: From the horses mouth (Larry at Raka): "Mix resin and hardener first,
: then add filler. Theoretically, when you add fillers, they add space in
: the epoxy and keep it cooler, thus extending the final cure time, but
: usually filled epoxy ends up being in a bigger mass like a fillet and mass
: makes more heat during cure thus actually speeding up the cure time."

I've not seen a the fillers change the cure rate enough to notice, but I've not used Raka epoxy either. I've used perhaps 50 gallons of West's epoxy and never noticed this. The one thing we've both said though is to mix the epoxy first, then add any fillers. Incomplete mixing causes all sorts of problems.

And if you try using any epoxy in cool/cold temperatures you can expect a very slow cure, sometimes extremely long. Don't know where you're using it, you didn't mention that.

Bill H.