Squeeze-type resistance spot welder maintenance doesn’t stop at properly dressing the tips. Repairers must remember to perform other service procedures or contract with a vendor to handle those tasks for them, an SCRS panel explained in a video released on YouTube last month.
“I see most of the equipment out there is in average to poor condition,” Society of Collision Repair Specialists-affiliated educator Toby Chess said of welders during the free video, which was Part 2 of the trade group’s educational trilogy on STRSW. Chess (Kent Automotive) likened squeeze-type resistance spot welders to cars — they’re expensive equipment needing maintenance.
Changing the coolant
One huge maintenance consideration can arise if a shop opts to use a liquid-cooled welder over an air-cooled one, according to SCRS board member Dave Gruskos of Reliable Automotive Equipment. (Air-cooled welders are largely being phased out, Chess noted.)
Liquid cooling keeps the welder’s transformer and tips cooler, meaning “you’ll get longevity out of the tips” and can produce “more welds at a higher power faster,” Gruskos said. The “big but” is that the shop is now matching liquid and electricity, he said.
“They don’t like working with each other,” Gruskos said.
Service becomes crucial, he said, calling keeping the coolant clean a “tremendous responsibility.”
“I basically have a fish tank cooling my welder,” he said.
Chess, an educator for SCRS, said he visited a shop once that never changed its welder coolant.
One flushes a radiator after a particular number of miles, and “same holds true with your spot welders,” he said. Coolant “wears out” and must be replaced, he said.
Shops should use the coolant specified by the manufacturer, according to Chess, and Gruskos agreed, calling it “very, very important.”
“It’s not simply taking one antifreeze and pouring it in,” Gruskos said. For example, some coolant can stave off the corrosion that can be a serious problem for a welder “if you’re not careful,” Chess said.
It’s “key” that the supplier, distributor and shop itself perform that maintenance, Gruskos said.
Former SCRS Chairman Barry Dorn said his shop, Dorn’s Body & Paint, does rely on the distributor for welder maintenance.
“They’re very, very user-friendly for what they do,” Dorn said of squeeze-type resistance spot welders. However, with so many variables to watch, “you have to have a partner,” he said.
In that vein, shops should ensure their distributors are “reputable companies” and ascertain that vendor’s ability to train technicians and have replacement welder parts available, Chess said. The latter isn’t always the case, he noted.
Another item potentially demanding maintenance is the welder’s “brain” itself. SD card or USB ports exist to download and install welder software updates from the Internet.
“The machines are updated at least yearly,” Gruskos said.
But that requires a technician to download the update on a separate computer and physically install it on a welder. (For how pricey the welders are, it’s kind of surprising more manufacturers aren’t putting Wi-Fi in the devices for easier or even automatic over-the-air firmware updates.)
“It’s not happening on the repairer level,” Gruskos said of those manual updates. (That seems to raise some liability or at least convenience issues, just as if the shop had failed to check every time for updated OEM repair procedures.)
Gruskos predicted spot welder and other welder updates would become more prevalent. “Everything is now being updated at a very rapid rate,” he said.
One other maintenance issue: Ensure nobody removed the strap between the counterbalancer and the welding gun itself. Gruskos said the item is an insulator.
“It’s also the first piece that body men seem to take off,” Gruskos said. “… That starts a chain reaction of problems.”
SCRS YouTube channel, Sept. 28, 2017
Society of Collision Repair Specialists, Nov. 22, 2017
Society of Collision Repair Specialists YouTube channel, Nov. 22, 2017
Featured image: Body shops must update their squeeze-type resistance spot welders using options like SD cards or USB drives. (tab1962/iStock)