Adding Swiss to the Machining Mix

Once upon a time, a shop that ran machining centers was distinctive. While many of these shops might have had some basic turning capability, manufacturing prismatic parts was generally such a shop’s primary focus.

However, operational specialization is changing. Shops are looking for ways to do more and different kinds of work for their customers. This often involves branching out by creating additional processing capability on the shop floor. It also means leaving one’s comfort zone.

Advance CNC Machining (Grove City, Ohio) is an example of a shop that has successfully recognized advantages from adding operational variety beyond its stable of horizontal and vertical machining centers. In their case, the added capability is in the form of Swiss-type machines.

Started in 1970, Advance employs 35 people in its 35,000-square-foot facility near Columbus and in another 5,000-square-foot shop in Cincinnati. The company’s focus is on two primary customer types: production parts for OEMs and maintenance-related machined components for manufacturers of consumer goods in need of replacement or maintenance parts for their equipment and facilities.

Historically, this work was performed on machining centers and consisted of prismatic parts in a variety of materials. The introduction of Swiss-type machining 2 years ago has had significant impact on the production mix and breadth of operations that Advance can supply its customers.

“The Guy”

It seems that every small to medium shop has its technical “guy” who tends to champion the application and implementation of newer technologies. In the case of Advance, that guy is Kyle Dunaway, vice president of manufacturing. We sat down with Mr. Dunaway and Advance CNC’s president,
Jeremy Hamilton, who describes Mr. Dunaway as “the technical brains behind our operation,” to find out what was behind the company’s move into Swiss machining.

An example of changing Advance’s environment came within the shop’s machining center business. Mr. Dunaway advocated moving from VMCs to HMCs to help increase throughput, efficiency, setup reductions and better match operator proficiencies. While the initial investment in HMCs versus VMCs is significant, the resulting production efficiencies and cost savings offset the price differential.

“I came out of the steel mill machining industry,” Mr. Dunaway says. “We used horizontal machines, and being familiar with them, I knew their advantages over the VMCs in place at Advance when I joined the company 11 years ago. Mr. Hamilton supported my reasoning and justification. More work across a given spindle is a compelling argument. We now have five HMCs, including three Makinos, one Okuma and one Matsuura.”

When Mr. Dunaway came aboard, Advance had some turning capability. However, it was primarily two-axis single-spindle turning centers in the 8-inch chuck range that were not very efficient from an automation perspective.

The machines required manual load and unload, manual transfer from Op 10 to Op 20. They had one machine with a subspindle, but all the secondary turned parts work needed to be performed on the VMCs. It was difficult for Advance to bid competitively for work to run on them, making turning a small percentage of the company’s revenue.

Then, 2 years ago at IMTS, Swiss-type machining caught Mr. Dunaway’s attention. “My background is in machining larger parts,” Mr. Dunaway says. “But the potential of CNC Swiss-type machines caught my attention. It looked like a promising way to augment our metalworking capability efficiently. Although I had little experience in small-part production, it seemed like an opportunity to expand our shop’s ability to competitively do different kinds of work.” Like he did on the move from VMCs to HMCs, Mr. Hamilton backed his “guy” on the move into this uncharted water.

More than the Machine

Mr. Dunaway began to research Swiss machines, checking out different models and collecting information on the various machines on the market. He settled on a DMG MORI Sprint 20-8.

“I liked the ergonomics of the machine,” Mr. Dunaway recalls, “and I also liked the matching power ratings of the main and subspindle, which take the same collets. The ability to easily access the workzone for tool changing and setup was an important component of our selection.”

In 2012, Mr. Dunaway, Mr. Hamilton and their operations manager Chet Colopy attended IMTS to “kick the tires” on various Swiss machines in order to make a decision. “We submitted a bid to DMG MORI on a Sprint 20-8, which they accepted. Advance became proud owners of their first CNC Swiss-type machine. It was installed in December 2012,” Mr. Dunaway says.

Like many shops willing to venture from their comfort zone, the question of what do we do now arises. With no experienced Swiss operators on the payroll, Mr. Dunaway decided to create one out of a sharp, 20-year-old man he identified from the milling department. With no bad habits to break, the operator was really a clean sheet of paper for getting the Swiss department up and running.

However, training a new guy in Swiss, in a shop just getting into it is not an in-house activity. An advantage that Advance was able to capitalize on is the DMG Training Academy program available at the company’s headquarters in Chicago.

“Before the new Sprint was installed, we sent the operator to the DMG MORI Training Academy,” Mr. Dunaway says. “It was an intensive 2-week program, including operation, programming and maintenance training run by one of the DMG MORI application engineers. Happily, the operator we selected was like a sponge absorbing, and more importantly, retaining, the information. With the machine installed, we started running some jobs and basically experimenting. In short order, the numbers looked good. We were in the Swiss machined parts business.” 

