Redefining High Speed Machining

This is a completely new method of machining," says Glenn Coleman, vice president of product design at Surfware Inc., Westlake Village, Calif. He's describing TrueMill, a new tool path technology in the latest version of the company's SURFCAM Velocity Computer-Aided-Manufacturing (CAM) software. The result: The new version offers a four to six-fold increase in machining productivity, says Tom Bentley, president of Programming Plus Inc., a New Berlin, Wis., dealer in CAD/CAM solutions.

Bentley says Surfware's idea, now being patented, boils down to a fundamental rethinking of CAM software. "Adopting a 'clean sheet' approach, Surfware's design strategy is to have the software determine tool paths for optimal feed rates." The secret, says Bentley, is Surfware's software algorithms that generate the optimum tool engagement -- thus stabilizing the load on the tool. "By knowing that the tool load won't exceed a certain amount per pass, the feed rate is easily optimized at a surprisingly high level. In traditional approaches, where there is no tool path management, the resulting variability in the tool load is typically resolved by running at a low, non-optimum level."

Tool paths (top) reveal how TrueMill uniquely generates a milling solution specific to each task. With traditional CAM, part geometry drives the tool paths (bottom).

TrueMill's heightened feed rate and enhanced cycle times have other benefits, Bentley says. Reduced tool wear is one example. "If my cutter goes six times faster, I get out of the cut quicker, and the cutter is only engaged one-sixth of the time. As a result, tool wear is proportionately reduced."

With tool wear, the time engaged in the cut is more significant than the feed rate, he explains. In addition, production goals can be met with less wear of the machine tool.

Adds Coleman: "With SURFCAM Velocity, you can dynamically manage tool loads, produce smoother cuts, enhance part quality and boost productivity on any existing CNC machine. One of the most important aspects of TrueMill is its complete independence from the machining hardware, including the cutting tool, tool holder, the controller as well as the machine tool. All things being equal, TrueMill tool paths can be driven faster and deeper than other tool paths, resulting in dramatically reduced cycle times, while extending cutting tool life." Adds Bentley: "And since TrueMill manages the tool load -- by managing the tool path -- expect to go faster in the milling of virtually any material."

Surfware's TrueMill technology, available this summer for 2 1/2 axis milling, will also be included in the next revision of the company's 3 axis roughing and finishing applications.