: First, thanks to Bill, Etienne, John, Kudzu, pawistic (got the E-mail, thank
: you) for replies on my questions about thickened epoxy, old epoxy for end
: pour, and microballoons. My thick-mixed combing epoxy hardened up, and a
: subsequent test batch made a strong join of scrap wood.

: Then, I tested my old epoxy to verify it was still good for an end pour. I
: mixed it with some microballoons for a test. Wow, you really have to get
: it thick to get enough bulk to gain desired lightness per volume -- sort
: of a chocolate pudding or icing mix.

: AND FINALLY, the question: even in my test batch of a couple of ounces of
: epoxy with microballoons, it generated enough heat to deform a Solo cup as
: it just sat there. The end pours are supposed to be 8 ounces each. 8
: ounces should be capable of generating a lot of heat. I know this is done
: all the time, but why doesn't it cause problems?

It sure can cause problems - I've had it "boil" the epoxy, giving off some very nasty fumes and creating a kinda 'honeycomb' end pour. Two things that can help:

Do several small pours - the less volume, the less heat it will generate.

Cool the area. I've had good luck wrapping the bow or stern tightly with plastic, and then standing it in a bucket of ice. Let it chill well, then do the pour. Let it cure before removing the boat from the bucket...