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Sat Feb 07, 2015 3:14 pm

Can paint stores match the color on a car. I've got a 71 yellow ghia vert that the paint got scratched off in a few places. I don't think it's a OG color so matching by code probably won't work, also fading,oxidation and such. Don't really want to have to paint the whole car.
thank's for your imput.

Mon Feb 09, 2015 8:40 am

Quick answer, Yes.
Here is the issue: You'll need to provide a sample to match from. Typically something like the gas door.
But depending on the location of the gas door, it may be more/less faded, oxidazed than the color you want, so it may not be as simple as it seems. You may have to leave the car itself as a sample. For this, you'll need a painter, not just a paint store.

Mon Feb 09, 2015 10:59 am

I match colors for a living across a wide range of industries....not automotive...but I know for fact that serious auto paint jobbers use roughly the same equipment I do...because the people who make the equipment serve the auto industry as well.

yes....a long skilled painter can "generally" match colors....but I quite trusting eyeballs many years ago because the parts and items I match colors for cost far more than any paint job on any vehicle.

Modern paint houses use handheld spectro-densitometers (some have bench top console models as well). They may have names on the side like DuPont or PPG...but the units are all made by companies like Gretag-McBeth or Xrite (which now owns Gretag).

The problem with color matching by eye and experience is that it has no way whatsoever to account for density...which is how deep the paint is applied (not all paints are opaque which is why that matters).....pigment size and reflectivity ...which is critical in a metallic or large pigment paint like reds and oranges...and somewhat critical in paints that use red and orange pigments within their mix.

Any paint or coating that uses more than three toner pigments, or has a high percentage of white blender/base...much over 25%....or has a large percentage of clear as part of the mix (which spaces out pigments and magnifies reflectivity of the colors of all of the pigments).....will be prone to metamerism.

A metamerism is a color change/shift under various lighting conditions.

This is the biggest problem in eyeballing paints. Grays, beige's, and greens are most prone to this but with the right range of ingredients ...all can be prone to this.

This is why a spectro-densitometer is used. It has its own full spectrum modulated light source and reads color, hue, tolerance and density in one shot...are phenominally accurate...and used worldwide by all in the color field.
They read color in all known color systems and spheres from CIE to LaB to RAL and everything in between....to an average accuracy of about 0.2 Δe. The human eye cannot discern differences below 3-4Δe….and a metamerism error from eyeball color matching typically runs from 7-15Δe.

As air cooled head noted.....find a spot that is not sun faded or filthy...that has about 8" of all around room of access. A good paint jobber should have a hand held spectro unit. They will take 2-3 readings of your paint.

This is then downloaded to their paint scale. Their laptop or desktop should have the color coordinates of all of their toners and bases built in. They get this software for free from the paint manufacturers.
In about 2 seconds...it will crank out a mix recipe by weight for your color.

They will then mix a wet sample...and this is where a painter comes in....spray you a wet sample ...and then YOU and the PAINT JOBBER...will inspect this color in A table top LIGHTED COLOR BOOTH....usually three light sources.....6500k daylight....5000k and cool white fluorescent.

If they are smart...and you ask to see the color in sunlight....they should slap you twice.
Sunlight changes every minute of the day in every location. If your paint turns out to have a metamerism...they will NEVER be able to warrant the color no matter how its applied.

What they can do is go into the computer, look at the ingredients...and select a near shade that has less of one pain in the but ingredient or another.

There are literally thousands of shops that work in this manner. In this day and age...dont settle for uncle Joes shop just because an old timers experience would seem cheaper. If you live near any town of size you should be able to find a modern paint jobber. Ray

Mon Feb 09, 2015 3:08 pm

I'm probably going to paint it myself. Had good luck doing the engine cover on my bug years ago, and that was chromasystem 2 stage. The biggest spot is the engine cover(about 3 inch circle) so I'd do the entire thing. hardest spot I think to match will be the rear fender, It's got a strip about 12" or so long at the wheel opening, other spot is in the recess between the tail light and engine cover. maybe I can post pics.

Mon Feb 09, 2015 3:52 pm

Wow! Thanks for the edu, Ray. I had a Bug with a metamerism: Bubble-gum hot pink in daylight, kinda puple-ish under street lights, and violet under sodium-vapor lights. I thought is was cool; had no idea it was a mistake. :?

OP, those spots you mention are likely to have differing amounts of fade, oxidation. Make sure you take it to a painter, not a paint shop.

I took the gas door of my Squareback to a paint store, and they color matched it perfectly. Unfortunately, due to fading/oxidation, I couldn't use that paint on other spots of the car. :cry:

Wed Feb 11, 2015 11:30 pm

Make no mistake......there are interprising people out there who onow color...and metallics...and clear coats.....that design colors/paints to do this. I saw a low rider in Dallas years ago that used a, crazy metallic mix.....really destined to change colors in any lihht wource.
The painter....really an artist.....layered in on in very thin layers with a layer of clear between each one....about 8 layers. Its the equivalent of mixing glitter into molten glass. It looked a mile deep.....and each metallic in the origina mix reflected a different color under differnt light and from every angle. A gorgeous way to use the normally undezired effect in his favor.
Maybe you got an "engineered" color. Ray