Shop Evolves Into CNC, Away From Multitasking

When Slavko Grguric became part owner of a cutting tool business in 1978, his screw machine inventory consisted of Brown & Sharpe machines. Once the company invested in more complex CNC machines, the machines drove the business to find more complex work.


When Slavko Grguric became part owner of a cutting tool business in 1978, his screw machine inventory consisted of Brown & Sharpe machines. His shop created tools for the nuclear fuel industry. “The most difficult to machine was a recess tool that could be cut off with absolutely no burr on the back,” he explains. His shop’s part runs were all over the board, anywhere from 50 pieces to 10,000 pieces or more.

Then, the shop began outsourcing its tooling and started implementing carbide tools, which led to longer tool life. “Our machines never sat for more than 5 minutes without a tool,” Mr. Grguric says. “We reset the machine when we were finished, and quick-change and presetting was our driver at that point.” During this time in the late 1970s and early 1980s, not many people were operating their screw machine shops as he was, doing several jobs at a time at high frequency, he adds.

When CNC machine technology gained popularity in the 1980s, Mr. Grguric was ready to let go of the single-spindle screw machine concept and delve into these more sophisticated machines. “I saw tremendous potential in CNC machines,” he says. “However, our partners were resisting changing our vision, so I left the company.” Less downtime, interpolation, contouring, finishes and high precision were all traits that attracted him to the CNC machining concept.

His eagerness to explore this new technology prompted him to take a leap of faith when he began Acroturn Industries Inc. (Brampton, Ontario, Canada) in 1988. Starting out with Citizen sliding headstock machines and small turning machines, the shop’s technology included profiling and variable speed. Then the company invested in Miyano’s newly developed CNC machines with quick turret indexing. “We could have machines with two turrets and apply form tools; we could do our profile turning or profile boring, or we could use form tools. We had the best of both worlds,” Mr. Grguric recalls.

As Acroturn evolved and began doing larger work, management was forced to buy larger equipment. “We bought a couple lathes with a 4 1/2-inch spindle and a 16-inch chuck,” he says. “The index speed used to be a 10-second indexing time and a 150-feet-per-minute rapid rate. Currently, we can do a 2,000-feet-per-minute rapid rate.”

Once the company invested in these more complex CNC machines, the machines drove the business to find more complex work. Today, 60 percent of the work the 45-employee company does is in the aircraft industry—primarily landing gear and flight control parts. The other 40 percent is in the high-precision commercial industry—primarily injection mold nozzles. “Landing gear requires a lot of titanium, alloys, steel alloys, aluminum, bronze and some copper,” he adds.

For the Acroturn team, it’s critical to invest in the latest equipment in order to keep up with competition and customer demands. “We always change or add to our equipment,” he says. “As soon as our equipment repairs exceed the depreciation value, it is time for a change. I figure that new machines have a 5-year equipment life. However, some machines are less and some are more.”

While migrating into the world of CNC technology, Mr. Grguric decided not to sign on to the machining concept of multitasking, as many of his counterparts have. “My logic is that one piece of equipment capable of doing different types of work is much too expensive,” he explains. Instead, his shop turns parts on a turning machine and mills parts on a milling machine, and transfers the parts from one piece of equipment to another. These two pieces of equipment combined don’t add up to the cost of one multitasking machine, he adds.

“I have a lot of people tell me that if you are doing 70 percent turning and 10 percent milling, do it on a lathe with rotating tools,” he says. “But if you get up to 20- to 30-percent milling and balanced turning, you are better off to split it into two different operations because the machines are better suited for each type of job.”

Select customers of Acroturn are not only benefiting from the company’s part production, but also parts assembly. Moving forward, Mr. Grguric says one of his goals is to do more of these system assemblies for more customers. “We are already making parts, so why aren’t we assembling them?” he says. The potential danger is that it could be a big failure if it is not implemented properly. “Many auto parts makers went into sub-assembling and went through a tremendous loss of money due to not knowing how to quote an assembly. Suddenly, they had no engineering department to design how to put it all together.”

He continues, “A relatively small to medium-sized screw machine shop only making parts should be farming those parts out to Chinese machine shops. Then, they can focus on assembly. U.S. screw machine shops should also partner up with another shop or two. Then, they could sell these parts to OEM auto manufacturers or Tier-One suppliers. Exclusively making parts will eventually be a thing of the past.”

Since Acroturn’s beginnings, Mr. Grguric admits that the company has changed about five times over its course by applying several different machining concepts to its work. Its success stems from the fact that the company has come a long way from using sliding headstock machines and stands out from its competitors with its own business philosophies and goals.

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