Carbide Grinding Co. Inc. was a toolmaking business established in 1974 that developed a solid reputation for manufacturing specialty products for Milwaukee-area manufacturers, like Snap-On and Harley-Davidson. Kevin Cranker bought the company in 2003, re-established it with an edgier brand – Gorilla Mill – in 2005, and now he oversees a larger and more diversified enterprise that continues to mark progress in its capabilities. It counts nearly 50 employees and 300 distributors worldwide, supplying specially designed and manufactured tools to a wider array of automotive, defense, and aerospace manufacturers, like Boeing, SpaceX, and Blue Origin
Still, Cranker maintains it’s the job shop customers that give him the most satisfaction. “They're the guys who keep our work up,” he detailed. “When one of the big guys goes away it stings a bit. But then we have a number of small mom-and-pop job shops that we love doing business with because they’re always there and just always buying.”
He’s also pleased with the role that ANCA CNC Machines has played in Gorilla’s Mill’s progress. Having invested in – and being disappointed by – a European-built tool-and-cutter grinding machine more than a decade ago, Cranker decided to invest in ANCA’s RGX tool-grinding machine, for re-grinding and low-volume production.
The machine is now just one of 17 ANCA machines operating there. “I've been buying a couple a year pretty steadily here for the last five or six years, and probably we’re going to need some more here before 2022.
“We have several RX7s,” he continued. “Several MX7s, a couple of TX7s, and now we’ve got a bunch of FX7s. It's a mix of all different older ones and newer ones. I really, really like the new ones with the linear motors, which work really well.”
Cranker explains that linear motors made by ANCA Motion offer a “night and day” difference versus ballscrew motion, providing greater precision and speeds, and much more durability in a workshop where a lot of carbide sludge is generated.
Geometry lessons
ANCA’s novel simulation software has been another enabling factor in Gorilla Mill’s progress. According to Cranker, ANCA 3D CIMulation took the “heartache and headache” out of designing the geometries of the patented four- and five-flute mills he designed with Mark Greenwood.
“The GM team quickly identified the value in ANCA 3D CIMulation in its assistance to designing and developing new tool geometries without actually grinding a physical tool,” recalled Russell Riddiford, ANCA Inc. general manager. “Then, they take that design to the ANCA machine, and they get the first tool off the machine perfectly as designed in the 3D CIMulation.”
According to Cranker, there would be “just no way we could do it (tool development)” without the 3D CIMulation.
“We were able to mess around with geometries in a virtual space and not waste materials and machine time and everything else,” he added.
“But nowadays the simulator has just gotten so much better with all these new additions and the fact that now you can make blueprint drawings from it, and you can just do a whole lot more.”
One software feature that gets regular use is ‘tool balancing,’ introduced in ANCA’s ToolRoom RN34 grinding program. This software has been “a huge help,” mainly for designing single-flute routers, and helping Gorrilla Mill technicians to develop new tools for high-speed machining that will not produce noise and chatter – or damage workpieces.
Lights-out machining
Levels of user friendliness and automation options available on ANCA machines also have advanced along with Gorilla Mill. The need for “cross training” its fast-growing workforce is minimal, and most of the workshop’s machines are operating with the same ANCA software.
“Plus,” Cranker reported, “we have all of our machines tapped into a network; We can just manipulate toolpaths and tool programs right in our simulator and then shoot that over to whatever machine they’re needed at.”
Every machine is equipped with a robotic loader -- either a pallet-style or a newer AR300 unit -- helping to make lights-out work possible: The daytime hours are for custom and short-run production, while the third shift runs unmanned.
As Gorilla Mill grows its staff and revenues -- which have risen nearly 900% since the rebranding -- Cranker estimates it will continue to invest in ANCA FX and MX machines, as well as robotic options to go with these.
“We currently have the ability to make 3,500 endmills per night, if need be, and that's huge for us,” Cranker said, recalling how the automation effort started on the first RGX machine.
“It can be tricky if you don't know how to set things up right, and ANCA’s done a pretty good job of trying to keep complications to a minimum. But we honed our skills, and every time we’ve moved up we’ve bought another loader, because I really want to be able to make tools lights-out.”