Question about painting bumper fillers


85 Triple Threat
I picked up a nice set of bumper fillers from the junkyard a while back and when I originally went to put them on my car I sanded and prepped them and then just used automotive paint in a rattle can. The paint flaked right off when the filler bent just a bit. I was curious as to what everyone else is doing and using when they paint their fillers to keep them from the paint coming off.
I'm no paint expert but if using the flexible OEM fillers the paint needs a flex agent so it doesn't do what yours did.

I rattle can'd my fillers, but mine are aftermarket fiberglass ones and they don't flex so I can get away with just doing that.
Take them to a good paint shop and have them painted properly. It's obvious you didn't know what you were doing in this arena given you didn't know about flex agents. You should'a left 'em alone. Now, they'll have to undo the damage you did. Nobody likes to fix other folks' f-ups, and things may not turn out as well as they would have had you spared the rattle can.

In the future, if you care about your car and I will assume you do, choose your battles more carefully. Admit when you don't know something, and let a pro do it. Paint is a good example. Most folks wouldn't even dream of painting their car. You and your car will be happier in the long run.

No malice...

SEM Products make a flexible prime that comes in a spay can that works.

I used it when I primered my Monte Carlo front and rear plastic bumpers. I just got lazy and did not want to mix up primer just for those bumpers I had off the car. This stuff aint cheap I paid 10.60 a can for it, and I have a dealer account at the auto parts store. It works really well, but dont forget after you sand off that mess you created you are gonna have to clean a degrease those parts before you apply primer to them (Ask the guy behind the paint conner what you should use).

Flexible primer
part # 39133
Available at Carquest
The paint has to have the flex agent in it too. Same company(SEM) makes flex finish coats. Depending on how nice you want your car to look in the end(and your budget)- you may want to go w/strikeagle's advice.