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So I really dont have any clue how it happened. So A painted body I have has been flaking off leaving perfectly clear lexan exposed again. It had been happening just around the edges but it started to spread all over the place. At this point, the paint was just flaking off just from simply rubbing my finger over it. Well trying to salvage the paint from completely flaking off, I decided to spray some backing paint to help hold it on. Well it worked but what I saw after made no sense. Almost every bit of the paint looks like a shattered windshield with cracks going everywhere. All the crack lines have a whitish color around it even though I sprayed it with a black color.

all I know is ive only had 1 run that involved a few wrecks and this is what it ended like. I'd just like to have some idea what happened before I talk with the painter.

Doesn't sound like lexan paint! What paint were you using?

Was the body washed first?

I bought the body pre painted.

I've also bought another body from the same painter but its not chipping off like the this one

Any fluorescent colors or candy used that you know of?

Since you don't know what paint was used, I think you'll have to assume it was not Lexan paint.

The body this was on has since broken into several pieces, I'm starting to wonder if the body was even lexan to begin with.

Little mad over this as the paint was quite nice :/

Did it ever get near brake cleaner, motor cleaner etc? I have had bodies practically shatter after being "cleaned"

Same here, I tried to clean a jeep body last summer and used everything to get the paint off.

In the end it was nothing but a brittle body and I chucked it. Bought a new one and have yet to paint it.

DMAT wrote:The body this was on has since broken into several pieces, I'm starting to wonder if the body was even lexan to begin with.

Sorry to hear that...I've had that happen with acetone and Pactra paint thinner on Lexan. This might not relate to you, but don't anybody try those things on Lexan; just for info's sake.

I would guess the painter didn't us paint specifically for polycarbonate, which has flex agents. The painter probably used plastic paint which works well until the body starts flexing, also if body was not washed and scuffed it could effect the adhesion.

When you sprayed the backer you introduced a solvent to the old paint which softened it and caused the cracking and fogging. When applying a topcoat you must always make sure the paints are same brand and compatible.

As far as the body being brittle not sure other than exposure to chemicals such as brake fluid or possible a reaction between the two paints. I have had bodies become crazed and crack at the seams due to prolonged exposure to brake fluid and had other bodies come out fine.

Been custom painting for over 20 years, and have seen it all. Lately however, I have seen ALLOT of paint falling off of bodies, more than I would expect. I can only assume that something has changed that would effect the integration of newer paints into newer plastics. I recently tried Tamiyas (very expensive) new lexan paint. Just plain old black on a well cleaned body -flaked off horribly. Tried some different SPAZ STIX paints, similar resuts. I am still having fair success with Pactra lexan paints, but a good hit or two and I am having sections pop off. The faskolor stuff is not much better and it is heavy. Doesn't seem to matter whether the body is scuffed or not. I can only assume that some of the plastic formulations have changed to make them cheaper or adhere to EPA requirements (paints too).
As for the cracking of the "lexan" after re-painting, too much solvent in the paint causing it to fracture where the internal stresses have caused microscopic structural damage. The solvent breaks down the molecular bonds (easiest ones first =where the stresses are), slightly swells the plastic, then as it evaporates slowly shrinks the plastic -causing the cracks. Sorry to hear it, but I too have lost several bodies to similar situations -J

Fyi, i discovered, completely by accident a way to get old paint of lexan. Not exactly sure what paint it effects as it was a prepainted body. Use the citris base cleaners u would use to get old stickers off thengs. I was cleaning some very old velcro residue of a shell and some of the cleaner was left on over night, as i went to rub the glue residue off my finger nail scratched the paint and it came of pretty easily. You have to make sure u coat it heavily and soak it over night so the paint looks sticky in the morning and it comes straight off...just thought i would mention this as its a safer and non chemical option then brake fluid...

If this is the same pre-painted body that you figured didn't have the proper Lexan paint (because it wasn't sticking), then that's why the paint came off quite easily. I doubt citrus-style cleaners would have much effect on the kinds of paint that bond to Lexan, like Pactra.

Nup this paint job was perfectly fine....i wasnt intending to take the paint of at all, paint job was good although i didnt like the scheme...anyway i will try it on one i have been trying to clean with brake fluid and see....