I installed a poly body kit and had the vehicle pained about a year ago, and I've noticed cracks in the paint along the edges of the door caps, and some stress cracks in the front bumper. I have heard that there is some kind of special process for painting or coating urethane, does anyone know what this process is?

 

Im guessing its a WW kit? I have the poly WW kit on my crx and when we painted it, we followed these steps:
1. We smoothed it out some with 600 grit or so, if its already smooth just scuff it lightly with a pad.
2. Get you some Bulldog Adhesion Promoter, it comes in a rattle can and in a can to shoot it through a paint gun. ( Be extra sure to read the directions of how long to wait, I think its like 15-20 minute time for it not to be tacky.)
3. I used High Build Primer and coat it good. After this I blocked it with 400 and cleaned it off very well. If needed add another coat of primer.
4. Then apply base coat and clear or SS paint. Then after the paint and a clear is dry do your typical wet sand and buffing. Im pretty sure you can use some flex agent but I didnt and havent had any issues with it yet. Hope it helps!

 

You could also use some Flex Promoter because I know those kits can flex a lot and cause paint to crack.

 

Where can I find this Flex Promoter product? I am having the kit pieces repainted, wish me luck..

 

SEMS makes a great flexible primer surfacer, it comes in either rattle can or sprayable qt. cans for use with a spray gun, this stuff is awsome i've been using it for 5 years now and the sh@# works, had a customer who hit a deer(actually drove over the damn thing) flexed the poly front pumper in hard and ripped the rear bumper clean off the car, the front bumper is still holding paint! the rear well not so well,lol as far as flex add both ppg and dupont have a variety, also SEMS offers a few plastic promoters and such as well, most parts stores cary the SEMS line hope this helps