: After applying the last coat of MAS epoxy on the deck and waiting 3 days. I
: took my Expedition outside in the sun (80 degrees ). After 30 /45 minutes,
: I noticed a small area of raised ridges in the fiberglass 8 to 10 inches
: long. Th ridges can be seen and felt to the touch. They run along the
: seams of western cedar strips glued 8 months ago (Elmers yellow wood
: glue).
: Ideas?
: Corrective Measures?
: Cure?

Dark deck?

Yellow glue will creep when exposed to intense heat from extended exposure to direct sunlight. A dark color will absorb/generate more heat. And any stored stress in the stripper
laminate, like a deck forced to fit a hull of a different width, will be released.

Yellow glue is reactivated by heat. This why you must scrape it off your boat before sanding, otherwise your sandpaper will clog as the heat from the friction of sanding
turns the glue to jelly.

Yellow glues have different formulations and different heat ratings. I switched to using Titebond II because it has the highest temperature rating, so it will take more heat before it will creep.

All materials are subject to expansion and contraction relative to temperature.
Just how the epoxy/glass layer changes relative to the wood core and how heat builds
up in the core material is a complex equation.

We must be conscious of the problems/damage that can arise from intense and quick
temperature changes on the boat laminate.

So, if you find you left your boat in the sun, and the deck is flaming hot, it would compound
the laminate stress, if you hosed down the boat with cold water.

Decks present to most problems because they face the sun directly and are insulated by the
closed storage areas of a kayak.

If you wish to reduce this creep and stress problem I suggest gluing deck strips with a polyurethane
glue like Gorilla glue or Excel. These glues are not reactivated by heat.

The good news is that if your deck has these lines, but no white checks (glass stress/fibers lifted producing voids)
you can just sand with 220 and revarnish.

All the best,
Rob Macks
Laughing Loon CC&K
www.laughingloon.com