Have done something similar a few times, you get used to it and sometimes even learn... By the way most epoxy curing systems actually require a very precise mixing ratio and if away either way the leftover part acts first as a softener and then amine hardeners react with water and epoxy with just about anything but the mechanical properties will never be as good as with designed mix ratio. It is possible to design a catalytic epoxy system but I have not seen them commercially available. These would not require a very precise mix ratio and often you can change the pot life within some limits.

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