Brittle paint

[tparker]

I painted my car a couple years ago and it came out pretty good. A few mistakes which I will fix later. But considering the savings, I'm satisfied.

The problem is I have already chipped it in a couple places. The original paint was hard as a rock. But this paint seems to chip easy. I thought urethane was supposed to be tough. I'm curious if it is possible to mix thee hardener in a way that would make it be brittle, easily chipped? I don't think it was the prep work, but maybe. Is this a common thing?

[moparroy]

I don't know what causes it but I have seen that. I swear my 2010 Challenger chips easier than the Charger of the same year - different color - same factory. Certainly the silver is harder to match well due to metalics.

What kind of paint did you use?

Where I really saw this was on a repair done on my wife's Town and Country. MInor front end damage required new fascia. I decided to have it fixed since she was not at fault. The place that fixed it used BASF paint - not sure what line. Soon after we got it back the fascia started to chip - and not small chips - big ones - through to the primer - nice grey chips on a white car. I picked at one and it seemed the adhesion was bad on the base. Here is where it got interesting for me. I decided to touch up the chips with my touch up gun. Started doing just the spots but it looked crappy so I masked and painted pretty much the whole fascia with an Omni base and clear. And I had not sanded most of the surface because that was not my plan. So I did not know what to expect.
I have not noticed one new chip on it since! Strange cause I thought an adhesion issue underneath it would chip just as easy with anything on top. Somehow the clear must be stronger or something. I figured I'd be taking the fascia off and repainting it - but it looks fine - some overspray at the edges but I never polished it either.