What Your Handbook Isn’t Telling You

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Tony Schmitz, professor at the University of North Carolina at Charlotte, gives a presentation on machine tool dynamics. Learn the role that this concept plays in realizing your optimal machining center performance.


This example of a stability diagram shows how increased depths of cut that are possible within specific, narrow bands of spindle speed. Sometimes a deeper cut is possible at a higher speed than where the process is currently running.

Tony Schmitz, a professor at the University of North Carolina at Charlotte, recorded this quick presentation on machine tool dynamics. It’s worth watching—less than 12 minutes long, with a quiz at the end to make sure you got the key points. If you understand that vibrations are a major contributor to the performance of your machining process, but don’t quite know how to put this understanding to practical use, then this presentation is where to begin. Here are two points Dr. Schmitz makes:

 The best-performing speeds for a given machining process often do not correspond to machining handbook values.

 Your process might actually deliver better tool life, surface finish and/or metal removal rate if you increase the speed rather than reduce it.

After watching Dr. Schmitz’s presentation, see an example of turning up the speed in this video, and read about how one shop is applying this phenomenon to realize the most efficient performance from its own machine tools. 


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