Auto body repair & detailing: paint cracking, painting a car, feather edge

Question
my husband is painting a car but right when he applies the paint it starts to crack, and he starts all over again its been already a month and is the same thing, he keeps sanding again, can u give me an advice. Thank you

Answer
He's using an incompatible topcoat over the primer- if he used a 2 part catalyzed primer surfacer, then he can't use laquer topcoat over it. Either that, or the pain underneath is so badly degraded that it needs stripped. You need to strip paint if it was peeling, and that is the reason for refinishing. The paint can craze at the feather edge. Bill