The Benefits of a Nitrogen Painting System
Chelsea Hebert, body shop manager at Barker Buick GMC in Houma, La., was having big problems with the old air compressors in his paint department. The compressors had oil problems and poor air quality. And his painter was having orange-peeling in the jobs he produced.
“I was looking for a way to improve that painter’s product, and make him more efficient,” Hebert says.
Hebert came across a system called Nitrotherm in 2008, which uses nitrogen for paint application as opposed to compressed air like he’d been used to.
“I was told the system would help eliminate the orange-peeling and issues caused by poor air quality,” Hebert says, so he decided to give the system a try. Hebert signed a five-year lease for the Nitrotherm system, running him $1,400 a month.
Not only did Hebert solve his orange-peeling problem—the uniform-sized nitrogen molecules give better coverage of material, reducing those pesky voids in the paint. But the benefits from that investment have gone far above and beyond what he initially hoped for.
Francis Heckendorf, president of Painters Supply Co. Inc., a PPG jobber in Englewood, Colo., says painting with nitrogen can improve your transfer efficiency, reduce bake time, eliminate flash time, and allow you to achieve a better quality of finish.
Nitrogen-based systems have decreased in cost by about 50 percent since the technology was first introduced nearly six years ago. The Nitrotherm system has since been upgraded to a system called Nitrotech Spray, which costs $30,000 for a one-booth set-up. The industry’s other nitrogen system, called NitroHeat, just became available for purchase in 2010. That system can connect to two paint booths, a cost of $35,000, but can also be customized for just one booth for $30,000.
Yep, it’s a hefty investment to be sure. But before you balk at the cost, take a look at your potential return on that investment.
Hebert has reduced paint material consumption by an eye-popping 30 percent, which amounts to roughly $7,000 in cash savings every month. “We’re making 23 percent net profit on paint materials,” he says, noting net profit on materials was in the mid-teens prior to using the system.
Hebert’s savings in paint materials alone pays for the monthly cost of the system, and still puts about $5,000 back into the company’s pocket every month.
So what makes nitrogen so good? It’s better than compressed air because it contains no moisture and the molecules remain a uniform size upon application. Here’s why:
• Nitrogen is anhydrous. That means it has no moisture, says Grady Olson, president of Carbondale, Colo.-based N2 Spray Solutions, which distributes nitrogen-based equipment. The lack of moisture reduces flash times, decreases bake times, and ultimately improves cycle time.
• Nitrogen is inert. That means the molecules don’t expand or contract like compressed air does, Olson says. The molecules are a uniform size and provide a more solid layer of paint. That means fewer coats of paint have to be applied, which reduces your overall paint consumption.
night and day. The paint appears so much crisper.”
— Doug Dennison, tech representative, Painters Supply
How It Works
The Nitrotech Spray system takes atmospheric air from your existing air compressor and runs it through a membrane. The membrane traps the nitrogen and removes all moisture out of the air.
The nitrogen is circulated back through the membrane, adding back in some of the other materials that were discharged from the air—like argon, carbon monoxide and other trace gases. That combination of gases produces different sized molecules, which gives a tighter mill build, says Mike Haydell, president of Haydell Industries, which distributes the Nitrotech system. From there, two key things happen:
• Ionization. The gas is sent into an ionization chamber where it’s given a positive or negative charge. Haydell says this ionization process helps improve transfer efficiency of the paint when it’s applied because the electric charge causes the paint to be drawn into the panel you’re painting without bouncing off into overspray.
• Heating to a controlled temperature. The gas is sent to a delivery hose, which heats the gas to 130 degrees and controls precise delivery temperature.
That’s important because changes in atmospheric temperature change the viscosity of the paint you’re applying. Painters have to adjust the pressure they spray with depending on changes in the air temperature throughout the day, Olson says. By heating the nitrogen, the pressure you spray with can stay the same throughout the day no matter what the air temperature is doing.
The NitroHeat operates in a similar fashion and sprays with 98 percent pure nitrogen, but doesn’t have the ionization process and doesn’t add other gases back into the nitrogen, Olson says.
The NitroHeat and Nitrotherm systems were tested side-by-side during a four-day test at Auto Body Speed Shop in Jacksonville, Fla.
