Last weekend I set out to skincoat my kayak (it is kevlar and was the kevlar was exposed in some places).
Carefully cleaned it with acetone.
Got kitchen scales out. Decided to mix up 200ml or so of resin. Poured 200gm of resin into one cup. Carefully weighed the hardener. mixed them very thoroughly, then spent 30min painting them on the waterline part of the kayak.
Seemed to be taking a long time to go off.
Cold horrible dread came over me. I'd carefully weighed out enough hardener for 100gm of resin, not 200gm . . .
Been waiting all week to see if it will go off. The bit in the mixing cup, in the warmth, went glass hard overnight. 5 days later, the part on the hull has gone off, but because it took so long, it has run, leaving bloody great runs down the side of the boat. I have a long hard job ahead of me scraping those off.