When trying to create a first-rate color match, it's important to follow certain procedures and conduct proper tests prior to starting the paint job.
September 2000Returning a car to a customer with mismatched panels is just like leaving your house wearing two different socks: It's embarrassing, and when you finally realize your mistake, you hope no one else has noticed. But sometimes, you become aware of the problem a bit too late. With a car, you may not notice the mismatched panels until the refinishing and detailing are already done--and the customer already is on his or her way to pick up the car.How can you ensure a proper color match so a scenario like this doesn't happen? Through a culmination of several factors, including knowing how to create a high-quality color match.Check Before You Spray
Checking the color of both the paint in the spray gun and the paint on the vehicle before you spray is the most important factor in getting the color right the first time, says Phil Matisak, manager of color marketing for Sherwin-Williams. Once the color has been checked, you can develop a game plan--re-mixing, blending, tinting, etc.--for dealing with a color that doesn't match.Tools such as color chips, charts and manuals can be a painter's most valuable assets in color matching. "Millions of dollars are spent on the production of these items, and they should be treated as expensive pieces of equipment," Matisak says. This means keeping the information as clean--away from paint spills--and as up-to-date as possible. "Many of the shops that complain about color-match problems many times do not have the latest information, chips, microfiche or alternate fan decks," he says.What's more, though, is being knowledgeable enough about how to actually take advantage of these resources. Everyone in the paint shop needs to have a thorough understanding of all the color information because mistakes made at this level can prove costly. Not fully understanding how to use these tools has caused many painters to unnecessarily mix the wrong color and that means "more waste and more time spent mixing," Matisak says.To help protect against this, preparing and maintaining a library of popular colors is essential. These are the some of the easiest pieces of information to gather, and the library itself is worth its weight in gold, he says. Spray-out cards and binders are readily available from your paint supplier.When using these, make sure you use them correctly. Spray-out cards should be sprayed exactly the same way the car is painted: Spray gun distance, air pressure and the number of coats all play a role in the final appearance. "A card taped to the end of a mixing stick and sprayed while walking around the paint shop is not the proper way," Matisak says. The spray card also needs to be filled out properly. On the reverse side is a place for the painter to list valuable information about the color. Taking the time to catalog this information will save time and stress the next time the color comes around. "Several dollars are often wasted because some painters do not take the time to check a color before spraying," Matisak says.A Test Run
Before the actual refinishing process begins, doing a practice run of it on a test panel will make everything go more smoothly, says Jason Bartanen, a technical instructor and writer for the I-CAR Technical Center in Appleton, Wis. He says the most important part of achieving a correct color match is preparing a test panel. A test panel helps painters work out problems ahead of time, making the job faster and improving its quality. "I don't think this is done enough," Bartanen says. "That's where mismatches begin."When a test panel is made, it's essential that this is done correctly. The refinisher must use the correct primer, the same number of coats and the same spray techniques he or she plans to use when spraying the vehicle. For example, if a technician plans to use black primer but sprays the test panel with gray, the color could come out completely different on the car than it does on the test panel, depending on how translucent it is. "If you only use two coats of paint on the test panel when you plan to use three on the car, you can have a mismatch right there," Bartanen says. "The undercoat selection is important, especially with translucent colors, because you will see more of the primer underneath."Once completed, the test panel should be compared to discarded body panels or to areas adjacent to the repair area. This must be done in daylight or in daylight-corrected lighting.The time to identify a mismatch is not when the car is in the spray booth. Spraying the test panels can be done when the vehicle arrives at the repair facility, during the repair process or when the replacement parts are being edged. If a mismatch is noted, it doesn't necessarily mean that tinting is needed.There are several other factors that can affect color match. At this point, a refinisher must determine the following: if the paint code was properly identified; if the paint formula was followed correctly; if the paint was reduced properly; if the undercoat color is correct; if the test panel was made properly; if the test panel was checked against a clean vehicle; if the test panel was checked in the proper light; if the test panel was checked from both head on and side tone; if the test panel was checked in the area of the vehicle where refinishing will take place.Problems with Painting
