Paint and primer question - 1969 Tuxedo Black

[Kevin S.]

Hello NCRS,
Continuing restoration work on our 1969 Coupe and I am at a point where I am able to remove the chrome front and rear bumpers, exhaust bezels, front bumperettes and hockey sticks, front and rear side marker lights. I know that this car suffered a rear-end accident at some point in it's past. I also know that this car was repainted once and I assume that was connected with the rear-end damage repairs. I beleve the repairs and the paint were done at Murphy Chevrolet in Milwaukee, WI based on a tank sticker I found when I dropped the gas tank. Murphy Chevrolet went out of buisness around 1978 so the rear end repairs and repaint were done prior to that, best guess.

Primer located under the rear exhaust bezels makes sense to me with a rear-end repair. Pretty obvious that they masked around the exhaust bezles and then sprayed away since all of the rear bumper bolt heads were covered in black paint. The lower rear valance is a GM service replacement, along with blue GM service stickers on rear bumper braces, valance support rods, the tank support was bent and reinstalled, spare tire tub and lid are GM service replacements with blue stickers on them.

What has me puzzled is finding the very same colored primer under the front side markers and under the front chrome hockey sticks? Front lower valance appears to me to be original but I can't make sense of the primer? I will eventually have the car repainted but that is a year or two down the road.

I'm open to any and all opinions. I know just enough to be dangerous so don't worry about hurting my feelings. My first restoration. I'm a novice who is learning as I go.

[Leif A.]

Re: Paint and primer question - 1969 Tuxedo Black

Kevin,
You're in for a fun journey...all the best with your restoration. Out of curiosity, what is the paint code on your trim tag? Also, what was the exterior color name on the tank sticker that you were fortunate enough to retrieve?

[Jon H.]

Re: Paint and primer question - 1969 Tuxedo Black

Can you post a picture of the trim tag?

[Kevin S.]

Re: Paint and primer question - 1969 Tuxedo Black

Hello Leif,
The trim tag code is 900 Tuxedo Black.

The gas tank is a GM service replacement tank (not the original gas tank) with a large white sticker with blue print stating where the tank was shipped to and then the name and address of the Chevy dealership in Milwaukee, Wisconsin. There is no paint code information on this replacement tank sticker.

Label information printed in blue says,
GM General Motors Parts Division
General Motors Corporation
Chicago Parts Distribution Center
2600 South 25th Avenue
Broadview, Illinois 60153

The GM information is located in the top left portion of the label and the name of the dealership is located in the bottom center of the label in larger print. I preserved the GM replacement tank sticker by putting a piece of mylar plastic over the label and then packing tape around all four sides to prevent any further damage. The label is in great shape considering the age. Too bad it was not the original tank sticker with all the car's details on it.

[Kevin S.]

Re: Paint and primer question - 1969 Tuxedo Black

Hello Jon,
Certainly, here is the trim tag.

One of the many mysteries regarding this car is the primer color, which is white with a blueish green tint to it. Not sure what I was expecting. I am no paint expert but I would have thought a black car would have had a primer color like red oxide or something along those lines. Was surprised to see white.

I had a professional painter come out to my house to evaluate the paint and the car and he was puzzled too. Said we would not know all the details about the paint, the past repairs, etc. until we get the car stripped down.

[Owen L.]

Re: Paint and primer question - 1969 Tuxedo Black

I don't think you can put much stock in the front and rear primer colors. Both ends of the car are subject to altercations with the outside world from speed bumps, curbs, parking mishaps, etc. While the car was repaired and repainted from the rear collision, they might have just asked for a touch-up of the front chin area to fix curb rash or some other wear and tear.

You also stated that you believed the car to have been repainted once, so wouldn't that alone account for the matching primer? (Maybe I missed the mysterious part.)

On a side note does anyone have knowledge about what primer colors were used for which exterior color? My Targa Blue '72 seems to have a gray primer visible in various places where the original paint has been abraded or just plain worn through, whereas, my Elkhart Blue '67 had red primer.

[Mark F.]

Re: Paint and primer question - 1969 Tuxedo Black

Kevin,

This is the paint process described for 1967 (and probably all C2s) from the GM Model Specifications Book with some highlights about primers I put in there
I know your is a '69, but I doubt the paint process changed all that much.
kinda hard to read, so I added the text below the image


C2 Paint Process from 1967 Model Speccifications.jpg

1. PRIMARY SANDING. All body panels and bonded joints that receive acrylic lacquer are dry sanded to prepare surfaces for painting. A filler material, called putty rub, is applied to the entire body to fill minor imperfections.

2. PRIMER. Two coats of primer are applied -- the first red and the second gray -- and are oven baked for 60 minutes at 280 degrees F.

3. WET SANDING. The body is wet sanded to provide a smooth surface for the sealers. Most of the gray primer coat is removed with the red primer acting as a depth signal for the sanding operation. The body is dried to remove all moisture.

