Software optional: 5-Axis Machining

Debating the need for CAM systems on Swiss-style machines.

As CNC machine tools become increasingly complex, so does the job of programming them. CNC Swiss-style machines are no exception. With more tools than the Snap-On truck and tighter quarters than a World War II submarine, many shops view them as coding nightmares.

Yet the bane of these machines—their complexity—is often a boon. With stations aplenty, it’s likely that some of the needed tools already reside in one of the machine’s many turrets or slides, reducing setup time. Because the parts made on a Swiss-style machine are relatively small, stock removal is minimal—program a single pass and you’re done. And Swiss-style machine builders have incorporated cool features, such as synchronization codes and automatic axis mirroring into their machine controls, simplifying manual programming.

Courtesy of Marubeni Citizen-Cincom

With seven cutting axes and up to 32 tools, the L20E Swiss-style machine from Marubeni Citizen-Cincom might be a challenge to program manually.

An experienced Swiss setup person can often program at the machine and have the first part in inspection faster than programming it in a CAM system, according to Brian Such, an Elk Grove Village, Ill.-based customer support group manager for machine builder Marubeni Citizen-Cincom Inc., Allendale, N.J. “In many shops, the parts are pretty straightforward, so programming means turn, drill and cut off,” he said. “It’s not that difficult.”

Despite his hands-on perspective, Such warned that traditional programming tasks are changing. As shops become more diverse in terms of machine capability, manual programming methods may be going the way of paper tape.

“The whole world wants to go CAM, and our customers are increasingly looking for people who can go cross-platform,” Such said. This means some underpaid soul has to program Swiss-style machines one day, wire EDMs the next and 5-axis machining centers after that. Programmers often multitask more than the machine tools they program.

Send in the CAMs

Someone who’s participated in the evolution of Swiss programming is Don Davies, director of sales and application engineering for DP Technology Corp. He admitted that a seasoned setup person might be able to whip out a manual program quickly, but stated that CAM systems offer benefits beyond just code generation. Multitask machines in general require synchronization, and Swiss-style machines are the mothers of multitasking. And simulating machine movements before the first chips fly can cut setup time and avoid costly crashes.

Davies said, “Even on parts that are simple to program, simulating the machine setup—seeing axis movements, how the tools are plugged in and if there are any potential violations—can be very valuable.”

DP Technology Corp., Camarillo, Calif., has been developing ESPRIT CAM software for Swiss-style machines since the mid-1990s. Twenty years ago, shops were still seeing orders for a gazillion parts, and setup time wasn’t a huge concern. But the market has changed.

“Today, you see orders of 50 parts and they’re (often) far more complex than 20 years ago,” Davies said. “That combination means you need a CAM system to stay competitive.” DP Technology serves this market with its ESPRIT CAM product, with features such as B-axis support, G-code optimization, pinch milling and several flavors of axis synchronization.

Good functionality is important, but one of the most important attributes of any CAM system is its post-processor. “We’re talking about the engine,” Davies said. “It sits within the CAM software, building the code and performing the synchronization and process planning. Regardless of the operations you’re going to perform on the Swiss machine, the post has to handle them. The goal is to push a button and see G code, with no edits required. It’s not simple.”

Courtesy of DP Technology

DP Technology’s ESPRIT CAM software shows three-channel simultaneous simulation of a rifle bolt carrier being machined on a Citizen M32 Swiss-style machine.

To that end, DP Technology offers post-processors for all major brands of Swiss-style machines in all their various configurations. Yet Davies said machine builders are busy dreaming up even better mousetraps. “I’m hearing noises that they’re planning to release even more complex machines.”

This doesn’t necessarily mean more axes or more tools, but more capability. One example of this is simultaneous 5-axis machining. Where 3-axis milling on a Swiss-style machine was unusual just a few years ago, builders have introduced 5-axis milling capability. “Who knows what the future’s going to be?” Davies asked.

David Green, manufacturing engineer at FMI Hansa Medical Products LLC, Madison, Ala., has been using ESPRIT since 2007. The shop manufactures a variety of bone screws, dental implants and cardiovascular components in titanium and cobalt-chrome alloys. With 10 Swiss-style machines to manage, the largest of which is a 7-axis, 32mm machine, Green is busy.

“Before ESPRIT, we would key in all the programs by hand,” Green said. “This isn’t as complicated as you might think, because you can program one axis at a time and use the built-in synch codes to marry the different axes. But still, it would take us an hour or two to enter each program and debug it.”

FMI Hansa’s work has evolved since 2007. Not only are there more machines to program, but the parts have become more challenging. That’s because the shop’s CAM system has created new business opportunities by allowing it to take full advantage of the Swiss machines’ multiaxis capabilities. Where manual programming methods once limited them to 2-D features, they are now able to generate complex geometries with 3-D sculpting and 4-axis simultaneous cutting.

“Obviously, we couldn’t make those kinds of parts before,” Green said. “And with the programming now done offline, machine output has increased. We don’t have to stand in front of the machine for hours at a time, keying in code. Now, the setup technician pulls the program in via Ethernet and it’s basically ready to run. Looking back, I’d say we were really limiting ourselves with manual programming.”

Chicken or the Egg?

Someone who agrees wholeheartedly with that opinion is Gary Hargreaves, vice president of business development for CNC Software Inc., Tolland, Conn., the developer of Mastercam. A relative newcomer to the Swiss market, CNC Software entered the fray in 2010 by acquiring the assets of Jurasoft SA, a Switzerland-based company known for its Swiss-specific CAM system, SylvieXpert.

Courtesy of CNC Software

A representation of multiaxis machining with Mastercam Swiss Expert’s built-in simulation capability.