Finding the correct color formula and developing a good match is difficult enough. But when you factor in some major paint problems and challenges--flip and flop and metamerism--the refinishing process becomes even more challenging. Flip, when a color matches at one viewing angle and mismatches at another, is not quite as severe as flop. This is when the paint mismatches at one viewing angle and mismatches in an opposite direction at another viewing angle. A case of severe flip and flop is a color that has a flip that is too red and a flop that is too green. The flip situation may be easy to fix. Many times it results from variation in metallic and pearl control. The arrangement of the flakes in the paint film--how they lay--can affect how the color travels, or flops. A change in solvent, to a different temperature range if available, will often fix the problem.Dark flops result from increased flake control, and more flake control is caused by a dryer spray application, which can be caused by the outcome of a solvent that is too fast for the condition or from low fluid deliveries. A light flop is the outcome of poor flake control, which tends to occur when a spray application is too wet. If application is the problem, a dark flop may be lightened by adding a flop-adjuster of white or white pearl, says John S. Ceglarek, manager of color technology for Sherwin-Williams.On the contrary, a flop that is too light typically means one of two things: The formula contains flop adjuster and does not need it, or it contains too much of an opaque pigment, such as white. In either case, a remix is necessary and removing components from the color formula could lead to a worse match, Ceglarek says.The more severe a flip/flop problem is, the greater the likelihood is that the wrong pigmentation was used. "These types of pigment problems are not usually solved easily and should be left to experienced color matchers," Ceglarek says.Metamerism, a condition that occurs when two colors match in one lighting condition and mismatch in another, generally results from trying to match a leaded paint formula with unleaded pigments or vice versa. "For this reason, it is mostly confined to the yellow and orange color families, which are almost exclusively solid colors," Ceglarek says. "Metamerism is virtually non-existent in metallic and pearl colors because it is rare to get even close to a color match with anything but similar pigmentation." If a color match ends up being metameric, the best option is to look for an alternate formula because it is impossible, in most cases, to correct the problem by tinting the formula.To prevent such problems, take advantage of technical training offered by I-CAR, the paint manufacturers and other companies. Johnston also suggests partnering with your suppliers to obtain their services and technical expertise and to consult trade publications and the Internet for additional information.The Right Light
When it comes to lighting, three components contribute to how a color is viewed--the first is light itself, and the other two are the object and the observer. In this case, the paint is the object, and you are the observer. "All of these components are equally important when viewing color, and therefore, need to be taken seriously," Ceglarek says. This can be challenging because several very different lighting conditions are found in a typical body shop environment. The majority of shops use some type of fluorescent tube lighting in the mixing and shop areas, as well as in the spray booth itself. Some shops also use incandescent light in the spray booth, which makes yellows, oranges and reds appear predominant, while violets and blues are more subdued. In addition, any color viewed under incandescent lighting looks slightly redder than it really is.Sunlight is the best light in which to view a vehicle because it reflects all of the available visible wavelengths of light, enabling colors to be viewed in their truest forms. Because cars are outside most of the time, it's essential to have daylight-type lighting throughout the shop and in the spray booth. The Color Rendering Index (CRI), a measure of light quality, uses a scale of 0-100 to rate a light source. The higher the CRI, the truer an object's color will appear. Natural, unobstructed daylight scores a 100 rating, while most fluorescent lights range from 70 to 85. "Fluorescent lighting will exaggerate some color mismatches and minimize others relative to daylight," Ceglarek says.Although it's best to view a color match outside in natural light, it's also acceptable to check the color inside under daylight-corrected lighting. Strategically installing a skylight can significantly help to judge whether a color match is good enough to be used on a vehicle