It Worked 

Shops of all stripes have been discovering the production advantages that CNC Swiss machining can bring to the party. Granted, the technology plays in the small-diameter range, Advance’s machines are 20 mm, but it has found the work in that range plentiful.

Proof of the concept came within 6 months of the Sprint installation, which by then was running at or near its capacity. Lot sizes varied across the sprint from small lots of 250 pieces to runs of 50,000.

According to Mr. Dunaway, “Our sweet spot is around 5,000 pieces, but we will run much smaller lots. That’s an advantage we have over some other “Swiss” houses that prefer not to quote the shorter run jobs.”

In summer of 2013, less than a year after its first machine was installed, Advance took delivery of its second Sprint 20-8. In this case, because of the machine’s automation and bar fed stock delivery, the company’s newly minted Swiss operator was able to tend both machines. Ramp-up to production was significantly smoother for the second machine, which turned out to be a good thing.

Less than a week after its second Sprint was installed, Advance received a significant order that was ideal for running on the Swiss machines. They were ready. The ability to “toggle” between the two machines gave Advance more production and scheduling flexibility as well as capacity in its growing Swiss department.

An additional flexibility benefit for Advance is that its two Sprint 20-8 machines are convertible. In other words, they can run with a guide bushing or in a chucker mode, without the guide bushing.

“Most of the work we ran initially on the Sprints was chucker-type parts,” Mr. Dunaway says. “With parts that don’t have the length-to-diameter requirements for guide bushing support, having the option to run without offers significant savings on production runs.”

Without the close tolerance setup of the guide bushing, barstock doesn’t need to be ground and allows the shop to run cold-finished bar and tubing in the chucker mode. Additionally, there is no need to set the guide bushing, saving setup time. The remnants (80 mm) are shorter, so there is less waste on the chucker setup compared with 240 mm in Swiss mode.

Having the convertible option not only helps Advance process its parts in the most efficient way; it provides the flexibility to run in either mode, which increases the number and kinds of parts the shop can bid on. 

Shifting Gears—a Little

Advance’s next addition to its Swiss department was a DMG MORI Speed 20-11. The shop now has two.

“The Speed machines are Swiss only,” Mr. Dunaway says. “They don’t have the convertible guide bushing feature. However, as our volumes have increased, having the efficiency of a third gang tool slide and three Y axes, which these machines have, being able to have three tools in the cut at one time reduces our cycle times for longer runs. Plus, there is additional milling capability for more complex part geometries.”

The ability to bring an extra gang slide makes processing some of the materials used on the Speed, such as 1505 and 4031 stainless more efficient. Using a pinch turn or pinch milling method for better cutting and getting extra support from the guide bushing helps, too. “It is nasty material to machine,” Mr. Dunaway says. “Likewise, we run quite a bit of hardened material (through hardened 40-45 Rc) across these machines for the same reasons. Pre-hardened materials have become a specialty for us.”  

Choices

Currently, Advance has four Swiss-type machines in its stable. Two Sprint 20-8 and two Speed 20-11 machines. Having only owned these machines for 2 years, Mr. Dunaway and his operators have managed to become fairly savvy about using the attributes of each model when assigning jobs to them.

One example Mr. Dunaway cites was the first part run on the Speed. “The first part we ran across the Speed was an existing stainless job we processed in three operations using our Sprint and then finished up on one of our vertical machining centers. The cycle time using the two machines, with handling, was 22 minutes. We then tried it on our first Speed machine, and we were able to run it complete on the Speed in 7.5 minutes.”

What they have learned from working with these two models is that the Speed will provide 20 percent more efficiency over the Sprint when there is significant milling required for more complex parts. The key difference is the Speed machine’s ability to bring three tools into the cut simultaneously. However, it takes the right application to take advantage of the additional efficiency.

“We run a variety of parts in the Swiss department, so we sat down and looked at various prints to determine which machine to assign them to,” Mr. Dunaway says. “The idea was to try and optimize the production in order to provide the best value for the customer in order to win more work. Having a choice between the Sprint, with its ability to run with or without a guide bushing, and the Speed, with a third tool slide, Y axis and milling capability lets us better match the job with the tool to provide the best economies for the customer.”

Zero to 40 in 2 Years

As the Swiss department has grown at Advance, new market opportunities have opened for the shop. Medical, packaging, high pressure hydraulics and work from the fastener industry has found its way into the customer base.

“The markets seem to be finding us,” Mr. Hamilton says. “With a diversified base of customers and our increasing production flexibility, we manage to weather some of the up and down cycles of manufacturing and as a consequence, stay busy.”

Adding Swiss machining capability to its operational capability has been a boon to Advance. According to Mr. Hamilton, “Swiss machining now represents 40 percent of the company’s revenue. That additional business has occurred in only 2 years from a standing start. It’s about creating a support structure willing to look at new ways to move the business forward and finding the talent to make it happen. It’s working for us.”