Miller Electric Mfg. Co. (www.millerwelds.com) has developed a gooseneck-style MIG welding gun that is designed to optimize the feeding performance for 4000 and 5000 series aluminum.

The XR-Aluma-Pro MIG gun uses a two-position, series-specific tension control to provide the correct drive roll tension. Miller Electric said the tension control solves problems related to wire burn-back, erratic feeding and arc fluctuations, to help aluminum fabricators to improve productivity.

The company said the air-cooled XR-Aluma-Pro is the first push-pull gun rated for welding at 300 amps/100 percent duty cycle, and can weld with 100 amps more than other guns. Miller Electric said the higher duty cycle eliminates the need for a water-cooled gun when welding aluminum to 3/8-in. thick, so it reduces equipment acquisition costs by about $1,100.

“We increased duty cycle by developing a unique design that keep the head tube and gun body cooler. A cooler head tube and gun increases operator comfort while providing longer consumable life and lower maintenance,” Mike Vandenberg, product manager for Miller Electric, said.

Separately, to weld thicker aluminum at higher amperages, Miller offers its water-cooled XR-Aluma-Pro, that is rated for welding at 400 amps/100 percent duty cycle.

Features common to both guns include a 3 turn potentiometer for wire feed speed (WFS) control that provides better resolution and is easy to adjust while wearing welding gloves. The company said both guns also have an easy-to-rotate, self-seating head tube that provides better access to tight spots, and a replaceable feed cable liner that reduces parts cost and service time.

Miller Electric said it factory tests and pre-sets the tension on every XR-Aluma-Pro gun for 4000 series aluminum because those guns use a softer wire that requires a lighter setting, and does the same for 5000 series aluminum, which uses a harder, more abrasive wire that requires more tension. When switching wire types, operators use a screwdriver to change tension via a control on the side of the gun. The control allows one seriesspecific tension setting or the other. No other settings are possible.

Other MIG guns give operators free reign to fully adjust tension settings. Typically, operators think, “tighter is better.” Unfortunately, too much tension deforms the wire and creates metal savings.

To reduce costs associated with maintenance, Miller Electric said it designed the XR-Aluma-Pro gun with quick connectors and replaceable liners. The XR-Aluma-Pro’s quick connectors link the control cable and electrical components such as the trigger assembly, potentiometer and motor leads and eliminate the need for cutting and soldering wires and when replacing these components. When the liner wears out, some competitive guns require end-users to replace the entire feed cable conduit. The Aluma-Pro Gun uses independent replaceable liners, so customers only need to replace the liner, not the entire assembly.