3 Cutting Tool Advances in Electric Vehicle Manufacturing

Cutting More Freely

Mike Hafke sees much the same thing. The vice president of sales and marketing at Guhring says there are far fewer parts in an electric vehicle compared with an internal combustion engine vehicle and automakers, therefore, require fewer cutting tools. The tools they do need, however, are sometimes large and bulky but must cut efficiently. Hafke, like Kennametal’s Kurth, suggests that 3D-printed cutter bodies are becoming fairly common, and that PCD inserts continue to play an important role.

“The automotive OEMs [original equipment manufacturers] and their tier suppliers obviously own a lot of machine tools geared toward traditional components, and rather than replacing all that equipment, they’re very intent on repurposing it,” Hafke says. “Unfortunately, many of these are lighter duty machines, so we find it’s necessary to lightweight the tooling by 3D printing the cutter body or using carbon fiber. Not having enough power can also be an issue, so PCD is practically a must, but the geometries must often be modified to further reduce cutting forces. Whatever we can do to get the weight out of the tools and make them cut freely.”

Read more: Automotive Industry Trends: 3 Things to Watch for in Electric Car Manufacturing

In one example, Guhring was asked for help with an 11-millimeter-wide slotting application that had a substantial overhang on a machining center with an HSK 63 spindle, resulting in chatter and tool deflection. The solution was to reduce the cutting forces as much as possible by using positive rake PCD inserts split into two 6-millimeter-long segments and then eliminate any remaining vibration by installing an oil-encased damping element inside the tool shank.

The battery housing is another common EV component. Hafke explains that although the pockets holding the hundreds of individual cells need little machining, each has mounting points or holes for wiring that must be drilled and sometimes tapped. Right-angle attachments are required here, but the extremely long overhangs and slender tool design make it challenging to meet positional and diametrical tolerances. Once again, Guhring made special modifications to meet that challenge. “Situations like these are fairly common in the EV environment,” Hafke says.

Faster Production

OSG is also heavy in the EV market, notes product manager Kyle Matsumoto, who claims that battery housing holes can be drilled and tapped in a single operation using one of the company’s AT-2 R-SPEC thread mills. “Multipurpose cutting tools are common in the automotive industry, as they dramatically reduce cycle time,” he says. “This is just as important with electric vehicles as those using internal combustion engines.”

Matsumoto lists several additional tools popular with EV automakers: the TRA-HO 3-flute drill and a pair of cutting end mills: the AE-VTS and AE-TL-N. All have diamond-like carbon (DLC) coatings, and all are designed for nonferrous materials. “We’re also seeing increased use of carbon fiber composites, fiberglass and metal hybrid materials,” he says. “Each of these requires solutions not unlike those developed for the aerospace industry over the past decade or so.”

OSG applications engineering manager Jeff Stephens adds to the discussion, stating that the gear manufacturing process is also changing, although this is due more to new machine technology than the growth of electric vehicles. “Companies like DMG Mori and Mazak have introduced skiving and hobbing capabilities to their multitasking lathes, which is opening up opportunities for some of the tier suppliers who might not have dedicated gear-making equipment,” he says. “We support these customers as well with special cutters that bring a lot of flexibility to their operations.”

Which of the above EV cutting tool advances does your facility need the most? Let us know in the comments below.