I'm painting some 1/16" plates of aluminium black. I gave them a wipe down, and used some generic primer and black spray paint. (I originally started off with a paint gun, but it broke). As the plate dries, it starts to crackle in some areas, but not all over. Any ideas what is going on?
I've never had this problem painting steel, or wood.
Do I need a different type of primer, specifically for aluminium?