Mestek Machinery will be using this month’s AHR Expo to introduce a machine that officials say will save energy while allowing greater shop efficiency, thanks to its ability to perform sheet metal fabrication with heavier gauge metal.

The machine is the Max-Stitch 1.6i, which is part of the ISM by Lockformer line. Company officials say it is the strongest and most versatile single wire stitch welder available. And it works with materials up to 16 gauge (1.6 millimeters) in thickness — a big improvement over most other options, according to Bryan Timmerman, Mestek’s vice president of sales and spiral product development.

“In the past, any of your fittings that were (thicker) than 20 gauge you had to spot weld them and seal them,” he said. “So you used more material and labor. And the finished product didn’t look as nice.”

In the case of the Max-Stitch 1.6i, it uses substantially less energy than comparable units, officials say. Similar to ISM’s existing Max-Stitch 1.0, it uses a pneumatic roller clamp, eliminating the need to make adjustments and speeding up the loading process. The Max-Stitch 1.6i can make welds stronger using more heat at the beginning and end of a piece, while welding at cooler temperatures in between the ends, which helps eliminate the warping of longer pieces. And it saves 20-30 percent on energy consumption.

“A stitch welder is the way to go because it creates an airtight seal and it’s faster and uses less material,” Timmerman said.

Something else that makes the Max-Stitch stand out, Mestek officials add, is that pairs well with other Mestek equipment, especially for making round fittings used with spiral ductwork.

An example is ISM’s gore locker, the Gore-Max Plus 1.5. Officials say its capacity matches well with the Max-Stitch 1.6i, since it can also handle 16-gauge material, making it an ideal pairing for creating round fittings. It can create standing rib diameters from 4 inches to 60 inches. It has the ability to flange/swag on one end while closing a seam at the other. And the standing seam it creates does not need additional sealing or painting.

The Gore-Max Plus will also be on display at the AHR Expo.

Fabricating round fittings is a much more streamlined process than fabricating traditional duct, Mestek officials point out, especially with a stitch welder like the Max-Stitch.  

“If you’re going to make round fittings, you need a lot fewer machines than (you do with) rectangular,” Timmerman said. “Essentially you (just) need a machine to cut the blanks out, whether it’s a laser, a plasma or a shape cutter.”

From there, the process goes quickly.

“Once you cut the blanks out, you need to roll them, so you need some sort of roller,” Timmerman added. “Once you do that, you have to close the seams. You either do it with a spot welder or a stitch welder.”

Timmerman recommends a stitch welder like the Max-Stitch 1.6i, since it can handle 16-gauge metal using a single wire when similar units can’t handle anything thicker than 20 gauge.

“Nobody has a 16-gauge stitch welder,” he said. “This stitch welder can be used for any longitudinal seam that can have a five-sixteenths overlap,”

Timmerman said the Max-Stitch can also be beneficial to shops that don’t make spiral duct, thanks to the efficiency improvements it offers.

The equipment will be on display at booth No. 5323.