Polishing Lacquer with Metallic

[Steve M.]

Getting ready to paint a 1969 convertible in Riverside Gold with PPG Products (DP40LF, K36, DP40LF) Ready to apply DDL (acrylic lacquer). Have read numerous Forum and other documents on painting with metallic paint. I have a used bumper with probably a 100 mills of practice. I am using the high high temp DTL105 and the paint lays down well with very little 'orange peel'. After 30 days, I tried to polish and was not very pleased. These is not much to polish as you know. As I understand, you are not allowed to put on clear to have something to polish. I have a friend with a Goodwood Green 1967 and a $15K lacquer paint job that looks like it is bc/cc that is Top Flight but 'over restored'. Do not expect that kind of results but can only have that level of gloss with clear coat applied as final coat. Maybe I should just polish lightly and wax with no clear? Any comments on what I am missing, doing or not doing would be greatly appreciated. Thanks for any help, Steve

[Mark E.]

Re: Polishing Lacquer with Metallic

Steve,

Are you saying you are color sanding and/or polishing metallic lacquer with no clear coat?

Metallic without clear cannot be sanded/polished without almost certain risk of ruining the finish. Sanding/polishing upsets the metallic, leaving a streaked, mottled look. Only sand/polish non-metallic or clear finishes.

Lacquer dries with a satin finish (from orange peel), and typically requires color sanding/polishing for an acceptable finish. Instead of using clear and buffing, I believe the factory used ovens to reflow the lacquer a bit, then sparingly polished the finish. Results were mediocre, especially with metallic colors.

Over the years, I've seen a few cars judged which were resprayed in metallic lacquer with no clear. Since they could not color sand/polish, nor used an oven, they had a semi-gloss, orange peel finish with more distortion of image than even the typical mediocre original factory finish.

If your goal is a beautiful finish with little DOI, then use a clear so you can color sand and polish. Results can be mirror like.

If your goal is minimal loss of points during judging, your options with a metallic color are limited. Maybe you can find a master painter who can lay down the metallic coats with the right degree of wetness, using the right speed of thinner at the right temperature to give an acceptable lacquer finish without clear or polishing. Others may have ideas about this.

[Domenic T.]

Re: Polishing Lacquer with Metallic

Mark is right, but I polished my 65 SS that had acrylic laquer. 2 kinds of laquer Acrylic and straight laquer. The acrylic (which was the later) was supposed to protect the pigment with acrylic which back fired later as the acrylic got old. The metalic, if applied correctly is supposed to sink under the acrylic coating. That leaves very little to sand and polish. Clear was the answer, but back then some clear was a mixing clear. I did sand and buff my my acrylic. Acrylic laquer would check or spider web aaas it aged in the sun.
Also metalic will change color by a shade or more if it is not sprayed at the correct air pressure. The pressure determines how deep the metalic sinks.
I had metalic added to straight laquer in the 50's and it came out good. Straight laquer was better than acrylic laquer in my opinion.

Dom

[Steve M.]

Re: Polishing Lacquer with Metallic

I appreciate the feed back. I understand that with metallic there is very little clear to polish and the issues that can occur if one sands through the clear above the metal flake. I have also sprayed out quite a few test panels with different pressures and different temperature thinners. As I stated in the original post, I am pretty happy with the results using the high temp reducer/thinner the paint lays down well with minimal orange peel. There is not a sufficient layer of clear to really sand/polish to obtain the deep shine that one can obtain from sanding/polishing solid color lacquer. Does NCRS allow clear to be applied on top of the paint to have something to polish or is 'what you see is what you get' with acrylic lacquer acceptable for judging? Any thoughts/comments from other that have done this would be greatly appreciated. Steve

[Patrick B.]

Re: Polishing Lacquer with Metallic

When I painted my 70 Corvette with acrylic lacquer many years ago, I mixed the Bridgehampton Blue metallic 50/50 with clear for the final costs. It did not look clear coated, and it could be carefully wet sanded and polished without messing up the metallic grain. I thought that was the standard method for painting metallic lacquer at time.

Mark is right, but I polished my 65 SS that had acrylic laquer. 2 kinds of laquer Acrylic and straight laquer. The acrylic (which was the later) was supposed to protect the pigment with acrylic which back fired later as the acrylic got old. The metalic, if applied correctly is supposed to sink under the acrylic coating. That leaves very little to sand and polish. Clear was the answer, but back then some clear was a mixing clear. I did sand and buff my my acrylic. Acrylic laquer would check or spider web aaas it aged in the sun.
Also metalic will change color by a shade or more if it is not sprayed at the correct air pressure. The pressure determines how deep the metalic sinks.
I had metalic added to straight laquer in the 50's and it came out good. Straight laquer was better than acrylic laquer in my opinion.

Dom

Hy

[Timothy B.]

Re: Polishing Lacquer with Metallic

Steve,

You ask a very good question, I remember what Pat say's about the clear in the top coat. Why don't you get in touch with one of the NCRS paint guys and see what they have to say before you spray anything.

[Domenic T.]

Re: Polishing Lacquer with Metallic

Steve,
I remember doing what Patrick did (mixing clear with final coat). I did have a problem doing that once (only once) and that paint supplier said it was a mixing clear, or the wrong clear.
Now, I did shoot a 2 part clear coat over laquer and it came out great. Also a 2 part clear coat can resemble acrylic laquer if applied a bit dryer. My BC/CC resembled acrylic in a few areas that were not seen. Problem is the 2 part clear coat is soooo much harder than acrylic and does not buff out like acrylic. It can be buffed but to get it to look like glass requires wet sanding with at least 2500 grit.

Dom

[Steve M.]

Re: Polishing Lacquer with Metallic

Thanks to all that took the time to respond. I am going to try a test panel and mix some clear with the final coat and see what that looks like. Lucky I went ahead and picked up the last gallon of clear as the PPG store was getting rid of all things lacquer. Thanks Again, Steve

[Timothy B.]

Re: Polishing Lacquer with Metallic

Steve,

FWIW, information is free and I would get in touch with one of the NCRS paint experts before you use any product especially that hard to find lacquer.