A jobber can be the key to a smooth transition to waterborne paint work
Shop owners and managers also are likely to have concerns that any change, especially one as imposing as changing a paint system, can cause a loss in productivity during the transition period. Paint manufacturers and their representative jobbers know this, and most have made arrangements to support shops during this time. It is in the best interest of both the manufacturer and the jobber to help make the move to water as smooth as possible — both for the shops and for the jobber's revenue stream.
So how will a shop know that a jobber is prepared to help them switch to waterborne basecoat? Shops should make sure that the jobber can do all that is necessary by looking at the jobber's resources. Ask the following questions:
- Are the company's storage and transportation capabilities adequate to meet the needs of waterborne?
- Has their staff been trained to know the system thoroughly so they can answer our questions?
- Will they inspect my shop to see what equipment, tool, and storage changes, if any, must be made prior to installing a waterborne system?
- How much training is available for the shop's painters before the transition?
- Can they be contacted quickly for phone advice or on-site help? How much time are they willing to spend in our shop as the transition takes place?
Because different regions of the country have different requirements, the jobber should be trained by the paint manufacturer to help with these requirements. What else should you expect from your jobber and what help should expect? Read on.
Evaluating your shop
The well-trained and prepared jobber will come to your shop with a checklist of items to evaluate, including things such as: airflow in your booth, whether amounts of compressed air are sufficient, "correct" spray guns, gun cleaning equipment, storage and waste. If you do not have the needed equipment, they should be able to supply you with available types and potential venders to choose from. There is a staggering array of types and pricing for air-movement equipment alone, some more efficient than others. And just because the equipment is elaborate does not necessarily mean that it is the best choice for your shop.Air flow
The jobber should check your present spray booth to see if any air movement amplification is needed. Most paint manufacturers recommend 100 to 125 cfm as needed to evaporate waterborne paint. A velometer measures the booth's air movement. To determine that the booth produces enough air movement when parts are edged in, measurements need to be taken with the booth loaded with a vehicle and then with parts. Also, the measurements need to be taken in several locations in the booth to determine if there are "dead" spots, areas that may not have sufficient air movement to evaporate waterborne paint.Several different types of air amplifiers are available that can be used in existing booths. Some are expensive corner venturies that can be programmed to operate while waterborne basecoat is being sprayed but not when solvent clears are being used. (Air amplification should not be used with solvent clear application to keep dirt to a minimum.) Other types of air amplification are simple fans in the ceiling of a booth.
The least-expensive type is a venturi-style amplifier. These can be hand-held or used in combination on a stand (a tree). What makes this type of air amplification most practical is its versatility. The venturies can be "aimed" to direct an air stream past the parts being painted and at the level that would be most efficient. Air should pass by the part that is flashing off the moisture. If blown directly at the part, it will dry more slowly. Additionally, if the air is blown past the part, dirt is less likely to be driven into the painted surface. Mobile air-amplifying trees can be removed to another booth or to parts that are being edged in, while the clear is being applied and cured. Your jobber can explain the advantages and disadvantages of air movement equipment so you can make a knowledgeable decision for your specific needs.
In some circles there is a debate over whether crossdraft spray booths will evaporate waterborne coatings faster than downdraft booths. Consider that many shops have converted to downdraft booths in the past 15 years, and these booths are still the best for application and curing of solvent-borne clears. A moveable venturi tree with sufficient air volume becomes a very practical and economical investment.
Compressed air
When HVLP spray guns were introduced and larger volumes of air became necessary to operate these guns, air consumption went up. Body shops became aware of the value of air volume for good results. With an HVLP gun requiring 10 to 15 cfm and each venturi air amplifier requiring 13 to 15 cfm, a painter's requirement might be as much as 60 cfm just to paint and dry one vehicle. To produce these volumes of air, the air supply lines need to be 1.5 inches in diameter to move the amount of air. As the need for air volume goes up, screw compressors become more practical to supply it. Quick change couplers also become critical. Larger volume inlet couplers, though they connect to the same 31/48-inch hose, allow for the larger volume of air that is needed to run this equipment.
Air that is both clean and dry is also critical. Your jobber can test your existing air supply for both with a dirt particle filter. Clean test paper is placed in the test device. Then the booth's air is passed through, after which it is examined for dirt or oil.
The compressed air humidity and temperature should also be tested to determine if the air dryer is operating sufficiently and to assure that the air is not too hot or cold. Your jobber can inspect and test your existing equipment to assess if it will meet the needs for a successful transition to waterborne.
