Keep shop’s paint booth producing with preventive maintenance
Osseo, Wis.—A properly operating paint booth means more jobs delivered on time – and with fewer headaches for production and management staff. And yet, many shops fail to keep their paint booths properly maintained, often costing them productivity and increased repair costs, said Brandon Lowder, vice president of Auto Refinish at Global Finishing Solutions (GFS).
“The biggest misconception we run into all the time is that customers feel like the preventive maintenance visits are going to be costly to them,” Lowder said. “And in reality, to have somebody come in and do some minor cleaning and make minor adjustments is actually quite inexpensive, and it can definitely prevent very costly downtime.”
In doing preventive maintenance, which includes inspecting the fans, greasing the bearings, inspecting the motors and checking their amp draw, the booth technician can predict which items need attention in the future, Lowder said.
“Then they can budget for that before the booth gets to the point that it just can’t be used until those items are repaired,” he said. “The booth is pretty much the only tool in the shop that is required to complete the production process. So if the booth is down, they can’t produce any repair orders. The average R.O. in the industry is about $2,700, so for just one lost R.O. per day, it costs $270 in net profit. If the shop is down for a whole day or a couple of days, you can see it compounds quickly.”
The No. 1 maintenance mistake shops make, he said, is not following the booth manufacturer’s filter changeout schedule, which for GFS’ exhaust filters, is 100 hours, or about two workweeks.
“The primary filters typically don’t get changed as they should, and what happens is the painter needs to get the last car out, so they remove a couple of filters to get a little airflow in the booth,” Lowder said.
But in doing so, he said, the paint overspray bypassing the clogged filter sticks to the inside of the exhaust stack and exhaust fan. That compounds the maintenance needed in the future for malfunctioning dampers and imbalanced exhaust fans (which, over time, will damage the motor or bearings in the fan).
Ceiling filters typically need to be changed every 2,000 hours, which equates to six months to a year, depending on how many hours the booth is run, Lowder said. A common mistake shops make is in using subpar ceiling filters, which creates the need for additional time-consuming denib-sanding and buffing.
“Ceiling filters should be rated at a minimum of 90 percent efficient at trapping 10 micron particles,” he said. “Ten microns is the smallest particle you can see with your eye when it’s in the paint. The two most commonly rated filters are either 90 or 95 percent. Our booths are all 95-percent efficient at capturing 10 micron dust, but I’d say 90-95 percent would be acceptable in our industry for a good finish.”
And for booths with air makeup units, Lowder said, shops commonly overlook the intake filters, which for GFS units are bag-type filters, and for many others, are washable screens with a tackifier sprayed on them. The intake filter maintenance is typically recommended once per quarter, or more often in dusty locations, he said.
“I’d say more than half of the booths in America have a washable filter on the air intake, and hardly anybody applies a tackifier,” Lowder said. “What happens is it really shortens the life expectancy of the ceiling filter, because you just don’t capture enough dust.”
Exhaust fans need to be cleaned, although with proper filter replacement, that frequency is reduced. For booths using dampers in the intake and exhaust airstream instead of variable frequency drives to balance their airflow, the dampers should be checked at least once a year, Lowder said.
“Often, the linkage is broken, or they’re not working correctly,” he said. “So the shop, when they think they’re in 80/20 recirculation, they’re really not, because the dampers are not moving; they’ve been locked up because of overspray or other mechanical issues. In colder climates, that will show up where they can’t achieve the bake temperature they want. ‘The booth used to get to 180 degrees, no problem, and now I can’t get it to 120.’ It’s likely a damper issue, if they have mechanical dampers.”
Problems with the airflow switch or with the burner are also common, Lowder said. Other items needing periodic inspection include pit grates, breathable air systems, sprinkler heads, belt drive pulley alignment and belt tension, and burners.
A GFS distributor can set up an inspection schedule with a shop, which can include minor adjustments and inspections to make sure the booth is balanced and performing to specifications, often for a cost of less than $1,000, plus any filters and parts that are needed, Lowder said.