Page 25 - MetalForming June 2015

doors with new customers and indus- tries, and also with existing stamping customers for whom we provided high- er-volume production,” says Wagy. “More often, they started to ask us to develop prototypes and provide short- run production. Next came requests to cut reflective materials—copper and brass, for example. Hence the decision to make our most recent laser pur- chase a fiber machine.”
Prince also appreciates the ability, using the laser-cutting machines, to offer customers first-article parts in one day or even on the same day as requested.
“We don’t have to purchase tool- ing,” he says, “and we can allow our customers to begin validating their internal processes immediately. We do this at least two or three times per week, and we expect this need to grow.”
Much of the work cut on the two laser machines (both Trumpf models) route through the company’s six press brakes. Also dotting the floor of the 50,000-sq.-ft. plant are stamping press- es, CNC turret punch presses, welding equipment, shears and drill presses. A neighboring building houses the firm’s array of machining equipment. And, the company operates a 50,000-sq.-ft. stamping plant in Brownsville, TX.
Surprise—Thin on the CO2, Thicker on the Fiber
Touring the designated laser-cut- ting area of the shop, home to the Trumpf cutting-machine duo, we spied a somewhat surprising dynamic—the CO2-laser cutting machine was going to town on 0.060-in.-thick cold-rolled steel, while the fiber-laser machine sliced through thicker 0.312-in. steel plate.
“We often run very thin material (as thin as 0.010-0.015 in.) on the CO2 machine,” shares Wagy, “because we find that the higher gas pressure asso- ciated with the fiber machine can blow the small parts out of the blank. We get better process control on these more delicate parts on the CO2 machine.
“Otherwise,” Wagy continues, “for
parts 1 to 3 mm thick the fiber machine definitely outperforms the CO2 machine when it comes to speed and productivity. We find that the advan- tages of the CO2 machine—other than on very delicate parts—come into play for material thicker than 5 mm.”
To supply gas to its laser-cutting machine, Tella recently invested in bulk liquid-nitrogen and oxygen tanks. The tanks reside near the backdoor to the plant, enabling quick service from the firm’s gas distributor.
“We have a telemetry system in place,” says Wagy, “that alerts our dis- tributor when levels get low. This ensures that we’ll never run out of
Tella Tool’s display of fabricating work features an array of laser-cut, turret- press punched and press-brake formed parts for customers in the electronics, aerospace, telecommunications and other industries. Cutting the tubular part (left)—which goes into an aircraft fueling system—on its fiber-laser machine required the firm to develop a special cradle fixture.
cutting gases. And we’ve eliminated the hassles of cylinder deliveries and handling.”
Perfecting High-Mix Low-Volume Fab
Early in its laser-cutting adventure, Tella Tool found success earning work with very short runs (40 to 50 parts) nested onto small blanks sheared to size inhouse, or supplied by its service center. And, much of that work also required preprocessing on the firm’s turret presses, to punch holes or per- form forming operations. Now, much of the growth in Tella Tool’s laser-cutting operations is from new customers with larger order volumes—1000- to 1500- piece runs that allow the company to run 4- by 10-ft. sheets. Along with this increase in order size has come the move to a kanban system for managing production through the fabrication
www.metalformingmagazine.com
MetalForming/June 2015 23