  We use flicker-noise spectroscopy (FNS), a phenomenological method for the
analysis of time and spatial series operating on structure functions and power
spectrum estimates, to identify and study harmful chatter vibrations in a
regenerative turning process. The 3D cutting force components experimentally
measured during stainless steel turning are analyzed, and the parameters of
their stochastic dynamics are estimated. Our analysis shows that the system
initially exhibiting regular vibrations associated with spindle rotation
becomes unstable to high-frequency noisy oscillations (chatter) at larger
cutting depths. We suggest that the chatter may be attributed to frictional
stick-and-slip interactions between the contact surfaces of cutting tool and
workpiece. We compare our findings with previously reported results obtained by
statistical, recurrence, multifractal, and wavelet methods. We discuss the
potential of FNS in monitoring the turning process in manufacturing practice.
