Spinning Turning Tool Offers Alternative To Single-Point Cutters

CAM developer DP Technology recently performed a successful test cut of a new cutting tool for turning applications that is designed to reduce vibration and heat buildup. The company's CAM software package, Esprit, now contains an add-on for programming the new tool.

Developed jointly by machine tool builder Mori Seiki and cutting tool manufacturer Kennametal, the turning spinning tool is designed to distribute heat and wear more effectively than a single-point lathe cutter. It employs a specialized insert, which is similar in design to a round, or full-radius, insert, and it is mounted at the bottom of a cylindrical tool shank held in a rotary spindle.

Olivier Thenoz, mill-turn product manager at DP Technology, teamed up with Nitin Chaphalker, engineering team leader for Mori Seiki's Machining Technology Laboratory, (MTL), to perform the test cut. Performed on steel workpiece mounted on a Mori Seiki NT4200, the test included roughing and finishing operations with OD passes on straights, tapers and arcs without the use of coolant.

"The advantage of the spinning tool is that there is no single point that is in contact with the workpiece all the time, and this is very good for heat dissipation and tool wear," Mr. Thenoz says. "Cutting conditions are no longer limited by the heat generated in the process, but by the power available in the machine."

Mr. Chaphalker adds that axially loaded tools such as the spinning tool direct most of the cutting forces axially into the spindle, reducing vibration and chatter. In contrast, cutting forces generated by single-point cutters impart a bending movement on the tool and cause vibration.

For the initial OD rough cut, the spinning tool was inclined at a 20-degree angle to allow effective heat evacuation. The turning spinning was also said to perform admirably when tested on taper and arc moves that required back-and-forth motion. It remained close to the material throughout the cut without requiring the repositioning moves necessary when using single-point tools cutting in a single direction.