because it allows daylight into the shop."Using proper lighting can help protect against a great deal of unnecessary tinting as well as surprises that [may] occur when the color matches in the spray booth but not in the lot before it is delivered," Ceglarek says. Taking these precautions, he says, "saves time, material and money."The ideal course of action is to install daylight-corrected fluorescent lamps in the mixing and spray booth areas. But Ceglarek warns that these lamps only reduce the problems found with the more common fluorescent lamps. With fluorescent daylight, blues, yellows and reds are seen much more readily, but blue is the most dominant color by far. Colors may also appear to have a slightly greenish-blue cast. This is why it's still essential to scrutinize the match even when a shop uses daylight-corrected lamps.Separate, Sorted and Blended
When developing a color match, it's important to tint the paint only with the colorants in the particular formula you are working with. For example, do not just take a red off a machine. Apply the same rule when working with toner. If you determine a color isn't a perfect match, you may add toner. But if you use a different toner than what is in the original pigment, it may not match under different light."A conscientious painter will only adjust color with the toners that already exist within the color recipe," says Tom Tarrant, color manager for DuPont Performance Coatings. "Take time to figure out what's in the paint."You should also check color movement after each tint addition, and keep a record of each tint used and the amount added, says Art Allred, training director of Valspar Refinish. He also advises against tinting all of your mix. But if you must, do so only as a last resort.Properly agitating tints before mixing and agitating them on a regular basis also helps to develop a good color match, Tarrant says. Doing so ensures the tints are not thrown out of balance. "Pigment could settle and binder could just come out," he says. "Then you would just have pigment, and it would be much stronger. Although you might have a good mix, if it's not properly agitated, it could become a bad mix."Tarrant also advises against skipping steps. "Sometimes steps are sacrificed or not done as completely as possible," he says. This is the beginning of a bad habit that will cost a refinisher time and money, he says. If a painter does not wash the car properly with soap and water and then use a pre-cleaning solvent to eliminate non-water based contaminants, such as wax, there is a good chance problems will arise. "Proper preparation is critical," he says.Even if you follow these steps, the area of the car that is painted may still not match unless you blend the color into adjacent panels. This may seem insignificant to refinishers who already know the importance of blending, but it's important to make the reminder. "Most shops do blend on a regular basis," Tarrant says. "But there are still a lot of shops that say, 'I don't get paid to blend.' [These shops] then risk a customer noticing and may possibly have to repaint [the car]. The human eye is sensitive to color shifting, especially with metallics or pearl."However, blending will only take care of a minor mismatch, says I-CAR's Bartanen. "It only hides slight variations," he says. "It won't cover up any major mistakes." Nonetheless, it has to be done. "You can't panel paint anymore," Bartanen says, "even if you think you have a perfect color match."Johnston agrees, adding that he thinks the most important issue when it comes to color matching is, in fact, color blending. "When color variations are to be expected or where there is no limit to the areas to be sprayed, it is better to use the blend technique of spraying into the surrounding area," he says.By checking your spray gun for contamination, creating a test panel and using proper lighting, you can help ensure that you've created a good color match that will lead to more satisfied customers and fewer comebacks. You'll also be spared the embarrassment of having a mismatched vehicle. Now all you have to do is check your socks.Blending: is the process of allowing some of the original finish to show through the refinish coating; reduces the visible difference between the original and refinish areas; tricks the eye into seeing only one color.When properly done, blending can help disguise slight differences in colors. Blending is performed on most refinish repairs, when the technician is not able to hide a severe color mismatch, and is done after tinting on as small an area as possible.There are scuffing compounds available for the following: preparing areas for blending; areas where a DA sander cannot adequately access, such as inverted curved areas; use as a "final sand" to ensure no areas were missed in the earlier preparation stages.Source: I-CAR "Finish Matching" Student ManualSpraying TechniquesDarkerHold gun closer to the jobDecrease gun speedDon't wait as long between coatsUse larger fluid tipDecrease fan widthDecrease air pressureIncrease volume of material flowDecrease shop temperatureLighterHold