The use of solid ceramic end mills is on the rise, says Thilo Mueller, manager of solid end milling tools with Kennametal. And in a way, that news is less dramatic than it might sound, because solid ceramic end mills are arguably easier to use than carbide ones. Shops applying them need not make special process changes. Contrary to what is often assumed about ceramic tooling, these end mills do not require runout any better than what is used for comparable carbide tools. And because the tools perform effectively when machining dry, considerations related to coolant become irrelevant.
All the tools really need is speed, he says. They employ heat as part of their cutting mechanism—the heat that comes from fast, dry cutting, the same heat that might be destructive to other tools. The best performance with a ceramic end mill generally occurs in a dry machining application in the range of 3,000 to 4,000 sfm.
Posted by: Jedd Cole 22. February 2017
Posted by: Derek Korn 21. February 2017
Current trends in machine-tending robot technology include collaborative robotics, in which a human can safely work near a robot without conventional fencing; easier deployment of robots to different machine tools when necessary; and simplified programming.
The Robo2Go machine-tending system from DMG MORI Systems leverages technologies that address each of these trends. It is particularly well-suited for shops that run a variety of different jobs, but would like to reap the benefits of unattended or lights-out machining on its DMG MORI turning centers that feature the company’s CELOS control.
Posted by: Stephanie Hendrixson 20. February 2017
One pitfall in implementing metal additive manufacturing is to think of metal AM in terms of CNC machining. Doing so can set unreasonable expectations in terms of productivity. Even more dangerous, however, is to treat AM equipment like CNC machine tools in terms of safety.
“Believe it or not, companies are not being safe,” explains Ed Tackett, director of educational programs at UL's Additive Manufacturing Competency Center (AMCC). The UL AMCC takes a safety-first approach to all aspects of metal additive manufacturing, teaching students how to identify risks—material behavior, health risks, waste management—and then mitigate those risks. Read the full story in the February issue of Additive Manufacturing magazine, beginning on page 26.
There’s good reason why subspindle-equipped turning centers, particularly Swiss-type lathes, are so popular for small, complex parts produced in high volumes. However, there’s also good reason for the prefix “sub.” Automatic part hand-off for backworking operations isn’t viable without secure gripping, and the smaller, already-machined portion of the work presented to the subspindle tends to create more challenges than the raw barstock gripped in the main spindle. As a result, subspindles can be limited when it comes to blind-hole broaching, heavy peck drilling and other processes that risk pushing a part off-kilter or damaging it.
However, the right workholding can break down these barriers, says Matt Saccomanno, CEO of Masa Tool (Oceanside, California). Founded in the wake of Mr. Saccomanno’s own frustration with secondary operations and underutilization of subpsindles, Masa Tool offers the Microconic system, an alternative to traditional, extended-nose collet designs that applies force closer to the part for greater rigidity and concentricity—advantages that extend to main-spindle operations as well. Another benefit is the ability to adjust clamping pressure at the spindle nose to grip securely without damaging small, fragile workpieces. On the efficiency front, a collet in one size can be swapped for another without reaching anywhere beyond the spindle nose, and any collet can fit multiple draw-type or push-type machine collet closers. This saves time and eliminates the need for different collet series for different machines. Finally, overgrip models that expand 0.157 inch (4 mm) beyond the clamping diameter enable reaching over and gripping the part behind large-diameter areas.