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Posted by: Lennies914 Jan 4 2012, 10:43 PM

So I've been preping my '75 for paint for the last two weeks and figured I was ready for primer. So I thought I'd do a quick wipe down with acetone and a tack cloth then shoot some primer. Had I been more experienced at painting I probably would have realized sooner that the paint (repaint) that I have been sanding on for two weeks was lacquer . The acetone imeadiatly started washing off the old paint. So hear is my question. Is there anything better and cheaper than acetone to wash down the car? Assuming that I cannot paint over the lacquer with acylic urethane.

Posted by: Jeffs9146 Jan 4 2012, 11:00 PM

The other night you said you were going to wipe it with Mineral Spirits...what happened?

Posted by: ThePaintedMan Jan 4 2012, 11:17 PM

Hi Lennie,
First off I need to say that I'm just a hobby painter, thought I've been doing bodywork for the past ten years when I first started working on cars in high school. So if any other more experience folks come along, I'd follow what they say.

Ideally, we would want to remove all of that lacquer first. Urethane CAN be shot over lacquer, but long-term prognosis is not usually good. Are you just shooting 2K over the lacquer? You can use a product called Prep-Sol by DuPont, but being DuPont, it ain't exactly cheap. Most wax and grease removers sold at the FLAPS would work, I think.

So you've already bought the primer? Acrylic? You'd most likely want to continue with lacquer for primer, color and clear, IMHO since thats whats on the car now. But, this depends on what kind of longevity you're looking for and how much you want to spend. I'm all about urethanes, especially in humid areas. Lacquer tends to absorb moisture over time - thats what its a bit outdated.

QUOTE(Lennies914 @ Jan 4 2012, 11:43 PM)

So I've been preping my '75 for paint for the last two weeks and figured I was ready for primer. So I thought I'd do a quick wipe down with acetone and a tack cloth then shoot some primer. Had I been more experienced at painting I probably would have realized sooner that the paint (repaint) that I have been sanding on for two weeks was lacquer

. The acetone imeadiatly started washing off the old paint. So hear is my question. Is there anything better and cheaper than acetone to wash down the car? Assuming that I cannot paint over the lacquer with acylic urethane.

Posted by: ThePaintedMan Jan 4 2012, 11:19 PM

QUOTE(Jeffs9146 @ Jan 5 2012, 12:00 AM)

The other night you said you were going to wipe it with Mineral Spirits...what happened?

You don't want to wipe with mineral spirits before applying acrylics or urethanes, right?

Posted by: Lennies914 Jan 4 2012, 11:30 PM

Yes, I've already bought the paint and primer. As for the paint thinner, I just bought that for cleaning my guns.

It seems to me that I was always told not to spray urethane over lacquer.

But I haven't painted in several years.

Yes it is 2K.

So I can finish cleaning the one fender with acetone (and re-prep it) then prime over it?

Posted by: rick 918-S Jan 5 2012, 12:09 AM

Your paint job is only as good as what is under it. I don't paint over a re-paint. Bad things can happen. Strip off the laquer first. When you go to wipe down the car use Dupont 3812 or 3919S.

http://pc.dupont.com/dpc/en/US/html/visitor/common/pdfs/b/product/dr/ChromaSystem/H-19295_3919S.pdf

Posted by: nathansnathan Jan 5 2012, 07:56 AM

The thing is, the original paint was lacquer, too.
In California, you won't be able to use lacquer, or buy it, I should say.
What you need is a "tie coat" to put between.

Posted by: Lennies914 Jan 5 2012, 08:28 AM

Thanks guys, I'll be washing off the repaint tonight.

Posted by: tod914 Jan 5 2012, 08:42 AM

Nathan, the original paint on our cars is baked enamel, not lacquer.

Posted by: rick 918-S Jan 5 2012, 10:19 AM

QUOTE(tod914 @ Jan 5 2012, 08:42 AM)

Nathan, the original paint on our cars is baked enamel, not lacquer.

Posted by: nathansnathan Jan 5 2012, 11:26 AM

I haven't been able to find a reliable source to confirm either way - I had had read that it was Glasurit Lacquer, this on 914club, but then it wouldn't be the first time the doctor was not right.
http://www.914club.com/bbs2/index.php?showtopic=287242&hl=paint

I'd read that porsche (not Karmann) used different systems based on color, like the red was a single stage, the blue was base/clear, but this was 924-specific.

Posted by: ThePaintedMan Jan 5 2012, 08:17 PM

I can't help confirm that either way.... well, either. But I do know that was a pretty common strategy for automakers back when. Some of their paints simply wouldn't work right as a two-stage, so many were single stage.

QUOTE(nathansnathan @ Jan 5 2012, 12:26 PM)

I haven't been able to find a reliable source to confirm either way - I had had read that it was Glasurit Lacquer, this on 914club, but then it wouldn't be the first time the doctor was not right.
http://www.914club.com/bbs2/index.php?showtopic=287242&hl=paint

I'd read that porsche (not Karmann) used different systems based on color, like the red was a single stage, the blue was base/clear, but this was 924-specific.

Posted by: scotty b Jan 5 2012, 08:48 PM

You need a wax and grease remover to wipe down with, do not use any type of solvent. That said, clean up the panel you wiped, make certain you sand out all of the wipe marks or they will haunt you, then prime and body work or seal and paint if it is where you want it.

Posted by: Lennies914 Jan 6 2012, 09:41 AM

Thanks for all the help guys.
I recruited my son to come over last night to help strip off the lacquer. After all, he is the one that wrecked my '74 and is responsible for me having to build a new car .
With his help we were able to get the car back down to it's original paint, one more full sand, and a coat of primer.
I'm really happy that I stripped it down, I was curious as to why it was repainted in the first place. It turns out that it was nothing more than a couple door dings and a small left rear corner repair.

I'll get some pics up soon.

Posted by: Lennies914 Jan 6 2012, 07:33 PM

First sanding

Ready for first primer coat

After stripping off the lacquer and got down to the original paint most of the body work seen in this picture was removed

primed