Peter Zelinski has been a writer and editor for Modern Machine Shop for more than a decade. One of the aspects of this work that he enjoys the most is visiting machining facilities to learn about the manufacturing technology, systems and strategies they have adopted, and the successes they’ve realized as a result. Pete earned his degree in mechanical engineering from the University of Cincinnati, and he first learned about machining by running and programming machine tools in a metalworking laboratory within GE Aircraft Engines. Follow Pete on Twitter at Z_Axis_MMS.
In a post on Hurco’s CNC machining blog, company applications engineer Mike Cope describes how the fixture shown above was implemented to allow a five-axis machining center to achieve not just five-sided machining for one part, but five-sided machining for all of the workpieces shown here with a single cycle.
Programming the four different pieces at these four different orientations would seem complicated, but Mr. Cope explains that it can actually be accomplished using straightforward control features. A “transform plane” function is used to relocate the program origin from the center of the workpiece to the peak at the center of the fixture, and also to tip the coordinate field to match each part’s 20-degree angle. Then, a “toolchange optimization” feature is used to allow each tool to make the relevant cuts on each of the parts before the tool is changed out. The result is five-sided machining gracefully expanded into multiple-workpiece machining.
The recent Methods open house and technical seminar event included the public premiere of its new partnership with 3D Systems. Seen here at the Methods event (the tallest machine just past the crowd) is the 3D Systems Prox300 machine for production 3D printing of dense metal parts and a selection of parts grown on the machine.
Methods Machine Tools’ “Techfest 2015” event was the public premiere of the company’s newly signed partnership with additive manufacturing technology supplier 3D Systems. Alongside its machine tool offerings from brands such as Nakamura-Tome, Kiwa, Yasda, Feeler, FANUC, Hanwa and Current EDM, Methods will now also supply 3D Systems equipment for additively producing polymer, ceramic or dense metal industrial parts.
Significantly, Methods says it will also help companies succeed with these additive technologies. In the machine tool sphere, the company aims to be a “solution” provider rather than solely an equipment provider, and it is known for turnkey installation of engineered systems combining machining technology with support equipment such as automation. Company President and CEO Bryon Deysher says the company will bring the same kind of engineering support to its sales of additive manufacturing technology.
“We are all in,” he said, describing his company’s commitment to additive manufacturing in remarks to an audience of attendees to the Techfest event. One of the challenges of additive manufacturing is that large companies can afford to invest in the learning curve necessary to succeed with additive, but small to midsize manufacturers struggle with this. He says Methods’ aim will be to fill this very gap, by staffing up with technical personnel focused on additive manufacturing who can guide customers along the way to successfully and efficiently applying this technology to industrial production.
Growing that staff will be part of Methods’ long-term investment in advancing additive technology, he says. He expects manufacturers will evaluate additive with a similarly long view. “I believe, if you are not thinking about this now, you’ll wish you were in two years,” he said at the event.
One of the company’s new hires is Benjamin Fisk. Until a couple of months ago, Fisk was a manufacturing technology manager overseeing AM efforts at Pratt & Whitney. Now, he has joined Methods as the general manager of what will eventually become a nationwide additive manufacturing team for the company, ready to support the AM efforts of companies much smaller and less well known than his former employer.
For these small and midsize manufacturers, he says, there are significant challenges today that inhibit additive manufacturing gaining ground. The burden of AM development and integration generally falls on users, he says. When it comes to development, a general lack of process knowledge leads to significant developmental costs. And when it comes integration, this effort has to be inclusive of a complete process from design through inspection.
“You can’t think about 3D printing as just a standalone process,” Fisk said.
Methods can help with this entire range of challenges, he says. The company can engineer a system for additive manufacturing that includes postprocessing equipment and other support capabilities. And it can assist customers to refine and prove out not just the additive portion of the process, but instead the entire part-making sequence including the additive step.
The Techfest event showed various equipment likely to be included in processes such as this. In a conversation with Fisk, I asked him to indicate machine tools at the event likely to be useful for processing 3D-printed metal parts. He pointed to wire EDM first, as this is frequently the best method for removing printed parts from their build platform. Next in the sequence might be a small five-axis machining center, he said—that is, a machine able to make the necessary finishing passes for the kind of geometrically intricate workpiece that additive manufacturing is able to produce.
The integration with machining is vital to success of additive manufacturing, because production AM parts almost always require machining for critical features and tolerances. Methods says an additive part-making process might include post-processing capabilities such as wire EDM (left) for cutting the part from the build platform as well as five-axis machining (right) for finishing complex forms. The company sees its ability to provide all of these capabilities—additive and subtractive—as being one of its important strengths in advancing AM.
Another capability seen at the event was robotic loading of both standalone and multiple machines. Integrating robots is a common part of Methods’ turnkey engineering. The company’s robotic installations to date have been for subtractive machine tools, but now this same kind of integration of automation might soon be applied to production processes involving additive manufacturing as well.
There was a time when EDM machine maker Chmer (Taichung City, Taiwan) might have expected high speed milling to take the place of a significant amount of die sinker EDM work. The company developed a line of high speed milling machines to complement its sinker, wire and holemaking EDM machines in anticipation of this change. But things didn’t work out that way—illustrating, among other things, how difficult it is to predict technology adoption. On a recent trip to Taiwan, I had a chance to speak about this with Chmer Marketing Director Brad Wang.
