by Jeff Hahn
Metal fabrication shop increases throughput while decreasing operating costs with the addition of a new laser system
For several years now, the metal fabrication industry in the United States has either heard about or suffered a nonstop barrage of doom and gloom over jobs and business flowing offshore to China and other fast-developing countries. However, as shops here in the U.S. have invested in updated fabrication technology, that trend is reversing itself in the most unexpected corners of the industry.
Metalwerx, a six-employee fabrication shop in Fredonia, WI, specializes in fast-turnaround jobs for a wide variety of customers, including automotive, railroad, and military. Up until last year, the company ran its jobs across a trio of 2-kW lasers that once performed adequately—that is, until the company began thinking about the future.
Until recently, 70 percent of the company’s revenue came from woodwork—etching, cutting, and the like. However, virtually all of that work migrated to China. So to rebuild and refocus itself on metal fabrication, Metalwerx put a new face on itself with new technology, in the form of a Mitsubishi LVPLUS 3015/40CFX laser.
Making the 4-kW laser machine central to its production has enabled the company to radically increase production speed, lower per-hour operating cost, and increase material utilization in one decisive stroke.
At the same time, this laser has given the company greater flexibility in the types and thicknesses of metal that it can cut. The shop typically cuts 10 different varieties of material per day in stainless steel, mild steel, and aluminum. It can cut stainless up to 5/8-in. thick and routinely cuts mild steel anywhere from 20 gauge to 1-in. thick.
A prime example of the company’s newly found production speed is a complex washer for railroad ties that the shop cuts from 3/8-in. mild steel. With its old lasers, cutting a batch of washers from a 48- x 120-in. sheet took 4.2 hours. The same job now takes less than one hour. “And now we get more parts on the same size sheet with faster pierce times,” General Manager Todd Weaver says. “Plus, we don’t have any grinding anymore.”
Part of that extra edge quality is attributable to the square-wave pulse emitted by Mitsubishi’s cross-flow resonator that allows the lasers to operate on an 80 percent duty factor, which results in cooler operation at the same cutting speeds while the 80 percent on time and 20 percent cooling off time produces a smaller heat-affected zone and better edge quality.
“We’ve eliminated a lot of secondary processes by being able to air cut and nitrogen cut light-gauge steel parts that need to be powder-coated,” Weaver says. In addition, the laser shuttle table enables operators to switch efficiently between production-quantity work and prototyping. That feature will become more critical as the company begins to do more prototype work for its new production facility in Mexico.
Another key feature of the LVPLUS is the Ncell software package that allows tighter nesting of parts so that the shop can utilize material better. One creative move is to place parts within parts—nesting jobs with smaller pieces on the same sheet as larger ones to reduce waste. Ncell software maximizes the machine’s nesting capabilities, which has helped the shop save even more money—about 35 percent per run with one particular mild steel job, Weaver notes. This helps combat the spike in raw material costs.
Metalwerx has seen significant cost savings aside from steel as well. Labor aside, operating its three old lasers was costing the shop about $90 an hour for consumables such as gases and electricity. That number has plummeted to less than $10 an hour with the LVPLUS. “That’s $80 an hour, and we’re getting more throughput,” Weaver says. “We just put in a bulk gas system, so actually our cost of gases has gone down.”
Gaining speed while decreasing operation costs has helped boost Metalwerx’s bottom line. What was a $40,000-per-month operation now generates $200,000 per month in sales with the same number of employees.
“We’ve been trimming everything we can to stay really lean and competitive,” Weaver says. “Now we have a lot of production that has come back from China. We found that with lower overhead, a lot of our current jobs were in China. Even if we’re a little bit higher per piece price, with the savings in shipping, we’re blowing them out of the water.”
Jeff Hahn is the national product manager for Mitsubishi Lasers (www.mitsubishi-laser.com).