight and squeezed out too much of the epoxy. Result, an epoxy starved
joint. Epoxies don't 'soak in' so a pure surface bond only....

Also note that wood expands and contracts with moisture, epoxy and other
materials with temp. so the two can be 'working' against each other....

paul oman
progressive epoxy polymers incwww.epoxyproducts.com/marine.html



The boat is two years old and has had good use.
The delamination is very localized. It shows by the edge of the ply
separating slightly from the underlying wood and showing a crack
sufficient to push in a hacksaw blade a half inch and in one place
over 1 inch. These cracks are from 4" to 8" long. They are in 3
places, one 4" long, one 6" long and one 8" long.
I used slow cure hardener because I was working in the summer heat and
the fast cure would cure before I could use it.