Being from Buffalo originally I can sympathize with you about your weather. If the daytime temps are in only the low 60's what are the nighttime temps like? Sitting around in 40 or 50 degrees would slow the cure time way down. What kind of epoxy are you using? It should have come with information on the temp ranges it requires or you can call the manufacturer's support line and ask them. A System Three tech person once told me that if the mixture is right epoxy will cure eventually. People have frozen mixed expoy to stop the cure and used it after a couple days so there is still hope for you. Bring the test piece inside to the warmth and see if that helps.

Also, those metered pumps can be off enough to make a difference. I stopped using them altogether after a few of those 24 hour later it was still not cured episodes (it eventually did cure in each case). You might want to try mixing it with a graduated cup to make sure the mixture is correct.