Advanced color matching

paint matches Al Thomas The first thing that the customer looks for when picking up a repaired vehicle is the color match. It simply doesn't matter to the customer that the vehicle arrived at the shop nearly totaled, that the complexities of the repair required the most skilled technician in the shop, that replacement parts were difficult to find or that repairing the vehicle on schedule as promised proved to be a challenge. It's always color match that customers judge first. Often, their opinion of the match guides the remainder of their satisfaction with the repair.

Color match also is most likely the first characteristic to be noticed because it can, and often is, first judged from a distance, as the customer approaches the repaired vehicle. If the color is "off," the hope for an "undetectable" repair is lost. I have heard customers say, "If they can't even get something as simple as the color match right, what kind of job have they done on the rest of the car? How hard could it be?"

As anyone who has ever blended paint knows, it's extremely hard. Creating the best possible paint match has gotten more difficult. With different factories producing different variations on a single color code, what was once the simple fact of retrieving the manufacturer's paint code, converting it to your paint system code, mixing the color and applying it, is no longer as simple as it once was.

What can a painter do to produce the best blendable match? There is not a single answer. A combination of actions must be performed correctly for the color result to be acceptable. Some of the more basic areas such as gun set-up, air pressure, spray technique, formula mixing, proper reduction, and spray environment (temperature, humidity and air movement) all affect the color. But if these areas are not being followed correctly, all colors will be off. Even a "corrupt rack" will affect those colors that have become compromised.

The techniques or systems that will help with those difficult colors include items such as spray-out panels, variant decks and correct color evaluation, along with computerized color match aids such as: spectrophotometer, VIN color retrieval, computerized spray-out panels, computerized tinted formulas and computerized formula pouring.

STEP 1: Spray-out panels

Creating spray-out panels, while not necessary on every color that is to be matched, can be very helpful on difficult colors or when the painter is not sure that the variant is correct. Though most formula systems today give prime color formula (the most likely color for that code) the known variants and the color of the undercoat for proper match, painters may still question whether the color will be a blendable match. To be sure, a spray-out panel should be performed. Most paint manufacturers will provide a card to which the mixed color can be applied. This card generally has the different sealer colors printed on it to confirm the correct undercoat. The painter must simulate the same reduction and spray techniques that will be used when the vehicle is painted. When coverage is achieved, the card is cleared (exactly as the vehicle will be) and then compared under correct light to the vehicle.

The advantage of a spray-out panel is that a formula's blendability can be verified prior to the paint being applied to the vehicle, which can save a considerable amount of time and expense. The disadvantage is that making a spray-out panel does take some time, though it may not be necessary for every color. Many painters will make a spray-out panel as the vehicle is being edged in, thus saving time.

STEP 2: Variant decks

Because a particular paint code mix may vary slightly for different manufacturing plants (due to different application equipment or even different systems – water, solvent or powder coat), vehicles often have slight variations in color. When a variation is noted, paint manufacturers will reformulate a color and publish it in its color variant deck. These formulas have labels such as "darker" or "lighter" or other descriptions to indicate how they are different from the original or prime.

The paint technician can take the paint variations and, using color corrected light, compare it to the vehicle being painted for the best blendable match. At this point, the painter can make the decision to either make a spray-out panel or, if confident that the color is a blendable match, can proceed with the chosen variant.

STEP 3: Correct color evaluation

There are some key points that painters must keep in mind as they evaluate their color choice. First, the correct type of light must be used to evaluate a vehicle: It must be color corrected or the same as sunlight – a color rendering index (CRI) of 85 to 92 percent to properly match the spray-out panel or the variant chip is necessary. Other types of light sources such as incandescent or standard florescent may appear to match, but when the vehicle is taken outside in sunlight it may not.

Next, the color comparison should be performed at different angles, such as straight on and at 45 degree angles to the right and left. The light source should be moved at different angles as well. Careful evaluation should be made to evaluate the color as compared to the vehicle.

Often there may be only fine differences between the color of the vehicle and the formula that has been mixed. Note that as you compare the two colors your eye may become fatigued. This color fatigue can happen after concentrating on the comparison for only a minute or less. Though you may not notice this fatigue at first, it makes it harder to evaluate the subtler differences in the colors. To combat eye fatigue, the painter needs to compare the colors for a minute or less, then look away for a few seconds, and then go back to check the comparison.

STEP 4: Computerized help

As with many other areas in our lives, the computer has become useful when matching the paint of a vehicle. A "camera" takes an electronic picture of the vehicle, and the Vehicle Identification Number (VIN) is keyed in. The computer compares the vehicle color to formulas and provides a blendable match. Some programs even have side-by-side images of the picture and the formula for comparison. The chosen amount is calculated for the repair and the tints are placed on the machine, which precisely pours the chosen formula.

Match aids include:

SPECTROPHOTOMETER Over the past few years, computerized matching aids have been developed and become more practical for the repair industry. The spectrophotometer, a "camera-like" machine that takes a picture of the vehicle being refinished then compares it to a large data base of formulas to choose the best one for that vehicle, has become more accurate and practical for use in shops. Though the exact procedure for each different device may vary, the general procedure is the same.

The device is first calibrated and a flat and clean area in the blend area is chosen and prepared for sampling. The sample area should be cleaned very well with detail clay or light polishing, then with a wax and grease remover and finally with a dry cloth. Note: The cleaner the sample area, the more accurate is the reading. Multiple readings are taken and stored in the device, which is then attached to the paint computer, where the sample is compared to the stored formulas to determine the one closest to the vehicle being painted.

VIN COLOR RETRIEVAL Computerized paint code retrieval by vehicle identification number (VIN) now is available on some manufacturers' systems, which has saved countless hours of searching for the manufacturer's paint code. The VIN is keyed into the system, which retrieves the formula. When used with a spectrophotometer, retrieving a match is more likely.

SPRAY-OUT PANELS With some electronic systems, an electronic spray-out panel is generated with the chosen formula, and the "picture" of the vehicle is produced for side-to-side comparison.

AMOUNT CALCULATORS Most systems now have amount calculators that help the technician decide just how much paint to mix for the repair. This is both a great time and cost saver. The panels to be painted and blended are keyed into the computer, which then provides the recommended amount.

FORMULA POURING Electronically controlled paint tint pouring systems are now available. They precisely pour each color to the exact amount called for in the formula, producing the exact color.

As paint colors become more complex and the task of producing an undetectable color match becomes more difficult, painters must adapt to the challenge by using all the tools at their disposal.