Not a pro but a decent DIYer........ I mixed up some carlite finish plaster to skim over some bonding yesterday and it went on fine (I gave the bonding a good soaking first, no PVA). However it seemed to go off in minutes. The stuff in the bucket was still loose but the stuff on the wall was almost unworkable in minutes. I did manage to get a smooth finish with water and a sponge , but only just. Why is that? I wanted to use this stuff to do some skimming on other rooms but I dont think I will if there is no time to smooth it out. Any ideas?