I had a friend's shop paint my 1991 Taurus SHO bumpers (I have two nearly identical cars, same bumpers) with single stage OEM paint. The metal that was painted is fine, but the bumpers are starting to peel now. Both bumpers started peeling at at small groove, so I'm assuming that part wasn't sanded and prepped well, but I'm not sure. The other point at which they started to peel was in the middle of an open area of white paint with no grooves. Again, that makes me think that it wasn't primed and sanded properly. Or it's possible that it's a product of not baking the bumpers to cure the paint. I'm hoping someone will be able to give me some more insight on this.

The shop is going to repaint both rear bumpers for me with the same OEM single stage paint, but I want to make sure I know how to properly apply single stage paint so I can convey it to them. Then they'll be able to figure out what they did wrong and correct it this time. They're used to doing two stage paint. I think the single stage paint is an enamel urethane, but I'm not really sure. I'm hoping my car's year and model will tell which kind of paint it is. It's a white Taurus SHO, which in that year used the single stage paint. I'm just not sure which type of single stage paint.

Thanks so much for any help you can provide.

It's hard to tell what went wrong.... I mean it's not like we area seeing "before" and "after"pic.s here. Sure, it could have been poor prep., possibly sanded down to bare plastic with no adhesion promoter, and on and on. If the shop normally shoots base/clear a single stage urethane should have been no big deal. I am sure they are shooting some SSU now and then just in the course of regular business. As to exactly what was on your the early 90s was a transition into the base/clear systems so you'd have to do some more research. You can start with your largest or highest volume paint jobber (that's a automotive paint vendor) as they might know...
Just some advice on this too. I run a rather busy wood restoration shop. The last thing I want to hear is a consumer telling me how they went online and got instructions and will tell me "how" to refinish their furniture. Just the fact that they are reshooting this for you speaks volumes about a shop that is trying to make it right. Give them a chance to correct this "their way" first....

Thanks.

I know what you're saying, but this shop barely does any paint and body work, and mine was their first single stage paint job. My friend owns the shop. He said he knows nothing about paint. He's trusting his mechanic from El Salvador who paints and does body work. They're reshooting both rear bumpers because they know they screwed up on both, but they don't know how they screwed up. If I had their tools, I'd paint it myself. I research well and practice and do things right. His mechanic on the other hand, not so much. He doesn't speak English, so it's hard for him to do research. He's messed up on my cars several times and had to fix his mistake and is sometimes unable to fix it. Either I or another mechanic will fix it in those instances.

Me researching this is to help them out, because they just lost their best mechanic and they're swamped. And I don't want them having to do the job again in 6 months. I've been asked to research things for them before, so it's not an insult to them.

I'm trying to get the stages one goes through to apply single stage paint to a plastic bumper. Then I'll pass that along to them. Pretty simple. They may find there's a step they didn't know about.

Also, I know my car has a single stage paint. I just don't know the specifics. I was just asking about the specifics in case you needed to know them to answer my question.

Hope that explains things a little better.

Well, geez, that's a mess then. You are having a shop paint your car that is telling you they no nothing about paint???? That's a recipe for disaster. Okay, Chris, made a nice "sticky" at the top of this forum about plastic bumper repair. All you do is leave out the repair part and the rest of the pre/paint work is pretty much the same. Once you're past sealer instead of base/clear they are going to be using their SSU (and yes, that means single stage urethane). One extremely critical thing I will mention here... IF they stripped that bumper down to bare plastic and did not use an adhesion promoter that is probably the problem. Other than that, with guys with so little experience, it could be just about anything.

DarrelK wrote:Well, geez, that's a mess then. You are having a shop paint your car that is telling you they no nothing about paint???? That's a recipe for disaster. Okay, Chris, made a nice "sticky" at the top of this forum about plastic bumper repair. All you do is leave out the repair part and the rest of the pre/paint work is pretty much the same. Once you're past sealer instead of base/clear they are going to be using their SSU (and yes, that means single stage urethane). One extremely critical thing I will mention here... IF they stripped that bumper down to bare plastic and did not use an adhesion promoter that is probably the problem. Other than that, with guys with so little experience, it could be just about anything.

Thanks so much. I greatly appreciate the info.

This is a mechanic shop, so the owner knows how to fix cars, but knows nothing about paint, so he leaves that to one of his mechanics who paints. The mechanic knows how to paint, but I don't get the impression that he's really well skilled at single stage. I don't think he knows much about single stage at all, really. I think he tried to paint it like a two stage.

Thanks again for the info. That's a big help.

I would have to assume they didn't use adhesion promoter. I see a lot of that in my world. Its key in getting paint to stick to plastics

mix master mark wrote:I would have to assume they didn't use adhesion promoter. I see a lot of that in my world. Its key in getting paint to stick to plastics

I'm starting to think the same thing.

Accelerant and Hardener (are they the same thing?)

I'm a little confused on something. I was watched a video of a professional applying single stage urethane to a metal piece and he used an accelerant and a hardener, if I remember correctly. I may have the terms incorrect. He said activator, too, which to my knowledge is what hardens epoxy, so I assumed he was talking about the hardener or accelerant.

I was wondering, should an accelerant and/or hardener be used in the single stage paint when painting a bumper, or is that only for painting metal pieces?

Thanks so much.

those are 2 different products.. you add hardner to any 2K product, accelerator speeds up the curing process and is generally an optional product and must be used carefully and sparingly. It can knock down gloss levels in colors and clears

Thanks, that's helpful.

Last questions:
1. This shop doesn't have an oven to bake the bumpers in. Is that going to be a problem for this single stage paint?

2. Are there any steps that need to be taken since they don't have an oven?

There was one other question, but it just left me. Oh well...if I think of it, I'll post again. Thanks again for the help. Much appreciated.