While I haven't used the two part products that seem to be used most often in bow making, I have been using epoxies for other hobbies for many years. Best thing to do is of course call the mfg. Most of the glues I have used tend to be good for a year or two if kept in a "cool, dry, dark place". If you keep them in the fridge, you can double that depending on the product. I've also found that the faster setting products tend to degrade faster, ie five minute epoxy goes "bad" faster that two hour stuff. What I have noticed is that when the glue starts going, it takes longer and longer to set, the end result stays a bit tacky, and the glue itself begins to turn yellow. If you don't mind the color, just add a little more hardener to set it better. Again I have not used epoxies for bow making where structural integrity is not only crucial for the bow to survive, but personal safety is also involved. I'd store my cans in the fridge, and then replace once a year depending on mfg recommendations. I also agree with Banoch, it is an exothermic reaction. The more volume as a whole or the less surface area will effect how fast the product will go off. Heat helps catalyse, that is why people use hot boxes.
Swamp
