On–machine Measurement of Diameter and Run–out in Axial Direction for Small Diameter End–mill in High–speed Rotation

Abstract

It is difficult to identify center axis of non–cylindrical cutting tools such as end–mill and drill because of their complicated shape and geometry. As they are attached to machine tool spindle unit with a mechanical chuck, some eccentricity arises in cutting. The rotational eccentricity of cutting tool may affect the machined surface and unfavorable surface texture is generated. It is preferable to keep the eccentricity within an allowable range so that we could achieve high quality cutting. We used a commercially available optical measuring instrument for measuring the diameter and run–out of those non–cylindrical cutting tools. In this report we describes the measuring principle and several application results. Cutter run–out as well as rotational locus in axial direction of end–mill and abnormal vibration of spindle were revealed.