Forensic Paint Analysis

Just out of curiosity, I stripped some of the old paint off of my truck in various spots using a razor blade just to see what was underneath. My guess is this truck was last painted in the 80's. Metallic blue BC/CC.

Regardless of where I stripped the paint off I find the same thing. Little spots of rust everywhere between the primer and the color coat. Nothing showing through the color coat though.

Any thoughts on what would have caused this? Polyester primer soaking up moisture before the color coat?

 

Poor prep work for sure. It coulda been badly rusted on the surface before it was painted, too. It's hard to combat that.

 

Could have taken up some moisture. My guess would be either the rust wasn't removed completely, or more likely moisture in the air supply It would probably come through eventually.

 

What they said. Could have been clean metal that was primed with old style laquer primer, then sat way too long (months) in humidity, and moisture can penetrate that primer.

or could be epoxy primer over small surface rust, that will grow if it was primed on a humid day.

 

Thanks guys. It doesn't look like the metal surface underneath was ever badly rusted (or rusted at all). I'm guessing it's probably the old lacquer based primer. I dunno, did they have epoxy primer in the 80's? I don't remember any.

Well, I'm thinking somehow there was moisture that got trapped. Maybe the primer soaked it up or perhaps there was moisture in the air supply, like Tinbender mentioned. I guess both would explain why it seems to be over the entire vehicle.

 

I only mentioned the epoxy over a rusted surface, in case maybe you might have tried to do a quick fix on your truck, thinking that epoxy is a miracle sealer...it is not, when painting over any amount of rust.

 

Nope, no quick fix on this puppy. It's going down to bare metal.