Aerospace machining has long been an experienced-based industry. If a problem occurs, the standard response is to decrease the speed and back off the depth of cut. So, the end result is that, while the part is eventually correct, no knowledge is gained from the process. An opportunity to gain additional information in order to improve the efficiency of the process has been lost.

According to Jerry Halley, considered by many to be an innovator of high-speed machining in aerospace, machining needs to become less of an art and more of a science. Halley, an associate technical fellow at Boeing Aircraft and Missiles Division in St. Louis, believes that in order to improve the industry, machining should avoid the trial and error process by being more deterministic and less of a craft or trade.

"If you don't know the correct measurement, it's a guessing game to find optimum machine performance," Halley says.

By making measurements such as a frequency response function, it is possible to characterize the performance of the tool tip very effectively and to ultimately have the ability to understand how the tool is going to cut before the machine is turned on. Armed with this knowledge, machining becomes much more of a deterministic process rather than a guessing game.

One component of understanding the science of machining is to strive for the same tool performance wherever the machine is and whatever the conditions the machine is under. This is not so much a question of the machines' capability but of operator education and shop culture, says Halley. "It is an issue of user execution. We are not yet close to standardizing this. In terms of the capabilities of the machines, it is there for the taking. The question becomes one of discipline and how you control the tool, the tool holder and the process parameters."

Another rapidly changing area involves helping others realize the proper use of a machine when outsourcing. While there are obvious financial advantages, the key to outsourcing successfully is to ensure that the quality of the product will not be affected. According to Halley, an effective way to do this is through sharing technology.

Machining is still a craft-oriented industry. Understanding more about running a machine at an optimum level, maintaining an industry-standard for tool use and performance and finding cost-efficient methods of production while maintaining quality—such as outsourcing—are ways to transform machining into a science.

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