Manufacturers are gravitating toward indexable tools to avert recent steep price increases in carbide tooling, says Chuck Elder, executive vice president at Ingersoll Cutting Tools, a company that supplies both types of tools. He bases his comment on information from supply-chain managers, distributors and his company's own sales figures.
Tungsten carbide prices rose five-fold in 2004, driving up the cost of solid-carbide tooling 70 percent. Prices for indexable tooling, by contrast, remained relatively stable since those tools contain only 10 to 15 percent of tungsten carbide. This carbide price run-up reduced the premium for indexable over solid-carbide milling cutters from about 50 to 20 percent, and for indexable drills, which generally cost less than solid carbide even before the run-up, the differential increased from about 30 to 50 percent.
Elder says that although carbide prices may flatten going forward or retreat slightly, the odds of any return to near pre-2004 prices are remote in the extreme. And he points out that at present carbide prices, North American manufacturers could save about $300 million a year in tooling costs alone by converting from solid-carbide to indexable round tools, and that doesn't include savings from eliminating the tool-reconditioning merry-go-round (the 4 to 15 week turnaround cycle reconditioning solid-carbide tools) and from gains in throughput.
Indexable milling cutters are growing in popularity, especially for mixed work, since several different cutting-edge types mount on the same steel shank. Opening large holes by corkscrew milling, says Mike Dieken, Ingersoll Chip Surfer product manager, is also proving a principal application and an alternative to step-up drilling because shops get away with using fewer tools.
Improved repeatability is another contributing factor in the growing trend of indexable tools. Today's indexables, according to Elder, routinely hold the same 0.0005-in. repeatability (after indexing) of any mainstream solid-carbide tool. In addition, it is possible to create better cutting geometries in an indexable insert than in a full-length solid-carbide round, he says. (www.ingersoll-imc.com)