[myfamiliacc]

Did a small repair on my sister in law’s car, but when buffing it. I shipped the molding a bit, so I picked at it, and it just started peeling back.

The molding got the same attention as the rest of the door, besides the body work.


Scuffed the OG clear with 400 then a gray scotch bright
Cleaned with Wax/Grease clearer, dried
primer
wet sanded with 600
base then cleared.

You can see in the picture were I easily scraped the new paint off the scuffed OG clear coat.
No were else is it doing this, and I did pick at it at deferent spots, it seems to be only on the molding.

So my question is, could the factory be using some kind of additive on the just the moldings that could be causing the adhesion problem, like a flex agent or something?

and if so, what could I do to fix it?

Sand down to the plastic and work my way up, or sand down the or clear again and this time spray some adhesion promoter first?

[BarryK]

Only Idea I would have would be use an adhesion promoter.

I have not worked on a new car in so long not sure type of plastics the moldings are made of.

If you can shave a piece with a razor blade see if the plastics floats than it needs a promoter.
Sounds like you prepped it good so thats about all it could be.???

[baddbob]

Some of these plastic mouldings really dry out, you can see it when they lose their gloss. The mouldings may have absorbed alot of solvent from your basecoat then when you cleared it got trapped when it tried to come back out causing the basecoat to lose it's adhesion. Especially with black, people tend to put the base on really wet. This scenerio may or may not be the problem, just an idea. I've also seen some of these mouldings soak up wax and grease remover. Bob

[Bee4Me]

Man, You just are having the worst luck with some of these jobs.

I'm thinking it might be something in the plastic that caused the adhesion problem.I'm no chemist but some plastics release chemicals as they age and that may be the problem. Kinda treat it like a new f'glass part if you get my meaning.
After you sand it back off,I'd scrub it good with some Ajax or Bon-Amie cleanser before applying ad. promoter and use a water base pre cleaner instead of the usual solvent type. Then blow it off good with air to get all the water out. I use a inline air filter ON my blow gun that helps catch any residual oil from the comp. just in case.

[AC/DC]

Your title on this thread says paint not adhering to original clear coat. If this molding had a clearcoat on it, there would be no reason to use a plastic adhesion promoter. Did you paint the moulding on the car or off? If you painted it off the car(the proper way) did you perhaps flex the molding in the process of putting it back on? Also, did you maybe get the molding hot with the buffer? With that molding sticking out that would not be hard to do. From now on do not put the car together before you polish, always polish first.
Now, if you painted it on the car(the inproper way) the gap left by the two face tape which leaves the tape exposed is a problem. Nothing sticks to the tape and in the process of buffing it ripped it loose. If this was done in an airdry situation clears can be peeled off no matter how well the prep if it is not completely dried.
Now one last thing, are you completely sure that molding had clear on it? Some moldings are the color of the car but have been dyed not painted. If it has been dyed then you would need to use a plastic adhesion promoter. Also remember that there is a different set of directions for painting raw(unprimed/unpainted) plastics. Refer to your jobber/paint supplier.

[myfamiliacc]

[QUOTE=Bee4Me]Man, You just are having the worst luck with some of these jobs.
[QUOTE]

Ya, tell me about it

And it seems like it's the quick jobs that give you most trouble, but then agian that should tell me something in itself........"a good job isn't quick"


On this one I did do a short cut as I left the molding on to paint.
The repair was a deep scratch/grove between the molding and handle

after the repair I contenued with painting, the molding as well as most of the door was scuffed the same. I didn't thing of useing any adhesive promoter becouse I was scuffing the clear on it, not the plastic.

During the buffing process, I did have 3m green tape on the molding to protect it, and i'm sure during the pulling of the tape is when the first "nick" started, bur from there I was able to just run my finger nail accross it and "scrape" the paint off with ease, so I didn't think it was just becouse of the tape.

The only thing I could come up with is that when it was last painted, an additive was used on just the moldings that was cousing proublems with the new coats.

I'm going to just pull off the molding and sand it down and start from the bottom up.

Thanks for all the good advise and impute

[Bee4Me]

IF they even preped the moulding right to begin with.
Look's like they didn't as the previous clear peeled off so easy.

I understand your wanting a "quick buck" but as usuall, It end's up biting you in the *****.
I'm going to do my daughter-in-law's Hyunday rear quarter BUT,
I told her "It might take awhile"
Trying to figure out how to clear that thing as the upper part has a strip that run's up the back glass side into the top and I don't want to blend it in IF I can keep from it.
May just tape it at the pinstripe and use the stripe to cover the break.

[jcclark]

Sometimes these mouldings can be saturated with silicones like
Armor-All or other vinyl restorers. Are you sure that was never done to this
car? maybe by a previous owner? I've seen some of the older ones really
drink up this stuff making it next to impossible to get rid of it.
That would definitly do it.
Of course that wouldn't be the case if they really were clear coated originally.
(just another idea for thought)