I put a coat of flat black on the back of a hood, then sat it under some flood lights I was using to help dry parts as the weather was cold. Ten minutes later- 'this isn't doing anything, I'll move the lights a little closer to dry it faster'. Thirty seconds later I look up and wonder what happened to the hood, all that was left on the bench was something resembling a prawn chip
Lesson learned: patience. And never underestimate the power of heat when it comes to flat black paint on plastic