“The two systems are both very equal,” Olson says, noting the tests didn’t reveal any differences between the two.
As an owner, you’re always trying to justify the cost of things, says Ken Moss, owner of Pro Auto Collision in Centennial, Colo. Moss has been using the Nitrotherm system since 2008. The system does cost about $30,000, but your material savings alone will quickly pay for the system, Olson says. And the rest of these benefits are like extra credit. Olson says the nitrogen does the following:
• Eliminates puddling. The nitrogen systems provide a perfect mill build—a solid layer of paint. The molecules in the paint are a uniform size and don’t puddle, Haydell says.
• Eliminates haze. “The distinction of image compared to compressed air is night and day,” says Doug Dennison, tech representative for Painters Supply. “The paint appears so much crisper.” That’s because solvent in paint creates haze. The nitrogen system eliminates the solvents in paint with heat, and you’re applying fewer coats that contain solvent, he says.
• Improves transfer efficiency. Transfer efficiency is better because the ionized material is pulled into the panel, and doesn’t allow it to bounce back off. You get better coverage of paint on the car, Dennison says. You only have to apply two or three coats of color—rather than four or five—which greatly reduces your paint consumption.
• Reduces overspray. Nitrogen carries more paint directly to the panel, and reduces overspray by about 50 percent, Olson says. Nitrogen travels twice as fast as compressed air, allowing you to shoot at a lower pressure.
Filters in the spray booth last 40 percent longer because of the reduced overspray, Dennison says. This also leads to less contamination in the paint that has to be sanded and buffed afterward.
• Eliminates flash time. There’s no flash time with nitrogen, says Moss, who used to wait 15 minutes between every coat. “You can go into the booth and spray every coat of paint back-to-back. My painter even takes the clear coat into the booth with him to apply right away.”
Moss says this saves him three hours a day, allowing him to paint three extra cars every day—and chop two days off his average cycle time.
• Reduces bake time. There isn’t any water in the nitrogen, Olson says, and excess moisture is removed from the paint in the heating process.
“The paint is already starting to kick when it hits the panel,” Heckendorf says. This allows bake cycles to decrease from 30 to 20 minutes.
“We can sand and polish cars just two hours after baking,” Moss says, noting he used to have to let cars sit overnight first.
• Eliminates reducer. The paint material is less viscous after it’s heated, Dennison says, so it doesn’t take as much reducer to apply. Moss has been able to nearly eliminate his use of reducer.
Return on investment
Shops will watch their material consumption drop due to the improved transfer efficiency, overspray reduction, and the simple fact that you don’t have to apply as many coats of paint. The timeframe for your ROI depends on the number of cars you paint. The more cars you move through, the faster the system will pay you back.
As a rule of thumb, if your shop sprays an average of 10 panels per day, five days per week, you will experience a full return on your investment in a maximum of 18 months, according to NitroHeat.
Regardless of what type of paint you use—waterborne or solvent—you should save about 30 percent on your materials, Haydell says.
Between paint and reducer, Moss says he’s actually saving 35 percent in materials every month. His monthly costs have dropped $7,000, to $16,000 from $23,000.
If Moss were to put that money back into paying for the system outright—rather than leasing it like he does—he’d be able to have the $30,000 system paid for in less than five months. That doesn’t even include the additional revenue you may be able to obtain with improved cycle times.
Moss chooses to lease the system because the company covers all maintenance costs. Olson says the filters have to be replaced once a year—costing $100 each—and the heating hose has to be changed about once a year also—which costs about $400.
Painter’s Best Friend
After two weeks of testing it, Moss’s painter begged him not take the system away. “It would be pretty hard to go back to the days without it; this has improved our entire painting process.”
Painters are able to spray more cars, make more money, produce higher quality work, and the shop manager isn’t constantly on their back complaining about how big the paint bill is, Dennison says.
And there isn’t much of a learning curve that goes along with this either. Hebert says it took a few days to learn how to operate the equipment, but there wasn’t anything new to learn as far as the painting process.
“The only thing your painters have to learn is how to not stand around for 10 minutes waiting for things to flash,” Dennison says.