I'm used super glue beginning to cure within a minute. I have a batch of tiny single-purpose Super Glue Gel tubes from 3M of unknown age. I want to use them to fix tiny parts to a circuit board. So the blob is exposed to a lot of air as opposed to disappearing between two mated parts. But after an hour it was still unset, and I could wipe most of it off.
Why? Too old? Bad batch? Too big a sample? Wait longer? Humidity too low?
Relevant portion of instructions: "Hold until set."
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