Hi Wal
If you warm any laquer or epoxy it gets much runnier, the hardening process is also more thorough. But don't heat the epoxy until you've mixed it. I know an archery bow maker here who left her epoxy cans on a heating box she used to cure the resin and didn't notice until her bows started delaminating at a world champinship in South Africa. She had to fly out with replacement bows, expensive mistake!
cheers
Andrw