Proper spray gun maintenance is something that comes across as being so simple, yet in practice, it is often neglected.
According to John Turner, General Manager, for SATA in Canada, spray gun maintenance can play a huge role in spraying efficiency and cycle time, yet it’s not always understood.
“In simplistic terms, you need to think of it as time is money,” he explains. “The more cycles you can produce out of your spray booth per day, the more revenue you can generate.”
Yet if the collision centre has a painter who is not maintaining their gun properly, and they need to stop and extensively clean it or strip it down after painting a panel or vehicle, the time required to do that can eat significantly into booth cycle time and in fact, the entire repair process. “Over a year, that downtime can add up to one or two booth cycles per day,” says Turner, which can cost the shop a lot of money. The trouble is, those losses tend to be so-called “hidden” dollars because there is no tangible evidence you can easily see from a lack of proper gun maintenance.
Stu Klein, Technical Trainer at Fix Network World, notes that in addition to paint schedule disruptions, lack of proper gun maintenance can also result in poor quality refinish results, requiring re-works which further add to booth cycle inefficiency as well as negatively impacting customer satisfaction and the shop’s reputation.
Given that a new spray gun, on average costs, anything from $300-$1,200, lack of maintenance can significantly add to that cost, especially when you look at other factors including cycle time and paint utilization. “Poorly maintained spray equipment can result in additional cost due to the need to purchase spray gun rebuild kits, ranging from $100-$250 each,” explains Corey Munn, Global Paint Applications Segment Director for
3M’s Automotive Aftermarket Division. “Additionally, poor maintenance tends to have an impact on paint utilization per job, which can increase by 10-30%, an important consideration today, since paint costs have risen significantly—around 30% alone—in the last two years.
Lack of knowledge
John Turner says that one of the biggest reasons why spray guns aren’t properly maintained is a lack of knowledge of how they actually work. He notes that often, a painter will use the gun and once finished for the day, will place it in a bucket of thinner and leave it to soak overnight. The trouble with doing that is that the thinner works its way into the air passages of the gun, which were not designed to carry liquid, especially of the corrosive kind. What happens, he says, is the thinner eats through the seals in the air passages and corrodes the internals of the gun, shortening its lifespan and effectiveness.
The proper practice is to use a gun cleaning brush and a rag with an ounce of gun cleaner following each use. Doing it this way, Turner says that a gun can be cleaned in as little as two minutes.
Like any other piece of equipment, spray guns need additional care and to get the most out of their gun, a painter needs to follow the technical data sheet for operation and maintenance. Turner recommends disassembling a gun once a month for servicing—a process which, he says, from start to finish, should take approximately 5-10 minutes.
Those painters that look after their equipment can often use the same gun for 20-25 years with few issues, he explains. Those that don’t can find themselves replacing guns in as little as six months to a year and facing multiple problems, such as inconsistent paint thickness, orange peel, runs and chipping or peeling paint. “If you can keep your gun performing like new,” says Turner, “the amount of dollars you will save over the long haul from not having to wet sand, polish, colour match, eliminate runs or reduce film build, is absolutely amazing.”