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Tour de Cannondale
by Lennard Zinn
Reprinted with permission from VeloNews
The Cannondale factory in Bedford, Pennsylvania,
surprised me in its radically new approach to bicycle production. As regular
"Gadgets" readers know, I've toured many bicycle factories -- but I've
never before seen such innovative solutions as I saw at Cannondale.
Until 1988, Cannondale had a factory similar
to anyone else's. It used the following methods:
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Mitered tubes were machined, and numerous
jigs were built for holding tubes during machining and welding operations.
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Tubes were ordered and inventoried in large
lots to reduce unit prices.
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New designs took a long time from inception
to delivery, because tubing suppliers had to re-tool to make the specified
tubes.
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Prototypes were built one at a time in the
factory's machine shop, and once a new design was decided on, new jigs
had to be built for each change in tubing or frame design.
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Large batches of identical tubes were mitered
together to minimize the time required for setting up tooling for each
operation; and jigging, tacking, welding and assembly operations were done
in the same large batches to utilize the prepared tubes.
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Forks had to be built or ordered from outside
suppliers for every size of each type of frame.
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Heat-treating was done in a huge oven for
four hours to allow the heat to "soak" into the tubes uniformly to the
correct temperature.
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Frames were hoisted into the oven in a $14,000
stainless steel rack that held 100 frames at a time; and all 100 were plunged
into the quenching bath together. The rack was so heavy that the oven and
quenching bath were primarily heating and cooling it.
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In between loading and unloading the rack,
the oven was idle, and so it had to be fired up again to heat treat the
next batch of frames. After heat treating, every frame was aligned.
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To finish off the production process, the
frames were painted automatically with a spinning paint-robot. Each color
change required flushing and cleaning the entire paint system.
The bottom line throughout the old process
was that bikes were assembled in quantity. At any time, Cannondale had
a large inventory of the bikes most recently produced, but a minimum inventory
of bikes that were produced a few months before -- according to how well
they had anticipated demand. If any models sold out, Cannondale had to
wait until other large batches moved through the system before they could
replace them.
All of this started to change in 1988,
when Cannondale's managers decided they wanted the company to become a
player in the worldwide bicycle industry. Instead of producing overseas,
they thought they could economically produce high quantities of quality
bikes in the U.S. -- although this would require very large changes in
the company's production methods. The job of converting the factory to
one that could produce far more bicycles in many more models while shortening
lead times fell to Dick Resch.
Resch's background as a professor of religious
studies at Loras College in Dubuque, Iowa, and a recent Yale Business School
graduate aren't ordinarily associated with the task he took on, but these
qualities may have insured a fresh outlook on his part -- one that experienced
bicycle company executives or manufacturing engineers might not have had.
Cannondale's president Joe Montgomery had confidence in Resch, and instructed
him not to waste time on simply recommending courses of action: He wanted
Resch to get started and do the job.
Recognizing that Cannondale didn't have
the kind of money to quintuple production by using traditional methods,
Resch sought to re-think every operation the company performed. The kinds
of changes he envisioned hadn't been undertaken by any bike company he
knew of, so he decided to begin them on a test basis. First, he focused
on Cannondale's sewing operations, since their short product-cycles --
two selling seasons -- and the relatively low cost of manufacturing machines
and raw materials made it possible to experiment quickly and at lower cost.
To begin everything, Resch implemented
a program dubbed CLIPS -- Cannondale Low Inventory Products System. Its
intent was to increase the flexibility of manufacturing operations by reducing
or eliminating special tooling, reducing inventory, and shortening product
cycles. Cutting operations were completely overhauled, and a new computer-controlled
materials-delivery system running on a ceiling track was installed. Batch
sizes were reduced, and new systems for monitoring and tracking products
were implemented.
Resch followed this up with a system called
CPR -- Critical Product Replacement. Under CPR, 90 percent of dealer orders
were shipped complete with only six days of inventory.
The pace and productivity that Resch created
was far beyond anything Cannondale had seen in the past. The technology
and human culture weren't yet up to the task, though. For one thing, the
innovations took far too much of the company's computer memory. Furthermore,
the drastic change required more training for the workers. The result was
that CPR was removed soon afterward as a successful experiment that was
ahead of its time. Resch's comment is that, while "the certainty of failure
is more comforting than the risk of success," he plans to re-implement
CPR in the future throughout the factory, once the overhaul of the bicycle
manufacturing operation is complete.
Bicycle factory conversion
In 1990, conversion of the bicycle factory
began. Now, four years later and only partially through the conversion,
Cannondale is building more than five times as many bicycles -- while maintaining
less inventory -- than it did in 1989. Specifically, Resch's figures show
that productivity has increased 240 percent from 1988 to 1993.
At the heart of the now patented production
system is the goal of eliminating any need for changing tool set-ups. Starting
from the beginning, a bicycle is now designed on the CAD-CAM system, in
which archetypal modular drawings of partial frame assemblies are made
and changed on a computer screen. If a new type of tubing is required,
the system designs and CNC-machines the steel swaging blocks required to
shape stock tubing into the new tubes on an in-house swaging machine. The
computer then instructs laser cutters and electric arc plasma cutters to
miter each tube precisely -- based on the new design -- and to cut water-bottle-boss
holes, vents, notches, and seat-lug slots at the same time. One unique
feature of Cannondale's miters is the tabs cut into the bottom of each
miter to fit into corresponding notches in adjacent tubes. These tube-cutting
operations are done in tube sets for each individual frame, since the speed
of the mitering is the same as in huge lots of, say, identical down tubes.
