Chatter Vibration in Drilling

Abstract

Chatter vibration of long drills has been investigated using several drills with different overhang lengths and special drills with different pieces of additional mass. The frequency, amplitude, initiation boundary, and unstable range of chatter vibration were measured at various cutting parameters. The experimental results showed that the vibration is a regenerative chatter and its frequency is equal to the bending natural frequency of the drill when the drill point is supported in a machined hole. Based upon the experimental results, the stability of chatter vibration was discussed. It was clarified that unstable ranges appear only when the chatter frequency in one workpiece rotation is an odd number.