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-   -   Weird clear problem (http://www.hotrodders.com/forum/weird-clear-problem-53659.html)

ChrisMiddleron 12-07-2004 09:07 PM

Weird clear problem
 
Hi I painted my Blazer a couple months ago.

http://img84.exs.cx/img84/7272/dsc0131912yn.jpg

I used a Napa crossfire CC5000 clear. A week after the paint job I began wet-sanding and buffing. The car had a mirror finish.

http://img84.exs.cx/img84/4818/dsc0133012ju.jpg

Recently though the clear has begun to get rough. It has almost like a dry clear spray look to it a couple months after wet-sanding and buffing.

I used a clear safe wax and everything like that also. Does anyone know why the clear would start to do this?

I cant get a good picture of it though. :pain:

MARTINSR 12-07-2004 09:09 PM

No problem, I have time. :)

ChrisMiddleron 12-07-2004 09:14 PM

It isn't cracking or anything. Its just getting rough on its own. Its been sitting in the garage forever

MARTINSR 12-07-2004 09:26 PM

The description you give doesn't sound like anything I can think of.

Tell me, does it have a "leathery" look? If you look real close does it have a look like the top layer has tiny, tiny wrinkles? Is that the rough texture you are talking about?

If it is,that would be shrinkage.

Centerline 12-08-2004 06:42 AM

You might have sanded through the clear and your looking at UV damage to the base coat. Had that problem in a couple areas on my 41 a few years ago. If that is the case the only real fix that I know of is to sand the panel down and repaint because re-clearing won't help the damaged base coat.

I'm not saying this is your problem but it is something to take into consideration. MARTINSR or one of our other pros should be able to tell you for sure when you can post some better pics.

Centerline
Moderator

ChrisMiddleron 12-08-2004 01:12 PM

MartinSR It does look like small wrinkles. Not wrinkles like the clear is cracking andd stuff but wrinkles like a small bumpy rough texture the clear has.

The tiny "Wrinkles" are spreading on every panel though. I would try and take a picture of it but the camera still shows the car like a mirror.

If the clear is shrinking does that mean that the clear will begin to crack and all that bad stuff?

MARTINSR 12-08-2004 01:53 PM

It wasn't atomized properly and is full of solvents. This is caused by "bombing" it on to make it "flow". I will preach and preach about this. You just can't expect a product that is applied real heavy to cure and flash properly.

That being said for everyone else :) Now, your problem. It is hard to say how easy this clear is to cut and buff now after a few months. You would want to take a panel at a time or even a section of a panel to see if you can do it. Many times the clear gets too hard after this long and buffing can be a real bear.

But if you were to cut it with some fine paper, 1500 or 2000 and let it breath like that for a few days then buff it you can probably save it. Even if you recut and buffed it without the wait it may work because it has shrank down. But my concern would be that the solvent still didn't get out, it just softened the film, and maybe the film under that as in paint and primer. If it shrank that much, I would say a good thing would be to "open it up" with the 2000 and let it breath.

When I was a rep for NAPA M-S the most extreme case of this I have ever seen was a guy who painted a Mustang convert. This was at a prison, it was painted by a "resident" of the prison for a commanding officer. :) Needless to say he wanted it right. Well first off, he used too slow of reducer in the color, then he bombed on the clear (NAPA M-S clear) so much that it had foggy stripes. Now, this clear was REAL hard to run so he really could pour some on,and he did. So, he color sanded it the next day and painted and cleared again. Again, it had the foggy stripes. Now,mind you, I had never seen anyone apply enough of this clear to get those stripes, he was REALLY bombing it on. So then, he sanded the thing and I came by to correct the problem.

When I got there he had already sprayed the base I showed him how to shoot the clear, everything was cool. One problem, I didn't now he had applied so much material. And, I didn't know he had used the super slow reducer in the color. Well, he buffed it after a few days and it shrank. After he called me and I learned of all the material I told him just what I have told you. He totally sanded it with 2000 and set it outside. The darn thing was still soft a week later! You could stick your fingernail into it! And this was in about 100 degree weather. :pain:

SOOOO, he left it for a couple more weeks, it finally hardened up and he buffed it. I saw it months later and it still looked good. But I sure wouldn't put much of a warrantee on that one!

ChrisMiddleron 12-08-2004 10:10 PM

Well the only thing that MIGHT have had a chance to be put on heavy is the last coat of clear because I wetsanded and stuff in between coats and stuff. The wrinkling aint really bad yet. Im hoping it dont get worse. Ill just probably wetsand it in a few months pinstripe in then reclear. Wait a few months for the clear to harden. THen wet-sand and buff.
That being said though the only side that is bad rough is the passenger side. THe other panels are still decent.

Do you think there will be probs with me reclearing after a while?

MARTINSR 12-08-2004 10:39 PM

No, reclearing will be fine. How many coats of clear did you put on between sandings" How much total clear did you apply, a gallon or more?

ChrisMiddleron 12-09-2004 12:05 AM

I only put on 3 total coats of clear then a couple days later I started wet-sanding and buffing.

MARTINSR 12-09-2004 07:52 AM

That isn't much clear, that is for sure. I do see that little compressor sitting there, did you use that? What kind of gun?

If you were using that little compressor and an HVLP gun that needed 15 CFM even one coat could have a ton of solvent in it.

ChrisMiddleron 12-10-2004 01:11 AM

That might be it here the compressor info.


http://www.homedepot.com/prel80/HDUS...yaircompressor

It says 6.6/5.8 SCFM @ 40/90 psi.

Can you explain how that works? How lower cfm makes the paint gun spray high solvents? I use a cheap gravity feed spray gun. It does a good job though.

MARTINSR 12-10-2004 07:52 AM

Read this "Basics if Basics" Atomization (click here). It doesn't "create" any more solvents. What it does is no atomize so the paint (clear, primer, whatever) is not broken into smaller droplets allowing the "solvents" (thinners, reducers) to evaporate as the paint hits the car. CFM is the "V" in HVLP, VOLUME. That means the "amount" of air, not pressure but the amount. Sort of like comparing a super high pressure water hose with an ocean wave. You need a lot of air to "BUST" up the paint into smaller droplets as it leaves the gun. If you read the "Basics" thru, you will have a good idea.

Don't feel bad, this is a common error.

BarryK 12-11-2004 04:52 AM

This problem has nothing to do with the clear! The dead giveaway?
How long it took to occur.
Solvent was comeing up from deep down.
A couple of things will cause this.

Very common on Black, Dark blues and some reds as they are slower drying colors and piling on, to short of flash between coats, using to big tip for base. using to fast reducer for the outside temp in base, ANYTHING to trap solvent in the base, in other words.

Second cause but more rare is a lacquer sealer being used or a sealers with trapped solvents.

MARTINSR 12-11-2004 09:24 AM

Barry, I don't know about "nothing" with the clear,it appears to me the clear would be at fault as much as the rest. After seeing the compressor and the HVLP were used, I didn't think to address the rest. But you are dead right, the base, the primer, if that compressor/gun set up was used, there is a lot of solvents trapped in that film!


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