Martin Guitar

Success Story:
Martin Guitar
EDM I Milling I Laser Texturing I Tooling & Automation I Customer Service

Guitar Maker Finds Surprising Benefits from Metalcutting
Innovations
Sometimes solutions are found in very unlikely places.
Technologies can end up providing substantial benefit well
outside the area of application for which they were originally
developed. In just such a case, a world-famous guitar manufacturer
found that metalcutting innovations created by GF
AgieCharmilles were perfectly suited to boost productivity
when working with wood.
With 175 years of history behind it, Martin Guitar has long
produced the acoustic guitar of choice for some of most
renowned musicians of our time. Elvis, Eric Clapton, Johnny
Cash, Tom Petty, Willie Nelson, Sting, Jimmy Buffet and Paul
Simon are just a few of the legendary guitarists to make music
history on a Martin. The company’s influence continues today,
with prominent artists such as Beck, Dave Matthews, John
Mayer and Jonny Lang relying on the quality of Martin guitars
to convey their music to the world.
Above everything, Martin’s success has stemmed from an
undying commitment to quality. The company treats its manufacturing
processes as an art form, with many manual operations
that employees spend years mastering and perfecting.
Any change to the production processes is undertaken with
the utmost caution.
“We will not sell a guitar unless we are absolutely sure that it
meets our rigorous quality requirements,” says Fred Walters,
engineering project manager at Martin Guitar. “We view our
reputation as being on the line with every guitar we make, so
there is no room for compromise. This means our production
processes have to be as close to perfect as possible, as we
simply do not allow the production or sale of any second quality
guitars.”
While most manufacturers avoid the production of seconds for
obvious reasons, Martin Guitar is especially mindful of it. With
guitars, different woods produce dramatically varying levels
of sound quality. The tonal woods that offer the best sounding
results are in increasingly short supply and quite costly to
acquire.
This makes Mr. Walters’ job extremely challenging. As engineering
project manager, his responsibilities include identifying
potential new processes and meticulously evaluating
whether they can be successfully integrated without affecting
the quality of the finished product. Typically, processes requiring
extensive physical labor receive the most attention, as they
tend to be the most time-consuming and can be exhausting
for employees.
In searching for ways to streamline the manufacturing process,
significant inefficiency was discovered in the method for
installing frets on a guitar’s neck. Fret slots were cut all the
way across, from one end of the fingerboard to the other. The
metal fret was then installed and trimmed to be flush with the
guitar’s neck. This would leave an opening under the fret, between
the metal and wood, that would have to be hand-filled
with glue, which then required 24 hours of drying time. Finally,

excess glue was removed by hand, to achieve a smooth, unbroken
surface along the edge of the neck.
“This process created somewhat of a bottleneck in our fretting
operation,” says Mr. Walters. “In evaluating the process,
we knew that pocketed fret slots would allow us to produce
the same or possibly improve the quality of our guitar neck,
without the manual application of glue and associated waiting
time for drying. Unfortunately, we hadn’t found a viable solution
for machining the pockets.”
Pocketed fret slots needed to be 0.135” deep and just 0.022”
wide. Martin Guitar possessed several vertical machining
centers with a maximum spindle speed of 15,000 rpm. The
machines could produce the pockets, but required 69 seconds
per slot, translating into 23 minutes to finish one board.
Also, the diameter-to-depth ratio resulted in unreliable tool
performance with frequent failure. Realizing that its machines
lacked the levels of performance needed to update the
process, the company contacted Holco, Inc., its distributor for
production and inspection equipment.
were developed for shops working with metal, they have really
improved our operations.”
To get even more out of its investment, Martin Guitar has
started using the HSM 800 for the pearl inlays on its guitar
fingerboards, bridges and headplates. Taking advantage of the
machine’s high precision, Martin cuts both wood and pearl to
ensure that the two pieces fit together seamlessly. Accuracy is
extremely important to the application, as even a slight mismatch
means that the parts will not fit together correctly.
“We’re constantly looking for other ways to take advantage of
the capabilities of the Mikron machine,” says Mr. Walters. “It’s
cutting edge technology and we’ll always look for unique ways
to apply it.”
Martin Guitar is proof of the value in thinking outside the box
when considering the application of new technologies. That is
a lesson that all manufacturers should take to heart, regardless
of the materials they use or the products they produce.
“For the size of cut the pocketed fret slots required, they
needed a machine with high cutting speeds and a high performance
spindle with virtually no run-out,” says Scott Conti,
the Holco sales representative that works with Martin Guitar.
“It was a wood cutting application, but it was really calling
out for the innovations that have been made in metalworking
machines. Once we started thinking outside the box in that
regard, we found the solution.”
The suggested solution came in the form of a Mikron HSM 800
from GF Agie Charmilles. The machine’s high-speed spindle
operates at a maximum speed of 42,000 rpm and, coupled
with high feed rates, provides the required levels of performance
needed to cut the pockets without snapping tools.
Martin Guitar provided sample materials for test cuts and
found that the results were favorable enough to justify ordering
the machine.
After installing the HSM 800, Martin Guitar worked to optimize
cutting speeds and feeds. Depending on the specific material
being machined, cutting speeds vary between 30,000 rpm and
38,000 rpm and feed rates of 325 IPM to 475 IPM are used.
While it would take 23 minutes to machine a single board on
the old machining centers, the HSM 800 can machine pocketed
fret slots in just 9.6 seconds each, translating to 3 minutes
5 seconds per board. This eliminated approximately 87%
of the machining time. Additionally, with the elimination of
run-out, tool life was increased and the process achieved the
level of stability needed to eliminate the chances of producing
scrap.
“By finding a reliable way to produce pocketed fret slots, we’ve
been able to do away with the gluing process required with
the old way of installing frets,” says Mr. Walters. “In addition
to removing a bottleneck from production, it’s resulted
in approximately $40,000 per year in cost savings. Also, with
the pocketed fret slot we no longer have the thru slot showing
on the edge of the fingerboard, so the look and feel of the
neck is improved as well. While the innovations we’re using

GF Machining Solutions
GF Machining Solutions
560 Bond Street
Lincolnshire, IL, 60069
USA
Website: www.gfms.com/us
Email: info.gfms.us@georgfischer.com
Phone: 847-913-5300
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The technical data and illustrations are not binding.
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