The quick-tighten chucks that rotate the tubes under each laser or plasma
cutter are universal and independent of tube size or shape.
The frame front-triangle tacking jigs can
hold any frame, regardless of geometry. The computer dictates the height
of the bottom of the head tube relative to the bottom bracket, and dialing
this height into the jig is all that's needed to change from one frame
type or size to another. The tabs and notches hold the tubes in their proper
locations relative to one another, and each joint is tack-welded together.
Each frame-tacking center and rear-triangle
assembly consists of two rows of certified welders who weld the tubes together.
A tracking system allows Cannondale to know who welded each frame that
comes out of the factory.
The huge heat-treating oven has been replaced
by a new, patented design with three chambers, each holding eight frames
at a time. Racks move each load of eight frames via a ceiling track. One
passes into the oven's front chamber, where the temperature is brought
up to that of the inner chamber, which stays constant. It then moves into
the inner chamber as another batch behind it moves into the first chamber.
After a few minutes, the first batch moves into a third chamber, which,
like the first chamber, protects the inner chamber from temperature variations.
Frames stay in each chamber for only a few minutes, since they just need
o reach heat-treating temperature briefly. The old oven took four hours
to accomplish the same thing, bringing the temperature up slowly so that
in any frame among the 100 being treated, thin tubes weren't being overheated
while thick ones were being underheated. Now, thermometer probes are screwed
into the thick and thin tubes of sample frames to monitor the heat treatment
daily.
The temperature of the quenching bath is
also monitored constantly and cooled back down to the proper temperature
after each rack of eight frames is plunged into it. This assures that each
frame gets a consistent quenching temperature. It no longer varies as it
used to -- based on where the frame was in the lattice of 99 other frames
and how much the quench bath heated up when the huge steel rack carrying
the frame was dropped into it.
Cannondale used to use a very expensive
automated frame aligner that would check and correct the alignment of every
frame in the softened stage, immediately after heat treating. After implementing
the new heat-treating system, the company found that the machine wasn't
doing much, since the frames were coming out in much better alignment.
Since their new tracking system tells the engineers everything that's happened
to every frame, they continued to tweak various steps to improve the alignment
further. They now find that a misaligned frame is very rare, so they took
out the expensive automated aligner. Engineers still check the alignment
of every frame, but if they find one that's off, it's discarded.
Where forks used to be stocked with every
length of steering tube required, Cannondale now only keeps very long,
unthreaded ones on hand in each model. They have a machine that can cut
and thread steering tubes after painting, and they only prepare forks to
order now.
Painting used to be done by an automated,
rotary spray-robot. But the robot has been removed to provide more flexibility
in color choices. It was also removed because the new paints required by
the Environmental Protection Agency don't smooth out as well without the
volatile organic components they used to have, and forcing them through
the old rotary atomizers yielded less-consistent results. Removing the
solvents in the paint -- according to the new regulations -- also requires
the paint to be catalyzed to cure, which means it will harden up inside
paint equipment. Spray gun makers, DuPont, the Environmental Protection
Agency and Cannondale have worked together closely to come up with a new
system. Frames are now hand-sprayed with guns that mix the paint and the
catalyst together in the stream ahead of the nozzle. Since the paint won't
harden in the guns, a painter can have numerous guns to spray many different
colors. He or she simply paints frames in one style until a new instruction
tag comes along the conveyor, then switches to the new color; there's no
cleanup in between.
In the future, Cannondale plans to oversee
the entire operation with a computer program designed by University of
Connecticut engineers. Each day, the jobs scheduled for that period will
be put into the computer, which will come up with the most efficient flow
pattern. If a machine breaks down, the computer will come up with the most
efficient production routing without it. The computer will also alert managers
to which stations will be idle at which times during the day. Using these
stations during such time would result in no increase in output, so this
"spare" time will be utilized for other workers to be trained on that station
or for maintenance of the equipment.
Monitoring the quality of the products
is an extensive testing lab. It's very well equipped in terms of repetitive-fatigue-testing
and impact-stimulating machines. Ongoing research in real-world conditions
is conducted by wiring bicycles with strain gauges connected to portable
computers.
Reaching the first plateau
Cannondale has reached its first goal --
where each worker is able to do his or her job on any type of frame with
standardized tools at each station. The next plateau is to have specific
information travel with each frame, so that it can be built accordingly.
This would allow each frame to be custom built at the same rate that identical
frames are done now. Prototypes are built on the production floor along
with the other frames -- but someone has to keep track of them. Doing so
with automated tracking in the future won't be a simple problem to solve,
since bar code tags would burn in the heat-treating oven; but Resch feels
they're close to a solution.
An impressive test
It seemed as though a good test of the
flexibility of production at Cannondale would be to build a custom frame
for me, since my height requires a frame size beyond anything Cannondale
currently builds. I changed the design parameters on the computer screen,
and, indeed, a completely custom frame was produced alongside all the others
in a single day.
Overall, I was most impressed with Cannondale's
factory. The amazing simplicity and flexibility of some of the production
systems went beyond anything I'd seen before in a bicycle factory. I particularly
liked the willingness to re-think each operation from the ground up, rather
than throw more technology at it in order to improve it. If you can produce
a product better by simply redesigning how it's put together, then why
keep doing it the same old way?
Copyright 1994, Inside Publications.
All rights reserved.
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