Quality Craftsmanship, Exceptional CNC ControlJan 28, 2015
Right-angle head compensation is essential to accurate, repeatable milling of guitar necks at C.F. Martin & Co. — easily accomplished with its Fryer machines, controlled by Siemens Sinumerik 840D CNCs.
The challenge of repeatable product performance is not new to C.F. Martin & Company in Nazareth, Penn. Six generations ago, C. F. Martin Sr. launched the enterprise, producing guitars entirely by hand, one by one, with very little effort at standardization. And that exceptional attention to detail has had advantages: over the decades, guitar legends like Gene Autry and Eric Clapton, and newer starts like John Mayer, Ed Sheeran and Hunter Hayes have relied on the consistently distinctive tone, treble, and bass specific to Martin acoustic guitars.
Production of guitar forms and structural parts has become more standardized over the years, but it’s still a highly involved process that requires exceptional craftsmanship and attention to detail. “I think every manufacturing company needs to embrace technology,” said Terry Kline, Martin’s manager of tooling and machinery. “Technology and craftsmanship go hand-in-hand. People are amazed by how much handwork still goes into our guitars. We’ll build a neck and a body and then assemble the two elements together, which makes that guitar come to life.”
When C.F. Martin & Co. learned that its machine tool builder had exited the market, it approached to Fryer Machine Systems when it required new machines to address planned production increases. At the same time, it took the opportunity to upgrade the control technology with Sinumerik CNCs.
Customized support — “We use right-angle head aggregates in our CNCs,” explains Mark Bickert, engineering project manager at Martin. “We needed to find a machine builder that could give us right-angle head aggregate capability in conjunction with right-angle head compensation and a high-rpm spindle.” Fryer Machine Systems has a reputation for building reliable production machines with unexpectedly advanced features and functionality. It also happens to be the largest purchaser of Siemens controls in the United States, and the customizable aspects of a Fryer machine often are attributed to the versatility of the Siemens controls on board. This time, however, Martin needed to be certain that the new Fryer machines would perform as expected.
“Anyone can sell you a machine with a controller on it and say, ‘Here you go,’” Bickert said, “but that’s not what happened this time. We were buying a machine through a Fryer dealership, and the machine had a Siemens control. Siemens invested their time in us during our transition and set-up. They really excelled.”
Bickert explained a potential constraint to the transition: all-new milling programs might need to be written for the Fryer machines, including the right-angle head cutter compensation programs, which were essential. “Siemens not only gave us the right-angle head cutter compensation we wanted and the ability to do it properly, they also helped write the programs,” Bickert says. “They took the programs that we already had for cutting parts on our existing machines and reconfigured them to work in the Fryer machine with the Siemens controller.”
Castings machined in-house — Having made a smooth transition to the new Fryer machines last year, Martin also has advanced its ability to perform right-angle compensation milling. The shop has eight Fryer/Siemens machines now, using one for the tooling and machinery operations and seven for various other guitar production step. The company’s machinists combine modern CNC technology and Old World craftsmanship to create the fixtures, tools and expertise that comprise the mystique Martin guitarmaking.
Martin also found a way to bring previously outsourced operations in-house, a step that has improved repeatable production quality and reduced production costs.
“The machining of our castings (the permanent molds used to shape guitar forms) had been another hurdle for us,” according to Terry Kline. Until the company invested in the Fryer machines with the Siemens controls, Martin had outsourced the machining of its guitar body castings, and the results had not been reliably consistent. “Now, we’re holding close tolerances on our guitar body castings,” Kline said. “The quality of the castings is consistently accurate.”
CNC technology meets craftsmanship — On a daily basis, C.F. Martin manages are able to see what is possible when CNC technology and craftsmanship work together. “Without CNC technology, we’d be still carving out all our necks by hand, and that’s just not efficient enough to compete in today’s world,” Kline said. The confluence of technology and craftsmanship has been an organic development for this 180-year-old guitar company, with both each factor complementing the other.