One of the first clues that Precision Plus is different from other machine shops was a gentle clicking noise. The sound emanates from more than a dozen mechanically driven Swiss-type lathes at the center of the shop floor. Lined up in neat rows and serviced by obviously newer barfeeders, these machines cut uncovered, without the noise-damping enclosures that characterize the shop’s CNC machines. A closer look reveals a half-dozen or so tools simultaneously plunging in and out of the workpiece as the cams rotate.
Some of these machines had already been producing parts for years by the time the company moved to its current location in Elkhorn, Wisconsin in 2000. Under the leadership of company president Mike J. Reader, the company has since added various newer CNC equipment, including Miyano ABX and BNX two-spindle lathes as well as multiple Star and Tsugami Swiss-type CNC lathes. And yet, Precision Plus still relies heavily on equipment that operates in much the same way as it did when Reader’s father, Phil, first purchased the company in 1988 – that is, by using physical cams rather than CNCs to space out the timing and depth of cuts. Why?
This was my first question to Michael P. Reader, VP of Engineering (and Mike Reader’s son). His answer was simple: “The cam-driven machines, when they can be used, are cheaper to operate,” he says.
“For small cylindrical parts with higher annual volumes, the Swiss cam machines are very economical,” says Reader. The fleet of mechanically driven Swiss-type lathes from Tornos have lower electrical costs, and crucially can often cut parts significantly faster.
That last factor might be surprising to some, as a computer-operated machine tool seems like it should have no problem competing with a machine that has absolutely no computing power whatsoever. However, the cam-driven machines can utilize multiple cutting tools at once, with very little travel. “All the tools are at rest less than two inches from the part,” Reader says, gesturing to a semicircle of cutting tools frantically cutting a firing pin out of a thin bar. “This makes it much faster than a CNC.”
Read more: The Right (Machine) Tool for the Right Job