Above: The 4,000 W Optiplex 3015 laser uses flying optics, which brings the laser cutting head to the metal quickly.

Agricultural OEM brings work back in-house with laser cutter, backed by 3-D tube machines

January 2014 - On every level, farming isn’t easy. It’s not the simple overalls-and-pitchfork affair that we typically imagine, at least not for big industrial-scale agriculture. Between unpredictable weather, laborer wages, and maintaining machinery, facilities and soil, there’s plenty of toil to tackle. 

Among those addressing farmers’ burdens is the Paul B. Zimmerman family of companies, based in Lititz, Pa., about halfway between Harrisburg and Philadelphia. PBZ is a diversified manufacturer, but its bread and butter are the products made under its CropCare Equipment and Zimmerman Cattle Control Equipment companies. As the names suggest, the former mainly makes agricultural spraying equipment, while the latter builds cattle gates, chutes and restraining equipment (to keep them still during milking, for example). 

The products are fabricated from steel of all sorts in order to hold up to wear and tear, as well as the occasional unruly cow. To cut the odd-shaped steel parts for its product lines, PBZ uses a trio of laser cutters from Mazak Optonics Corp., Elgin, Ill. In 2004, PBZ bought a FabriGear 150 and a FabriGear 300 in 2006, giving the company a tandem 3-D laser cutting combo for tube and pipe. In 2012, the amount of sheet metal cutting justified an investment in a flat laser. PBZ brought on an Optiplex 3015 table laser cutter for sheet metal. “One of these machines is used for the initial operation for almost all our parts,” says Keith Zimmerman, president of PBZ, now a fourth-generation family-owned business. 

PBZ’s scope of products makes it a high-mix, low-volume manufacturer. With any HMLV operation, setup times can be a challenge, as well as making sure its array of parts can be accurately cut.

“The automation features of the Optiplex greatly reduce setup time, which allows us to spend more time processing parts and less time setting the machine up. The FabriGear machines are a bit more setup intensive, although the accuracy of the parts makes the setup worthwhile,” Zimmerman says.

Managing a mix

At PBZ’s location, there are two primary buildings for fabrication—one for cutting and welding, and one for assembly. The Mazak machines are located in the first, among the usual suspects of any serious job shop: brake, CNC tube bender, saw, shear, and MIG, TIG and robotic welding.

The CropCare and Zimmerman Cattle Control work accounts for about 60 percent of the fabrication shop’s activity, with the balance spreading out to job shop work and contract manufacturing in construction or agriculture. Across all of its product lines, PBZ engineers and designs everything.

“Having the ability to cut structural tube in any shape or form you want just really opens up the possibilities on the engineering side,” Zimmerman says of the FabriGear lasers.

The bulk of what PBZ cuts is mild steel, but aluminum and stainless make appearances, too. Between the two FabriGear lasers, PBZ cuts anywhere from 3⁄4-in. round or square tube up to 10 in. with wall thicknesses of 18 or 20 gauge. “The FG 300 will cut 1⁄2 in. wall thickness, even 5⁄8 in. sometimes, the heavier stuff,” he says. 

The FG 300 is a 4,000 W machine cutting up to 10 in. (300 mm), while the FG 150 is a 2,500 W laser cutting up to 6 in. (150 mm). Both FabriGears have 3-D cutting capabilities, making their flexibility worth their weight in gold for the HMLV manufacturing there. According to Mazak, 80 percent of the laser-cutting tube market is under 4 in. diameter with thin gauge walls that do not require 3-D. The FabriGear covers the other 20 percent of the market that deals with more difficult applications, cutting thicker, heavier or higher precision workpieces, says Marc Lobit, marketing manager at Mazak.

Due to the nature of 3-D cutting disparate parts, there can be some complicated part setup involved. But what PBZ gains downstream from the ability to make multi-cut parts can often offset the costs of cutting, say, only 10 parts. 

“Once you run a part, even if it’s low quantity, you run it more and gain efficiencies if it’s a repeat part. For us, we’re a shop where a 500-piece order of a particular part is a significant order,” Zimmerman says. “We do a lot of parts, lots of jobs, where we’re looking at less than 100 pieces. We’re not a shop that would have workcells set up for making specific parts day in and day out. We need flexibility to make different things in each workcell because we don’t have the square footage to dedicate to just one operation.”

Cutting sheet

After the profile of PBZ’s business changed during the mid-to-late 2000s, PBZ farmed out its flat sheet metal cutting and the company brought on the 5 ft. by 10 ft. Optiplex 3015. It’s a 4,000 W machine equipped with flying optics, which drives the cutting to the metal quickly.

The Optiplex is a workhorse of the Mazak laser product line, geared specifically for job shop environments. It is one of the best selling lasers in North America, manufactured at Mazak’s underground facility in Japan.

“The Optiplex, our newest machine, has automatic setup features, giving our programmer sitting in the office here the ability to program parts and send it right out to the machine. The operator then loads the material and the machine takes it from there,” Zimmerman says. “By not having a lot of setup time, whether we’re cutting five, 10 or 50 parts, you have more time running and less time setting up.”

Mazak has honed its series of automated setup functions, called AO|5 Point Setup, accounting for the quick processing. The five points: torch changer, nozzle changer, automated focal distance, automated profiler and nozzle spatter removal. These focused efficiencies make for fast part turnaround and reduced operator dependency on the Optiplex compared to traditional setups that typically exceed 25 minutes. Zimmerman says it depends on how many of the available options are being changed, but most jobs take two or three minutes. There is also the advantage of it being automated, eliminating the risk of the operator making an error.

“Typically, laser operations that accommodate varied workpiece materials and thicknesses are automated by compromising cutting parameters such as nozzle diameters and condition. This can significantly affect the productivity and cost of operation, especially with today’s focus on smaller batch sizes,” Lobit says. The AO|5 system optimizes cutting even during extended unattended operation.

Integrating structural laser cutting and flat laser cutting into the design of the equipment that PBZ manufactures has added immeasurable flexibility to its processes. Using tab and slot methods in weldments reduces the amount of fixturing that is necessary, prevents operator error and speeds up assembly time, Zimmerman adds. PBZ can consistently and efficiently cut any profile into structural members using 3-D structural laser cutting. This adds an enormous amount of flexibility at the design stage. 

“We are doing things with tubes that would not be practical without a 3-D laser,” he says. FFJ