I'm working on a Universe Treadbolt repaint, repainting the whole thing black and purple. I used black Krylon Fusion for the base coat on everything, after full dis-assembly and a thorough wash with soap and water. Full week cure time. On the main jet body and the shoulder / thigh pieces I literally have to go to town with my x-acto knife to scratch the stuff, so that's good to go. But, on the nosecone assembly, his little chest flap doodad, and the hands the paint simply doesn't stick at all. A light brush with a fingernail and the stuff comes crumbling off. Testors arcylics stick better than this :| Any insight why these certain parts simply don't want to hold the paint? My prep process was identical on everything.