gun farther from the jobIncrease gun speedWait longer between coatsUse smaller fluid tipIncrease fan widthIncrease air pressureDecrease volume of material flowIncrease shop temperature20 Solutions to Color Matching ProblemsSeventy percent of a color matching problem is theorizing and discovering the answers, 20 percent is figuring out how much toner needs to be added to the mixed paint and 10 percent is knowing how to blend, says Eric Ashman, Akzo Nobel's technical manager for technical services. "There's no such thing as a perfect color match," he says.When battling a less-than-acceptable match, the first step is to remember that cars only come in four colors--red, yellow, green and blue--with the exception of the neutral colors, such as blue, gray and black, Ashman says. Brown and orange fall within the category of red, and violet falls under the blue category. Knowing this means you already have the knowledge needed to solve virtually any color-matching problem, he says.The next step is to ask yourself why the spray-out doesn't match the car. Ashman offers the following solutions:RedIf you're working with a red car and the spray-out doesn't match the car's paint, it's because of the following: The red car is redder than the spray-out. The car is redder, slightly more yellow than the spray-out. The car is redder, slightly bluer than the spray-out. The car is more yellow than the spray-out--a more extreme case. The car is bluer than the spray-out--a more extreme case. GreenIf you're working with a green car and the spray-out doesn't match the car's paint, it's because of the following: The car is greener the spray-out. Add green paint to the spraygun. The car is greener, slightly more yellow. The car is greener, slightly bluer. The car is more yellow--a more extreme case. The car is bluer. The only thing you can put in the paint to make it match at this point is blue--a more extreme case. YellowIf you're working with a yellow car and the spray-out doesn't match the car's paint, it's because of the following: The car is more yellow than the spray-out. The car is more yellow, slightly greener than the spray-out. The car is yellower, slightly redder. The car is greener than the spray-out--a more extreme case.The car is redder than the spray-out--a more extreme case. Blue The car is bluer than the spray-out. The car is bluer, slightly greener. The car is bluer, slightly redder. The car is greener--a more extreme case. The car is redder--a more extreme case.When it comes to neutral paint colors, such as gray or white, Ashman says there are a few more solutions to remember because these cars are a bit trickier."Gray cars and white cars most [technicians] find more difficult because they are harder to read," he says. For example, there are three colors involved with yellow, but with white, four colors can be spun off. "You have to decide on a color group, such as if a white has to go slightly redder," he says. "Then you have to dig a bit deeper into the color group. You can't just pick any old red. You can talk about all the fancy lights, but [the painter] still has to have this basic knowledge."The painter must also ask the following questions when refinishing neutral-colored cars: Is the color of the car redder than the spray-out? Is it yellower? Is it greener? Is it bluer?"You have to coordinate colors in your mind," Ashman says. "That's how you come up with solutions to color problems."Source: I-CAR “Finish Matching” Student ManualHow to Color Match EffectivelyBASF Automotive Refinishing suggests that painters follow these steps for effective and correct color matching:Step One: Checking the Color Check the color in the can. Use the recommended reduction and air pressure. Spray color on a test panel. Clear basecoat colors before checking color. Let the color dry before checking.Step Two: Comparing the Sprayed Color with the Original Clean the surface to be matched. Use daylight to check the color. Determine if the original finish is lighter or darker. Determine if the original finish is more blue, green, red or yellow than the spray-out. Determine if the original finish is brighter or more graythan the spray-out. Check the face and the pitch of the original color for color match.Step Three: Adjusting the Color by Tinting Try the tinting bases used in the formula. Look in the color matching guide to determine which tinting bases to try first. Use one tinting base at a time. Use small amounts of the tinting bases. Spray the color after each adjustment. Ensure the color is dry before determining the true color. Clearcoat basecoat colors before determining the true color. Match on the light side of the color.Source: BASF Automotive RefinishingA color-effect test panel may be required for basecoats which contain mica. To make this panel, do the following:1. Apply a primer that is the same color that will be used on the vehicle. Allow to dry.2. Mask the panel into thirds, leaving one panel exposed.3. Apply one coat of basecoat to the exposed section. Allow to flash.4. Unmask the next section and apply another coat of basecoat. Allow to flash.5. Unmask the last