Published 9/20/2010

Titanium Calls for a Tight Hold on the Tool

Haimer’s SafeLock System provides pull-out protection for tools in high performance cutting such as the machining of titanium.

Mark Albert

Editor Emeritus, Modern Machine Shop

This illustration identifies the main features of the system. Most important are the drive keys that interface with grooves on the tool shank that spiral in the opposite direction of tool rotation.

Haimer’s SafeLock System provides pull-out protection for tools in high performance cutting such as the machining of titanium.

Meeting the challenge of machining titanium effectively is the focus of many machine tool builders and cutting tool manufacturers. A common theme is “no missing links.” That is, a shop needs the right machine, cutting tool, programmed tool path, workholding setup and coolant delivery system to master titanium machining. Brendt Holden, president of Haimer USA (Villa Park, Illinois) would agree, except he’d add one more critical link to this chain of required elements—the right toolholder. Haimer USA’s parent company in Germany has developed a system specifically designed to address one of the problems encountered when applying high-performance cutting to titanium and other tough alloys. This system, called SafeLock, is designed to prevent a cutting tool from loosening and being pulled out of its holder. This situation could potentially scrap a very expensive aerospace part.

“When rough cutting these materials, the high forces can create a slight movement of the tool called microcreeping, which gradually loosens the tool despite the high clamping forces between the cutting tool shank and the shrink-fit toolholder chuck,” Mr. Holden explains. The SafeLock system uses drive keys built into the chuck. These drive keys interface with corresponding grooves on the shank of the cutting tool. Because the grooves run in a direction that tends to pull the tool shank into the chuck, they effectively counteract the microcreeping tendency.

Used in conjunction with properly balanced, top-quality shrink-fit tooling, this system enables cutting with the maximum forces for which the machine and cutting tool are designed, with little worry of the tool twisting out, Mr. Holden says. “In the highly competitive world of aerospace machining, no shop can afford to give up on getting the full benefit of what advanced machining and cutting tools can offer.”

Mr. Holden sees this development as part of the ongoing advancement of tooling systems for high-performance cutting by Haimer. “Our PowerShrink chucks and HeavyDuty chucks represent key breakthroughs in this progression,” Mr. Holden says. “For us, SafeLock is simply the ultimate plateau in this movement.”

The SafeLock system is being licensed to a number of cutting tool manufacturers, thus allowing them to add the modifications to the shanks of their cutting tools when customers request tools compatible with this system.