Switching from Solid Carbide to Indexable Tooling Permits Lights Out Mold Base Manufacturing

Since 1965, Craftsman Tool & Mold has specialized in creating large, close tolerance, complex, high precision, custom mold bases for the aerospace/defense, appliance, automotive, computer/business equipment, electronics/electrical, hydraulic/pneumatic/controls, lawn and garden, medical/optical/dental, telecommunications, toys/recreational/sporting goods industries. Its 50-person team focuses mainly on stack mold bases and rotational spin stack mold bases for the multi-shot plastic injection mold industry across North and South America. Other services include large-capacity gun drilling, grinding, CNC milling, die sets, bolster plates, and specialty machining.

According to Jason Long, Craftsman Tool & Mold product manager, the team needed a solution to create small, deep pockets in its large mold bases. They were using solid carbide mills, which resulted in repeated breakage issues.  On top of that, given the unreliability of the cutters, Long was extremely reluctant to allow unattended machining. The shop always had an operator at the machine to monitor progress, adding an expense for each project.

Tungaloy Sales Engineer Connor Hartigan worked with Long to find a solution to the breakage problem. First, they tested the Tungaloy TungForceFeed indexable tools in both a ½” and 3/8” size.

TungForceFeed is a small-diameter indexable high-feed milling cutter with a robust design for stability and efficiency, available in as small as ø.375 (8 mm) in diameter. It offers free cutting and effective chip control in a wide range of applications. Designed with a small entry angle for stability, TungForceFeed inserts improve efficiency by reducing chatter and increasing tool life when machining in standard and long reach areas. “The fact that the tool is in and out of the cut faster improves both productivity and tool life,” Long says.

The key is the way the tool forms small chips and throws them out of the pocket. The positive cutting-edge position contributes to a controlled chip formation and good chip evacuation when machining slots and pockets. This proper chip control eliminates re-cutting and premature insert failure.

Tungaloy increased the insert screw size to add more shear resistance and ease insert mounting; designed a more robust insert edge and geometry for better chip evacuation and reduced insert fracture to lengthen cutter life.

After testing, Craftsman gained confidence in the process enough to allow unattended overnight machining and improved efficiency and reliability just by making the switch from solid carbide to indexable tooling.

Before TungForceFeed, cutting small, deep pockets in its large mold bases would take hours to machine due to changing inserts/endmills and limited operator availability. With TungForceFeed, Craftsman can machine the same number of pockets twice as fast and on the off shifts unsupervised, resulting in greater throughput running upwards of 700 sfm at 300 ipm.

“Not only did the TungForceFeed increase efficiency by 27 percent, but it eliminated the breakage issue completely,” Long says. “This tool’s stability improved productivity during the day and gave us the confidence to run lights out.”