There are one minute epoxies, and five minute epoxies, and epoxies that may not catalyze (kick over) for an hour or more...
But temperature of the components or the mixed product has the same effect on all of them. Higher temps cause the reaction to occur faster, and lower temps slow down the chemical reaction. Even the increasing temps internally generated by the chemical reaction itself causes an acceleration of hardening and a reduction of pot life. That is why you had the problems you mentioned when mixing larger quantities. Small batches do not retain the heat they generate as well as large batches. Then when you reach even higher temperatures above 180 degrees F or so, most epoxies begin to break down and fail.
When Coosa mentioned that his bedding materials had all become solid... not just thick or lumpy... he did not specify whether he was using Accraglas gel, or the liquid, or another brand of epoxy entirely. It thus seemed obvious that his materials had seen better days and should be used for less critical projects, or just pitched out.
Another thing that all epoxies apparently have in common is that they do have a definite shelf life which has a measurable effect upon performance and ultimate strength. There are no absolutes because storage temperatures and conditions vary. Like drugs, food, and many things, storage in a cool dry place is better. The effect of age and/or degradation appears to have a more deleterious effect on the hardener than the resin. But the real epoxy experts and chemists who develop and manufacture epoxy all seem to agree that old outdated materials are not as strong as fresh product.
I would trust their opinion on the matter of epoxy shelf life and performance more than the guys at Brownell's tech support.