4. SEALER. One coat of sealer and one coat of color acrylic lacquer are applied and baked.

5. DRY SANDING. The body is dry sanded to prepare surfaces for the final acrylic lacquer.

6. LACQUERING. Three coats of acrylic lacquer are sprayed on the body to build up the required paint thickness. The paint is "rested' for eight minutes to permit It to partially set up and to remove excess volatile paint vehicle.

7. INITIAL BAKING. The body is oven baked for 30 minutes at 140 degrees F to harden the paint which permits the subsequent operation. Small interior and exterior parts are painted to complete the body paint schedule.

8. FINAL BAKING. To assure a durable, hard, high luster finish the lacquer is oven baked for 45 minutes at 250 degrees F. Reheating the lacquer permits the paint film to soften and allows surface blemishes and sanding scratches to disappear during the thermo-reflow process.

9. FINAL SANDING AND POLISHING. The body Is lightly oil sanded and polished to bring painted surfaces to a high luster finish.

[Mark E.]

Re: Paint and primer question - 1969 Tuxedo Black

I agree with Owen- no real mystery here. When spraying a car complete, its common practice to primer and/or seal the entire car. Is the original paint under this, or does it look like they stripped it?

[Kevin S.]

Re: Paint and primer question - 1969 Tuxedo Black

Hey Mark,
There are areas like under the door sill plates where you can see what I believe is the original black paint. Pretty crappy repaint job, looks like they were in a hurry and not very careful masking. Ugh!

Given one repaint related to the rear end damage, perhaps they just primed and repainted the entire car? That could expain the unusal primer color under the front marker lights and under the front chrome hockey sticks.

[Mark F.]

Re: Paint and primer question - 1969 Tuxedo Black

Kevin,

Look at the inside of the floor pan close to the outside of the car (example: lift the carpet adjacent to the sill plate, or behind the B-pillar) and you should see what the factory primer(s) were.

The "repainters" may have used white as a guide coat for when they sanded the black top coats. White underneath would show up high spots better than primer red - although it would also show up more with nicks and chips

Odd choice indeed...

[Kevin S.]

Re: Paint and primer question - 1969 Tuxedo Black

Hi Mark,
This was really helpful. I printed the exterior paint process steps off and will keep it for future priming and painting down the road. Thanks!

Any idea where I might locate the Exterior Paint Process steps for 1968-1969. GM Service Manual? NCRS book? The car's build date is Oct. 31, 1968. I assume the process steps are the same from 1967 to 1969 but it would be nice to know for sure.

[Kevin S.]

Re: Paint and primer question - 1969 Tuxedo Black

Hi Owen,
Yep, that make sense to me too. It would, could explain the differences in the primer colors used under the exhause tip chrome bezels versus the primer color used under the front marker lights and under the front chrome hockey sticks.

Guess the only way we will ever figure all of this out for sure is once we strip and repaint the car. That should also reveal the two (red+gray) primer steps that Mark included in his reply regarding the Exterior Paint Process.

[Mark F.]

Re: Paint and primer question - 1969 Tuxedo Black

Hi Mark, This was really helpful. I printed the exterior paint process steps off and will keep it for future priming and painting down the road. Thanks! You're Welcome !

Any idea where I might locate the Exterior Paint Process steps for 1968-1969. Yes - see link below from the GM Heritage Center GM Service Manual? NCRS book? The car's build date is Oct. 31, 1968. I assume the process steps are the same from 1967 to 1969 Yes, they were but it would be nice to know for sure.

Hi Kevin,

Your car should have been mine ! My birthday is October 31st (not 1968, though)...Mummy used to say she didn't know if I was a trick or a treat

page 113 in the document linked below shows the same steps I sent you before...
Plus there is a ton of other useful info in these "Vehicle Kits" GM has assembled...
Hope this helps...

https://www.gm.com/content/dam/company/no_search/heritage-archive-docs/vehicle-information-kits/chevrolet/1969-Chevrolet-Corvette.pdf

and this is the link to the Kit home page if you have other vintage GM cars...

https://www.gm.com/heritage/archive/vehicle-information-kits

[Leif A.]

Re: Paint and primer question - 1969 Tuxedo Black

What's curious to me is when the car was repainted, it appears by the color of the primer under the side marker lights and under the exhaust bezels, that they removed the side lights, exhaust bezels and everything else to prime the car. Why would they, then, install the side lights, exhaust bezels, etc in order to have to mask them off to apply color. Something just doesn't jive here. Final assembly of all the chrome bits would have taken place after final color, clear, sanding and polishing.

[Mark F.]

Re: Paint and primer question - 1969 Tuxedo Black

Leif,
I agree - goofy indeed.

Is it possible then that the white is not primer ?

...As in somebody painted the car white - and either the person who painted it white didn't like it (or a later owner) - and then it was painted black w/o chrome pieces being removed ?