section of panel and apply an additional two coats of basecoat to the entire panel. Allow to flash.6. Apply clear to the panel. Follow the paintmaker's recommendations. Allow to dry.7. Compare the test panel to the vehicle to determine the number of basecoats needed to provide the best match.Source: I-CAR "Finish Matching" Student ManualA test panel helps painters work out problems ahead of time. It's essential that this is done correctly. The refinisher must use the correct primer, the same number of coats and the same spray techniques he or she plans to use when spraying the vehicle.Source: BASF Automotive RefinishingIf you've followed all of the manufacturers' recommendations for matching the paint on the vehicle with the formulas in the computer and still can't seem to get a match, then it's time to look at alternative formulas for that color.At the factory, slight differences in the type of paint used, the spray procedures, and solventborne vs. waterborne formulas can alter a color from one vehicle to the next. The color position of a solventborne formula is darker than a waterborne formula, says Tom Tarrant, color manager for DuPont Performance Coatings. "It could be the same color, but it may have a different position in color space," he says.To combat this, manufacturers sponsor audits in which they send people out to look at cars as a group and develop alternative formulas. These offer additional options if the original formula just doesn't seem to match the original paint on the car.Some shops have also embraced the use of spectrophotometers. These tools are portable, very sensitive color instruments that look like a camera, use a combination of the spectral curve and mathematics, and have the paint formulas loaded into them. The picture is put into a database and then compared to stored formulas. If the scanned color doesn't match anything in the database, a new formula will be created based on what's scanned in.Color Matching through Technology: Sorting Out the ColorsBecause you can't always trust your eyes to accurately view a color, Albert Munsell's color theory, developed in the early 1900s is important. This led to the creation of a color wheel, which is used to show how colors are related. Munsell's theory is based on three characteristics.These three dimensions are used to position colors in a logical sequence on a color tree relative to each other. According to I-CAR's "Finishing Matching" manual, this system works well for solid colors. However, a slight change is required when working with metallics and micas because these types of colors were not developed when Munsell created the color tree.Here is an explanation of the three dimensions:Value--This is also commonly called lightness or darkness. Value typically is the ratio of white to other pigments. It must be identified first, and value typically increases when white is added. When other pigments are added, the value usually decreases. But there are some exceptions. For example, white added to some reds turns them pink.Hue--This is often referred to as color, cast or tint. Hue can only move in one of two directions around the color wheel. For example, blues can only move to the red or green side, and reds can move to the yellow or blue side. When evaluating hue, a refinisher needs to determine the direction the color has to move to obtain a blendable match.Chroma--This is also sometimes referred to as saturation, richness, intensity, muddiness, grayness or purity. Chroma is the level of intensity of a color, within a set value level. When using the color wheel, chroma increases as it moves outward from the center axis and decreases as it moves closer to the center axis.Source: I-CAR "Finish Matching"Student ManualHere is some step-by-step color matching advice from Gueary Preston, director of color and information systems for PPG: Make sure the toners are mixed two to three times per day. Make sure the formula is made to specifications. One overpour can destroy the color. Use one product line. Do not mix products from different companies. Watch the air pressure in the air line to the gun. Use the correct reducer for the product and temperature. Allow flash time. Use the correct mix ratio. Use the correct gun setup. Always be ready to blend.Color By Numbers: Avoiding the Halo EffectTo avoid the halo effect in the repair area when applying a multi-stage finish with a mid-coat, one paintmaker recommends this application method:1. Apply the first mid-coat to the area covered by the basecoat.2. Apply the second mid-coat well beyond the edge of the first coat.3. Extend the third mid-coat just beyond the edge of the first coat but within the second coat.4. Apply the fourth mid-coat to just beyond the edge of the second coat.Source: I-CAR "Finish Matching" Student ManualAlthough it's best to view a color match outside in natural light, it's also acceptable to check the color inside under daylight-corrected lighting. Strategically installing a skylight can significantly help to judge whether a color match is good enough to be used on a vehicle because it allows daylight into the shop.
