Automated assembly processes usually make a lot of sense from a cost
standpoint—but not always. Some short-run products simply can’t justify the
upfront costs of creating machined robotics fixturing. CMP Advanced Mechanical
Solutions (Chateaguay, Quebec) recently found a way around this automation
barrier as it relates to the robotic welding of electronics enclosures.
Instead of machining its welding fixtures, CMP has begun to turn them out
with a computer-controlled laser cutting system. Working from the 3D models of
the metal enclosures, the company’s engineers first create a related model of
the welding jigs and fixtures. This model, in turn, drives the company’s
4000-Watt Amada laser, which slices out the individual fixture components. These
laser-cut components quickly snap together into finished welding fixtures, ready
for deployment on the robotic welding line. The time needed to create complex
fixturing falls “from weeks to days or even hours,” says Steve Zimmermann, CMP’s
The resulting cost reduction can be significant. Zimmerman estimates that the
new laser method reduces fixturing costs by about 50 percent. He attributes the
savings to four factors: For one, laser cutting has an inherent advantage
in speed. For another, it makes more efficient use of materials and can create
fixtures from plate stock. The laser cutting also reduces the hefty labor costs
associated with the highly skilled machinists who do fixture work. Finally,
laser cutting enables the snap-together fixture designs that need less assembly
work and interface with the robots more quickly.
The savings in fixturing costs ultimately translate to an overall enclosure
cost reduction in the neighborhood of 30 percent, Zimmermann says. This savings
would apply to a variety of jobs whose production volumes once precluded
automated welding. With the laser fixturing method, jobs measured in the tens of
units rather than hundreds or thousands can take advantage of robotic welding’s
productivity advantage—not to mention its more consistent weld lines and
improved dimensional tolerances. And even jobs that will do have the product
volumes to support robotic welding can benefit from the laser cut fixtures.
These jobs often start off with machined, manually assembled enclosures until
the product’s production ramps up, Zimmermann notes. Laser cutting can cut out
that middle step. “We can skip the machining and go right to automated
production from the beginning,” says Zimmerman.
The first job to use CMP’s laser-cut fixtures, an enclosure for an automatic teller machine, whose initial production run came to 50 units. And Zimmermann reports the method is currently under consideration for a telecom enclosure that requires just a ten-unit run.
CMP’s laser cutting and automated welding lines can accommodate enclosures up to 36 x 36 x 96 inches. For more information, go to www.cmpdifference.com
CMP has started to
create complex welding jigs, like this one, from laser-cut components,
cutting the cost of welding fixtures in half and shaving 30 percent of the
cost of metal electronics