I had my '75 painted 12 years ago. My color choice was GM Code 78, Brite White Diamond, put on high end GM cars like Buick Riviera, Caddy's and a few others. This is a 3 stage paint; base color, pearl and a clear coating. The info the painter gave me at that time was;
PPG Color Code # DBU 5134/5135
PPG Clear Code # DCU
I want to do some touchup here and there and I went to a PPG dealer who said he couldn't reference the 5134/5135 numbers, but the WA9097 code I came up with somewhere along the line did work with his computer. This paint is really expensive and I would like to make sure the DBU 5134/5135 and DCU clear are the same as WA9097 and/or Code 78. Thanks.
Mike

 

12 years ago, You will need to DEFINATELY shoot test panels. There has to be some type of color change over the years...which is normal.

The key thing is to remember is that the base color has to be as close to perfect as possible....then you shoot your pearls in stages..over the base color...so then when you apply the clear...you can see what you base color looks like with one, two, three, four layers of pearl on it.

Not knowing if you know...so excuse me if I am telling you something you already know.

I use test panels that are about the size of a license plate.
When shooting your test panel...paint it with the base color (white). and make sure that your panel is COMPLETELY covered in white. Then when it has flashed off well, take several (4 or 5) pieces of masking paper and apply tape to them ( you can remove some of the "sticky" off of the tape by running it across your pants...so it wont pull paint off of your test panel) and apply this masking paper/tape to your test panel COVERING about 1-1/2"of the painted test panel ...leaving the rest of the test panel showing white...Run your paper width-wise...and not length-wise...so you can get several layers in the panel...Then take your next piece of masking paper/tape and go ABOVE the one you just applied...and repeat with your masking paper and tape until you have white showing about 1-1/2" or so. Shoot the pearl with ONE COAT...DO NOT GO BACK AND FORTH. Just shoot it in one pass....on the exposed white in your test panel... Remove the masking paper you just got pearl on...and it will expose the white pearl that has not been pearled. When the first coat of pearl has flashed off. Apply pearl over the exposed area of your test panel and now the white section will have one coat on it, and the previous coat of pearl will be coated again...thus making it have two coats. Repeat this until you have the test panel coated....and all masking paper removed. So now you will have a series of layers. showing you how many coats to aplly over your white to get to a correct color match. Clear coat this test panel to make sure. Because clear can change things...depending on how thick you apply it. If your white is correct...and the pearl applied show you how many layers of pearl you need to match the paint job...make sure that you paint it the same way that you painted the test panel....becasue if you do not do it the same way...it may come out lighter or darker...and this type of pearl job does require some blending techniques.

I know that you will have to go back and forth over the test panel when applying the pearl...when you get past the first section.....but I don't want you to go over the same spot more than once.... move you gun down and paint as you normally would....Just don't DOUBLE coat it...or it may change the pearls test panel.
"DUB"

 

Thanks Dub. I have decided to do the paint work on this car and the info you gave me is very helpful. This will be a great challenge and learning experience for me. I have clarified the paint code to be GM #78,
WA140B, Bright White Diamond, PPG# DBU 5134/5135 with a DCU clear.
When a coat flashes off is there a physical difference in the appearance on the surface that I would be able to see? It's been over 40 years since I did some real paint work on cars and back then it was acrylic laquers, etc..
Mike

 

Mike,
YES, When the basecoat and pearl coats are applied...much like lacquer...a medium-wet coat....NOT A HEAVY COAT.....and NOT A DRY COAT...that may be rough looking. You want to see that it is shiny-wet...but not soaking wet. Use a test panel to gain confidence and see how the paint reacts to your paint gun setting and style. AND...when the basecoat and pearl coats have flashed off....it will be dull with an "eggshell" texture....possibly the base coat may have a slight sheen to it.

Not knowing if you know or not...so forgive me if I seem a bit...insensitive.

The **** on your gun that controls fliud is important. In this case...I would turn it all the way in...so you have NO trigger pull...then back it out 2 to 2-1/2 FULL TURNS. Now my guns are HVLP gravity feed guns with a 1.3 head on it. If you gun(s) are different...you may adjust accordingly. BUT whatever you do...I personally/professionally do not advise that you have a FULL trigger pull when applying your basecoat/pearls and clearcoat.

Remember that thinner coats flash faster than ONE HEAVY COAT. Thinner in the last statement does not referecne to the thinner you use to thin the paint...but rather in reference to film thickness.

Also keep in mind...eventhough many other painters may do it a different way...which is fine. I am a believer that when I am shooting at a controlled air pressure...lets say 45psi. The controlled amount of paint coming out of my gun is being atomized by that air pressure. I would rather find that "sweet spot" in fluid volume that works best with the air pressure and correctly thinned paint, so I know that I am atomizing the paint correctly and allowing the finish to lay down slick....which also depends greatly on your travel speed with the gun, distance from the panel and the THINNER/REDUCER you choose to use for your CURRENT temperature at the time of painting. So your fluid setting on your gun at the air pressure you are set at can either atomize the paint into a workable mist...or basically shoot droplets of paint....which droplets can cause ORANGEPEEL...due to being applied to heavy. So you can have either BB's or golf *****...if you wanted to think about it in a magnified state. I prefer BB's.

It is a total balancing act...so that is why I mentioned TEST FIRST. I have been doing it so long it is second nature now. The only part that I have to adjust is my grade of thinner/reducer...because the paint system that I use in conjunction with my HVLP paint guns...I use ONE GRADE SLOWER reducer/thinner than what the temperature at the time of painting NORMALLY calls for. This is so that my basecoat has time to "flow" before it TOTALLY flashes off....and I DO NOT GET DRY SPRAY...when I am going from one side of the car to the other.

SO when I am painting...I am NOT TRYING to shoot it SLICK and DRIPPING WET. I apply my paint so that it is ...like I wrote above...a medium-wet coat....that may have very little texture in it...but when it flashed off...it is very slick and smooth..with very little texture, if any at all...and I DO NOT HAVE OVERSPRAY collecting on the other panels when it is ready for the next coat. Which confirms that my choice of reducer/thinner, fluid setting, and techinque is "right on the money".

And how do I know this...you may wonder....because when I tack off before the final coat of base..just to help pick up any lint or minor specks that the tack rag will pick up.....my tack rag is CLEAN...and does not have any color on it at all....that is how I know. But needless to say..if I have specks that will not come up witha tack rag...BEFORE my final coat of base....I wet sand them out CAREFULLY...depending on the color and other issues...which would take me days to type out.
"DUB"

 

Thanks DUB. This is all great information, well presented. I think working with test panels, as you suggested, is the best thing for me to do in getting used to this paint and the process as you have layed out. If I can develop a decent technique before getting to the car I'll feel better. You've been extremely helpful.
Mike