What Every Wisconsin Body Shop Needs to Know About Waterborne Automotive Paints
A Primer On The New Automotive Paint
For a lot of body shops and “old school” painters, waterborne paint technology is viewed as a newfangled technology. Actually, waterborne paints were first introduced in Europe in the early 1990s after 20 years of development by some of the leading paint companies.
Here in the USA, the movement toward waterborne paints has been building momentum for several years. Already, parts of California mandate the use of waterborne paint. Although Michigan hasn’t mandated the switch to waterborne paints, it has one of the highest numbers of waterborne compliant shops in the country. And up north in Canada, all paint shops were mandated to make the switch in 2009. Although many painters in the US believe the National Rule of 2008 mandated the switch to waterborne paints, it just regulated the amount of VOCs in coatings. If a solvent meets these standards, it can still be used.
Despite the fact that solvents are still widely used in the automotive paint industry, we’ve all seen the writing on the wall. The big paint companies have been developing and refining their waterborne coatings to meet what they expect will be increasingly stringent VOC requirements. With this in mind, we thought it would be helpful to share with you some information about making the switch to waterborne paints and why it won’t be as bad you might think.
What Auto Paint Spray Equipment is Needed for Waterborne Paint Application?
The first question everyone asks is if they’re going to need new spray guns and spray booths to use waterborne paints. Let’s tackle the topic of spray guns first.
The good news is that most spray guns used for solvent-based paints can also be used with waterborne coatings. You’ll have to consider the needle and nozzle sizes recommended by the paint manufacturer, of course, and your cleanup routine may need to change a little. If you’re using traditional spray guns, you’ll need to first clean with water to remove any waterborne paint still inside, then rinse with solvent or alcohol to remove any water. Because older guns have uncoated steel inside, they will corrode if you only use water is to clean them. The newer, waterborne paint-ready guns have stainless steel or coated parts to protect against corrosion, so they can be safely cleaned with just water. These newer guns designed for waterborne paints are also optimized for atomizing waterborne paints.
So, what about your spray booth? Although you won’t need a whole new spray booth, you’ll need something capable of moving large amounts of air for drying the finish. When you’re working with waterborne paints, air movement is the most critical factor influencing dry time. This is what gets the water to evaporate from the finish. It’s true that atmospheric humidity does have some influence on evaporation, but evaporation time is shorter if air is moved rapidly over the painted surface.
There is a good chance your existing spray booth doesn’t have the ability to move the amount of air required for drying waterborne finishes. Fortunately, modifying it isn’t a major hassle or expense. You’ll need to add special blowers called venturis. A movable venturi, or several venturis, can be placed in your booth to keep air circulating over the vehicle you’re working on. If you’re adding a waterborne-specific booth, venturi blowers can be permanently installed.
Ah, but what about dust and dirt in the air? Isn’t it going to end up being blown onto the drying paint? Good question. Yes, the air running through the venturis blowers has to be completely dust and dirt-free. This means your booth will have to be well sealed and any air running through the venturis will need to be filtered.
Getting Your Crew Up To Speed with Waterborne Coating Techniques
Although many old timers grouse about making the switch to waterborne paints, nearly everyone who has switched has found it really wasn’t hard. In fact, most feel little nostalgia for the old ways and find the waterborne paints give them the ability to easily apply coatings with little or no texture. Besides posing less of a health hazard to painters, the lower VOCs of waterborne paints are also significantly less harmful for the environment.
If you’re looking for help with getting your painters trained in the use of waterborne paints, most paint manufacturers have regular training classes to help both new painters and experienced painters. Check our online calendar for the dates, and times of upcoming automotive paint training courses.
Final Thoughts On Waterborne Paints
We fully expect the government will eventually mandate the switch to waterborne paints due to environmental pressures and concerns. However, there are benefits to making the switch before being required to do so.
For instance, cure time is shorter with waterborne paints—provided you have venturi fans in your booth. Also, color match, metallic orientation and blending are all improved with waterborne base coats. Perhaps one of the biggest benefits, though, is the increased safety of your paint crew.
Need some financial motivation? Since the more expensive chemical solvents are dramatically reduced in waterborne paints, they will likely come down in price as waterborne paints become more prevalent. Consider, too, the time you can save by curing waterborne paint finishes with fast cure time clear coats. Also, running venturi blowers with compressed air is far less expensive than running paint booth bake ovens.
From our perspective, making the switch to waterborne paints offers only upside for the industry. The adjustments needed to make the switch are not significant or overly expensive, and we cannot envision the switch having any negative effect on a shop’s profitability.