Spray guns
You may be able to retrofit your existing gun to spray waterborne coatings, and with precise care you can use one gun to spray both waterborne coatings and solvent clears. Both of these practices are difficult. Preferably, a dedicated spray gun that is designed to spray waterborne should be used.
Depending on your paint manufacturer, the tip size may vary from a 1.25 to a 1.3. The internal parts of a water gun are stainless steel to avoid rusting. Air pressures may be different with waterborne coatings, with some companies recommending a higher pressure for the first two coats (34 pounds recommended by some), and then one to two control coats at a lower pressure, such as 14 pounds. Due to this variation, precise air pressure control at the gun becomes both critical and convenient for application.
Gun cleaning
Waterborne spray guns cannot be cleaned in the same gun cleaner as solvent guns. The two waste streams cannot be commingled either. Gun cleaners have been developed to clean waterborne guns. A simple rinse in water is not sufficient to do this job. Special cleaning water is recommended by most paint manufacturers. This water is demineralized and deionized and contains additives. As with reducing water, minerals in this water too can change the color of a finish. Some older publications use to recommend that a gun be rinsed with alcohol following a water wash. This alcohol rinse would purge the gun of water, which otherwise could caused rust in non-stainless guns. The use of dedicated guns makes this unnecessary. A blast of dry air through the gun following cleaning is sufficient.
The water in most gun cleaners is more than tap water and can be reused for a fairly long time when a "flocculating" agent is used. In this procedure (to be performed during the evening), as the cleaning water becomes saturated with latex residue, a special powder is added, and a slow stirring paddle is started. The flocculating agent causes the latex particles to bind together. In the morning these particles can easily be strained out using an instrument that looks like a large coffee filter. The remaining water can be used up to 10 times.
Your jobber can explain the different equipment options, demonstrate how they are used and know local requirements that may be relative to installation and operation. A jobber also would know who is licensed and available for waterborne waste removal in your local area.
Storage
One significant difference between waterborne and solvent coatings is storage temperature. Waterborne paints should be stored in an area that does not drop below 46 degrees F or above 75 degrees F. Many shops likely will be not be able to easily maintain this 29-degree storage temperature range. Although each paint manufacturer has different temperature ranges, your jobber, who needs to maintain these same storage criteria, will be able to advise you regarding a brand's specific requirements. In very cold and hot conditions, care must be taken throughout manufacturing, shipping, warehousing and end use.
Some publications have noted concerns about waterborne shelf life. With most paint manufacturers, though, paint toners have a shelf life of from 24 to 48 months, which should not be a concern for most shops. Your jobber will help you know how to find the manufacture date on the product and will advise you regarding your brand's specific shelf life.
Depending on the brand, you may need an agitating mixing bank as you would with solvent toners. Your jobber will be able to provide the necessary training and advice regarding the mixing equipment needed.
Training
Training of painters at manufacturer's schools for both classroom and hands-on preparation training is critical — in addition to the training that the jobber provides as a shop transitions to waterborne products. Though the differences with preparation and application are not great, sending painters to a school where they can practice application in an environment that is not schedule-driven will allow them to become fully confident about the preparation differences.
Waterborne preparation recommendations may differ from those for your present solvent-borne paint. Most paint manufacturers recommend a P800 to P1000 grit preparation for waterborne basecoat. Film thickness application may also vary from brand to brand, with one having a 1 to 1.5 dry film thickness and others having only .5 to .7 mils required. These differences only reinforce the point that prep and application training is vital.
Gun techniques also are different with most waterborne coatings, with a 75 percent to 80 percent overlap and gun distances varying from initial coats to the subsequent control coat or coats. One paint manufacturer recommends that two initial coats be applied at a spray pressure of 34 psi, at a distance of 8 to 9 inches, followed by one to two control coats at 14 psi and a 12-inch distance. The control coat is used to properly orientate the metallic and pearls. Meanwhile, other companies recommend a first "hairspray" (light) coat, then a closed coat (medium wet), followed by a control/cover coat. These variances reinforce the fact that specific manufacturer training and practice should be taken before changing over.
Though this may seem daunting, experienced painters — with training and support — can make these changes in a short time with a little practice. Most jobbers help by sending trainers to the shop as the transition to waterborne is made. With this help, painters can ask specific questions as they arise and incorporate the new techniques into their shop.
Final word: A profitable partnership
Change can be difficult, and having to learn new work practices is often met with resistance. But with the help of a well-trained jobber who knows the product well, the transition to a waterborne system can be completed with little interruption to the business, while helping a technician build confidence in the new system. Your jobber should be a valued helper as you transition to a waterborne system. n