69, I gotta disagree. I do a fair amount of painting on my own..many times single stage, sometimes clear over single stage of various types of paints...That's a curing problem if it takes that long. It should be hard within a few days, unless it's below 45-50*, depending on the material used. Maybe ambient temp was part of the issue? I've found various enamels to be hard as a rock within a few days in 50* weather, and next day in 60* or higher. That paint, on his panel, didnt stick for some reason. If it wasnt cured, it would flex and tear if it was being "scratched" and had poor adhesion, not come off in small oval sections along the impact..That's dry enamel with poor adhesion. You get the same effect when a sandblasted pulley or bracket gets painted with ending enamel and there's still some contaminant on the surface. At the exact point of contact, the paint fractures, but it isnt bonded to the surface, so a larger piece breaks off. A correct finish will be dmamged only where the impact is..not out on either side of the impact too. I have found these enamels to be almost bullet proof on things like tractors, and bike frames, hand rails, etc..so I think it's a prep issue.