While the ability to take fast, accurate cuts at high feed rates potentially makes milling a contender for certain complex die/mold forms that sinker EDM is used to produce, EDM is still more efficient for features such as deep cavities, fins and many thin walls. These features occur just often enough that high speed milling has not been able to unseat the established technology to any considerable extent. However, high speed milling has proven popular among Chmer’s customers nevertheless, not as a replacement for EDM but as a complement. The fast, accurate cutting is efficient for roughing complex mold forms before the sinker EDM is used to complete those features that EDM is still the best at finishing.
The technology needs and preferences of customers reveal themselves over time, Mr. Wang says. His hope is for Chmer to continue to adapt. Here are the EDM features and capabilities right now that he sees as becoming increasingly important:
1. Linear Motors. Among each of the company’s EDM types (and its milling machines) are models equipped with linear motors for axis motion. Linear motor machines cost more than machines driven by ballscrews, Mr. Wang says, but these motors save cost through reduced maintenance while improving the accuracy of the machine. Compared to conventional drives, a wire EDM machine with linear motors can generate sharper corners on precise components such as die punches. More, linear motors maintain their accuracy over time. This is not the case with ballscrews, which wear and become less precise over time due to the ongoing surface-to-surface contact.
2. Machine Monitoring. Applications of EDM often involve rows of machines all running largely unattended because the cycles are so long. The unattended nature of the process makes the machines ideal for monitoring systems permitting remote viewing of the current status of the machine as well its performance history over time. Chmer’s in-house control has enabled the company to develop its own remote monitoring system, among other special features. (Read on.)
3. Ease of Use. The in-house control has also enabled Chmer to develop a programming system enabling inexperienced users to employ EDM effectively. An operator can enter the workpiece material and diameter of the wire along with the desired roughness of the machined surface to let the control automatically set the cutting conditions and parameters required.
4. Hole Making. Among the three EDM types, holemaking looks to offer the most potential for future growth, says Mr. Wang, thanks to the long-term likely demand for cooling hole machining in turbine components by the aerospace sector. Key capabilities here include precise CNC interpolation to give small holes with a diffuser (open funnel) form at the mouth, as well as integration with B-axis indexing for the array of angles characteristic of the set of holes in a typical blade.
Chmer’s AD4L is a linear-motor equipped holemaking EDM.
What is the relationship between robotic automation and employment? The relationship would seem to be an inverse one. That is, as the use of robots increases, employment should go down—or so we might expect.
A new white paper from the Association for Advancing Automation (A3) demonstrates that this expectation is false. Robots do not appear to replace employees, because the correlation between them is positive. When robot shipments have gone up, employment has gone up at the same time.
U.S. employment data compared to U.S. robot shipments show this. During periods when robot sales were increasing, employment has been generally increasing as well. The correlation was particularly apparent from 2010 to 2013, when both U.S. employment and U.S. robots sales grew steadily. (Employment then dropped a notch in 2014, while robot sales continued to grow.)
The paper also gives examples of companies that have increased both employment and the use of robots. Marlin Steel is one these. The company’s CEO, Drew Greenblatt, is quoted. “Not only has changing over to an automated production process saved our company from the threat of bankruptcy, saving the jobs of everyone here, it has allowed us to expand our work force,” he says. “Since going automated, Marlin Steel has nearly doubled the size of the work force, adding engineers and automated production specialists to our existing team.”
Those job types he mentions suggest another aspect of automation’s impact on employment that the A3 paper also addresses. Namely: The jobs added are often higher in responsibility and compensation than what was typical of the company’s workforce before it increased automation.
Robots, in fact, are helping with the need to attract talent to manufacturing. Vickers Engineering CEO Matt Tyler sees this. After his company’s shift to automation, he says, “We’re now able to attract people who aren’t just looking to draw a paycheck, they’re looking for a career.” Vickers senior automation engineer Jordan Klint adds, “In order to bring young people into the business, you have to have technology. The guys who report to me really enjoy the robotics side. They think robots are cool.”
Obtain the white paper at A3automate.org, and read further thoughts about the relationship between robots and employment here and here.
Steve Murray shows a sand mold component that would have required a complex pattern involving inserts to produce the various slots. 3D printing made this component much easier to produce.
Steve Murray, additive manufacturing consultant at Hoosier Pattern, will be one of the speakers at this month's Additive Manufacturing Conference. His company is advancing a means of making foundry molds through 3D printing that is bringing new design freedom to cast parts—read more here. The conference—October 20-21 in Knoxville, Tennessee—focuses on industrial applications of additive manufacturing. Learn more and register to attend at additiveconference.com.
And speaking of additive … have you seen the new Additive Manufacturing website? We have been posting new content here daily. The increased attention to AM extends to social media, too—join us as one of the earliest followers of Additive Manufacturing on Facebook, Twitter and LinkedIn. Also this month, AM subscribers will receive the first issue of the new, full-size Additive Manufacturing magazine. Begin a subscription here.