Tim Orchard, president and owner of OMF Performance Products founded his Riverside, Calif., company 28 years ago out of necessity. The longtime off-road racer wanted more choices for high-performance custom wheels. The same man who raced alongside Bobby Unser Jr. at Pikes Peak also learned a good deal while working in metal stamping and sheet metal fabricating operations, and decided to put that knowledge to work.

TIG welding speeds improved by 20 percent when OMF switched to a 700-amp TIG inverter.

“There weren’t enough reliable, quality products with good delivery times available to market being,” says Orchard. “So, I slowly eased into it. It started off as a sideline for the first few years, and then it got so busy that I had to go full time.”

Once Orchard went all-in, he equipped his shop with enough welding and fabricating equipment to keep his operations loose: he can make running changes and custom fabricate to customers’ needs, but he eventually became hamstrung by the power draw and strength of his 350-amp transformer-based welding equipment. Running off 208-volt three-phase power, Orchard was able to upgrade to a 700-amp TIG inverter with advanced AC TIG controls and add a 350-amp pulsed MIG welder — all while increasing welding speeds and reducing power consumption.

Aluminum wheels lock in racing performance
OMF’s high-performance racing wheels are used by all types of racers, from weekend warriors on quads to professional sand drag racers, and off-road teams, like rock crawlers, dune buggies and rhinos. The company’s premier technology is its bead-lock design. Air pressure typically is the only thing that holds a tire on the wheel — a problem when off-road racers prefer to run at lower pressures to gain traction as a performance advantages. OMF’s bead-lock technology mechanically fastens the tire to the wheel and creates an airtight seal that makes it impossible for the tire to come off the wheel. Each wheel, including the inner and outer rings that are welded on to create the supporting structure for the bead lock, is built from 6061 T-6 aluminum.

Switching to a pulsed MIG process increased welding speed on aluminum by as much as 35 percent. IMG 9285, 9287, 9288, 9299:

“We use 6061 T-6 for its strength and weldability,” says Orchard. “It’s the strongest commercially available alloy that is readily weldable. There are other alloys that are just as weldable, but not strong enough, and other alloys that are stronger but aren’t weldable.”

OMF outsources its polishing, plating and powder coating, but all machine work, assembly and welding is performed in-house. The company relies on an impressive combination of CNC machines, extrusion dies, and forging dies to create each wheel, and inverter-based welders to weld on the inner and outer rings: Miller Electric Mfg. Co.’s Millermatic^® 350P pulsed MIG welder and the Dynasty^® 700 advanced AC/DC TIG welder.

Pulsed MIG increases weld speeds by 35 percent
“Most of our bigger wheels — 14 in. and above — are 356 aluminum castings that become a huge heat sink. We found it almost impossible for any welder to keep up with it until the Millermatic 350P. The fact that it has built-in pulsing capabilities is huge for us.”

Larger aluminum wheels weigh in excess of 30 lb. and are cast in 356 aluminum in thicknesses ranging from 3/8-in. to 3/4-in. Welding the larger (14-in. and up) wheels with the old 350-amp TIG machine required preheating with an oxyacetylene torch up to 400 degrees F. For a time, OMF even used an oven before concluding that was too difficult to maintain.

“We’re probably 30- to 35-percent faster now. No preheating whatsoever. Of course, when we were TIG welding with the older machines, we would have to tack the pieces together and physically preheat them with an oxyacetylene torch, and then weld them. All that is gone from everything we do now.”

Pulsed MIG eliminates or minimizes burn-through, distortion, heat-affected zone size and loss of mechanical properties. Because aluminum quickly transfers heat from the weld, it takes more energy to establish the puddle, ensure good fusion through a pulse of peak energy, and control heat input (hence the previous need to preheat while TIG welding to regulate temperatures). Pulsed MIG also provides excellent directional control over the weld puddle and allows the operator to control the appearance.