Little Giant takes flight

Brian Nielson, an automated fusion technician with Wing Enterprises, operates one of the company's robotic welding workcells. Nielson said that moving to robotic welding has helped the company's productivity increase by 25 percent to 30 percent.

Hal Wing's family business started 32 years ago as many entrepreneurs did: with a product and a patent.

Wing Enterprises' success hinged on its Little Giant® brand of adjustable ladders. Although business was going well at first, the company's patent eventually expired, and larger retailers started popping up across the country, offering a similar product at a lower price. As the Springville, Utah-based manufacturer slowly started losing its customers, it also lost employees —staff dwindled from more than 100 workers to about 20 over the years.

The company also began to realize that selling ladders one or two at a time at tradeshows and county fairs was proving to be an ineffective strategy for increasing sales. About two years after so-called big-box retailers started selling products similar to Wing's ladders, the company decided to try a new marketing plan: an infomercial (see Figure 1). The company opted for this approach because it offered a more in-depth opportunity to demonstrate the ladder's concept, versatility, and quality to a captive audience.

Marketing Pays Off

With the first airing of the infomercial, sales for the ladders more than doubled. The company added many new positions—warehouse staff, order fulfillment personnel, welders—within the following year. Eventually the manufacturer grew from a staff of 20 to a work force of 400.

To keep up with demand, the company needed to increase production of its ladders. This would prove to be difficult because at the time, production welding was handled at six gas metal arc welding (GMAW) stations. The ladders, all made essentially with the same components offered in various configurations, were fabricated using similar workstations. Basic positioners held the sides and rungs in place so they could be welded, ground, and cleaned, all by hand. Until this point this setup didn't pose any challenges. But now more space—and additional experienced welders, which were in short supply—were required to keep up with increased demand.

Figure 1 This is a scene from one of the infomercials that the company televised to boost sales.

Robotic welding seemed to be the next logical step, but the company was hesitant. Years before it aired its first infomercial, the company purchased a robotic welding system. After problems with wire feeding, birdnesting, and welding inconsistency, the company returned the equipment—and went back to manual welding.

So when the company revisited the idea of robotic welding, it had many issues and questions in mind ahead of time. Primarily, the company's concerns focused on welding aluminum. Bird-nesting—when wire tangles between the drive roll and the liner when it's being fed—as well as consistency associated with tip preparation from one weld to the next, were two of the company's concerns. The company also questioned how much its operators would need to maintain the contact tips between welds. Previously operators had to clip and replace tips that didn't end cleanly between welds.

Still, the company thought robotic welding was worth another shot, so it purchased robotic welding equipment from The Lincoln Electric Co. to see if it could address those issues and increase its productivity.

Robotic Welding: Take Two

Wing Enterprises decided to purchase robots pairs—two approximately every three months.

The first six robots the company purchased were FANUC® ARC Mate® 100iB models, each equipped with a Lincoln Power Wave® 455M, a digitally controlled inverter welding power source.

Wing produces about 12 different models of the aluminum ladders that range in price from $100 to about $800 with a variety of accessories, such as scaffolding and work platforms.

In all, Wing manufactures about 1,500 ladders per day in a 10-hour shift. The robots are dedicated to fabricating the company's most popular models in the $300 to $400 range. The robotic cells turn out approximately a combined 450 ladders per day. And, with two new cells on the way, that total is expected to jump to roughly 650.

The company found that the new robotic welding cells helped with the additional work it had undertaken. Productivity jumped 25 percent to 30 percent, said Brian Nielson, an automated fusion technician with the company. Output varies depending on the ladder configuration, but Nielson said each robot makes about 24 welds on each ladder and produces approximately 100 units a day (see introductory photo).

"These robots have been great," Nielson said. "They produce a lot cleaner and more consistent weld than manual welding, and they'll run around the clock."

A major contributor to increased productivity, he said, was that ladders made with the automated welding cells do not require postweld spatter cleanup operations.

"There really is no spatter from the robots," he said. "Not anything like the manual welding."

Nielson also attributes the excellent weld appearance the company can get on its ladders to the wire and shielding gas used: Lincoln Super Glaze® 5356 3/64-inch aluminum wire used with 100 percent argon shielding gas. The company uses a wire speed of 300 inches per minute for both the first pass and for the second, final cap pass to achieve outstanding weld appearance, according to Nielson.

In addition, the company has been able to overcome its previous and biggest challenge in robotic aluminum welding: birdnesting. Nielson said that the wire drive system works well to guard against wire tangling in the wire feeding process.

More Sales, More Workers

Ladder sales have continued to grow as the infomercials continue to air, even two years after the first one premiered. Sales have tripled, and the company is planning to build a new facility three times its original size— complete with more Lincoln Electric robotic welding cells. The big-box retailers that once threatened the company's existence with foreign products now are placing orders of their own to meet their customer requests for Little Giant ladders.

With such sales growth and an upcoming expansion comes a need for more production, more workers, more equipment, and the need to maintain the quality that has gotten the company this far.

As the company continues to grow, its managers have struggled to find qualified welders to staff its operations. Switching to welding automation has created jobs for skilled welding technicians responsible for several robots as well as for employees who perform part loading and unloading and visual inspections.

Figure 2 Twist break tests have shown that the welds are the strongest link in the ladders. Strength and aesthetic appearance are two reasons that Wing Enterprises is pleased with the results of its robotic welding investment.

Waveform Control Technology™ and software allow Wing employees to program their own waveform or choose from more than 100 standard welding waveforms preloaded into the power sources to optimize penetration, deposition, bead shape, and travel speed.

By having one or more people presetting the robots with precise parameters, fewer skilled workers are needed to operate the robots," Nielson said. "Once they are programmed, an entry-level worker can run the operation for a specific job with very good results." This, he said, is an improvement over using several manual operators who need to know considerably more about welding to keep things moving with good results.

The company uses GMAW to join 6005-T5 aircraft aluminum from 1/8 to 1/16 in. thick. Because the company performs tens of thousands of very short welds on its ladders each day, consistent starting and stopping has been one key to maintaining quality and extending welding torch consumable life. According to the company, recent twist break tests of the ladders confirm that the welds are the strongest link in the assembly (see Figure 2).

To maintain this performance in its robotic welding applications, the company chose to use Lincoln Electric's TotAL s2f™ aluminum welding system, which includes a pulse welding mode. This system is designed for robotic applications to deliver stable, consistent arc starting; clean, controlled weld bead appearance; improved crater fill to minimize crater cracking; and wire end conditioning to deliver a good start on the next weld.

Wing Enterprises, P.O. Box 3100, Springville, UT 84663-3100, 801-489-3684, fax 801-489-3685, www.littlegiant ladder.com

FANUC Robotics America Inc., 3900 W. Hamlin Road, Rochester Hills, MI 48309-3253, 248-377-7000, www.fanucrobotics .com

The Lincoln Electric Co., 22801 St. Clair Ave., Cleveland, OH 44117, 216-481-8100, www.lincolnelectric.com