A warning on "paint wrinkle"!!!

[Michael Stoops]

Re: A warning on "paint wrinkle"!!!

What do you recommend for plastic bumpers when using m105/205?

Treat them the same way you treat the rest of the car. Same pads, same tool, etc. Just make sure you don't apply undo pressure, that you don't dwell in one area too long, and you don't start generating a lot of heat in one spot. It's always a good idea to stop buffing and simply touch the paint with your bare hand as you go. If it feels a little warm you're fine, but if gets hot then back off and let it cool down. More importantly, be aware of what you were doing just before it got hot and back down from that process - time, pressure and speed. You do not want to get this substrate really hot because it dissipates heat differently than steel or aluminum, and that's part of why you can get into trouble here.

[Show N Tell]

Re: A warning on "paint wrinkle"!!!

What do you recommend for plastic bumpers when using m105/205?

[RaskyR1]

Re: A warning on "paint wrinkle"!!!

Rasky, I really appreciate your posting this, because it could have easily happened to me in the upcoming days.

It kind of sounds like the most conservative thing to do with plastic bumpers if you are going to buff them is to use a rotary with a 4-inch pad; unlike the DA, which is more aggressive with a smaller pad, the rotary is less aggressive with a small pad, because the outermost part of the pad moves at fewer cm/second than with a larger pad at the same rotational speed. Still, caution is needed, because it sounds like the paint on the flexible bumpers doesn't adhere as well as to metal.

Small pads tend to work well on the shape of most bumper covers too. I think the most important thing is to reduce your speed, lighten up on the pressure a bit, and definitely don't stay on one area too long or make to slow of a pass. This will require more time to correct, but it's better than risking paint wrinkle.

[Mary S]

Re: A warning on "paint wrinkle"!!!

Rasky, I really appreciate your posting this, because it could have easily happened to me in the upcoming days.

It kind of sounds like the most conservative thing to do with plastic bumpers if you are going to buff them is to use a rotary with a 4-inch pad; unlike the DA, which is more aggressive with a smaller pad, the rotary is less aggressive with a small pad, because the outermost part of the pad moves at fewer cm/second than with a larger pad at the same rotational speed. Still, caution is needed, because it sounds like the paint on the flexible bumpers doesn't adhere as well as to metal.

[Garage Troll]

Re: A warning on "paint wrinkle"!!!

Thank you.


I still find myself using the rotary on heavily swirled bumpers, but I'm definitely more cautious now and I'm always checking to make sure the panels are not getting warm/hot.

Rasky

No problem!

I often wonder how much of this flex agent is in the paint on my polymer panels.

[Andrew C.]

Re: A warning on "paint wrinkle"!!!

Hmm, I know that twice doesn't make a pattern, but I wonder if it is something to be more cautious of with Honda paint.

I was thinking the same thing Mark. Rasky was working on a Honda, so was KerrinJeff, and the post by benedict was an Acura, which is made by Honda.

I know from working with Hondas before that their paint typically tends to be pretty soft, especially with some of the newer models like the Fit.

Like you said Mark, twice doesn't make a pattern, but I'm just wondering if the typical delicacy of the Honda paint, plus a plastic bumper and just a little bit of heat is all you need to get this?

The pontiac in the autopia forum was in the sun, so the heat from the sun probably added to his issue.

[fullbirdmusic]

Re: A warning on "paint wrinkle"!!!

I have a spot on the hood of my Astra that looks very similar to this, just not wrinkled. It looks like the paint just sort of broke, like a window. I'll take a picture today when I get home and show what it looks like.
At first, it looked like an etching. I polished it, and the etching went "away" and sort of turned into this. But it's on the hood!? I'll have to post a picture to get a good answer, but do I need a respray? Great...

[RaskyR1]

Re: A warning on "paint wrinkle"!!!

I just saw this thread and wanted to make a comment. Rasky, thanks for the post and warning. It really is a rare trait nowadays for someone to step up and say "oops, look what I did! Watch out everyone!" I for one would trust you with my baby any day.

Thank you.


I still find myself using the rotary on heavily swirled bumpers, but I'm definitely more cautious now and I'm always checking to make sure the panels are not getting warm/hot.

Rasky

[Garage Troll]

Re: A warning on "paint wrinkle"!!!

I just saw this thread and wanted to make a comment. Rasky, thanks for the post and warning. It really is a rare trait nowadays for someone to step up and say "oops, look what I did! Watch out everyone!" I for one would trust you with my baby any day.

[bmrfan]

Re: A warning on "paint wrinkle"!!!

Paint wrinkling sounds like a classic paint adhesion problem on plastic substrates. In addition to flex agents, its very common for adhesion promoters to be used when painting plastic substrates.

Too make things more complicated - auto manufacturers use different types of plastics and often the adhesion promoter is optimized for a specific plastic / paint combination.

Bottom line - be careful polishing painted plastic parts.

[Michael Stoops]

Re: A warning on "paint wrinkle"!!!

Rasky was using a rotary in the original post to this thread, but don't think for a minute that this can only happen with a rotary buffer.

As kerrinjeff mentioned, he experienced this using a 4" cutting pad on a D/A. That combination can be quite powerful since using a 4" pad on a D/A concentrates all the energy into a very small area. If you then run the tool at fairly high speed, use heavy pressure and a cutting pad, it is amazing how much heat you can generate with a D/A. Dwell on one spot for a bit longer than usual and you really increase the chances of this happening.

There is definitely something going on with the paint used on these flexible bumper covers. Whether it's the flex agent added to the paint causing the paint to be a bit more delicate, or whether it is some how compromising the bond of paint to panel isn't 100% clear. But exactly what is causing this less important to a detailer than the fact that the situation occurs at all.

When working on these areas just be extra cognizant of the area you're working on. This substrate does not dissipate heat the same way steel or aluminum does. And while we don't normally think of a D/A as creating a lot of heat on the paint like a rotary does, it certainly can in this case (4" pad, cutting pad, pressure, speed, dwell time) and it can bite you before you know it.

Used properly, both a rotary and D/A are perfectly safe on these flexible panels. But a little higher level of caution or awareness here is definitely a good idea.

[Brook]

Re: A warning on "paint wrinkle"!!!

Hmm, I know that twice doesn't make a pattern, but I wonder if it is something to be more cautious of with Honda paint.

Before I started studying detailing and maintaining paint finishes I usually took my wife's 2005 Honda Odyssey to the local carwash and used the high-pressure soap/rinse gun. The car wasn't that old and the paint was in great shape when nonetheless, the pressure gun took off a 1/4" x 2" strip of paint from the front bumper, exposing the black rubber material underneath. There wasn't even any kind of primer. Fortunately, some touch-up paint from the Honda dealer covered it sufficently so that one wouldn't notice it unless one knew where to look.

[Fly Bye]

Re: A warning on "paint wrinkle"!!!

Does this mean it can't happen if using a DA?

http://meguiarsonline.com/forums/sho...6&postcount=15

[Mary S]

Re: A warning on "paint wrinkle"!!!

Is the fiberglass flexable?


My bike has plastic panels, and I've never had a problem with cleaning/polishing them as they are pretty firm/sturdy.

His bike panels are rigid. The other parts I mentioned on my car and his are soft/flexible, though.

[Markus Kleis]

Re: A warning on "paint wrinkle"!!!

Same exact thing happened to me, also on a Honda, except using the PC with 4" cutting pad.

Hmm, I know that twice doesn't make a pattern, but I wonder if it is something to be more cautious of with Honda paint.

I used a rotary quite extensively on bumpers and have never run into this, but like Rasky said, it can happen to anyone, anytime.