I know body filler 'air dries' but I'm having an issue.

The car was painted, sealed with 2k, and shot with bc/cc. In certain spots the paint is lifting, blistering in the sun. I'm curious if the problem is gasses escaping from the body filler. Do you guys bake the filled parts before sealing?

I know the other possibility is solvent pops because of layering coats too quickly and not adhearing to flash time.

-- Joe

 

sounds to me like a paint issue. i worked at a body and custom car shop and we never baked the areas with filler on them.

 

yea i agree with red92bird at school we never baked just parts with bondo on them. i also think its somekind of adhesion problem.

 

might be incompatible primers and paints?

 

Did you wipe it down with wax & grease remover right before painting?

 

Did you have the car with body filler showing outside on a wet day, with high humidity?

 

Definatly is a Paint problem .. I bake stuff with bondo on it all day with no problems ..(even on plastic bumpers)
Sounds like a few things
the metal was not properly prepared.
poor quality primer ( was it a name brand PPG , Dupont, Spies ... ectt..? )
incorrect primer mixture / incorrect flash time.
primer not intended for bare metal.

 

Well. The car is made out of SMC, not metal. It was sanded with 400 down to the SMC. NO existing primer/paint at all was present, because well, I didn't want a chemical reaction and paint bubbling.

It was sealed with sherwin-williams 2k 'dimensions' sealer (dM 416 I think). Then shot with sherwin-williams 'dimensions' basecoat + clearcoat. (I have the formula if you want to see it)

Today myself, the painter, and the sherwin williams rep cut out one of the bubbles. There was no fumes of solvent, no water, It was complete paint to sealer. It revealed the SMC panel - and not in a spot where any repair was done. So it's a problem with the sealer not adhearing to the SMC.

We're still going back and forth, but I think what is going to happen is:

1) we're going to use an epoxy sealer rather than urethane sealer
2) We're going to wash the whole body down again, sand, wash, resand, rewash

One of the two, either sherwin williams, or the painter, or both is eating the job. The already agreed to repaint it - but I want to know why this stuff is bubbling off.

-- Joe