Four Plane Facet Point Drills — Basic Design and Cutting Model Predictions

doi:10.1016/S0007-8506(07)60999-8

CIRP Annals

Volume 39, Issue 1, 1990, Pages 41-45

https://doi.org/10.1016/S0007-8506(07)60999-8 Get rights and content

The Four Plane Facet Point drill popularly favoured for NC/CNC applications but seldom analysed in the research literature is investigated.

A detailed analytical study of the design geometry, specification, point sharpening and predictive mechanics of cutting models for thrust, torque and power is presented. While the preferred method of specification for the “general” Facet Point geometry requires seven drill point features. six of which are commonly used in general purpose drill specifications, the “special” Facet Point design with the seventh feature set to zero degrees is proved to be the superior Facet Point design on the basis of point sharpening and drill performance criteria. The predictive cutting model has been verified through a comprehensive experimental investigation and a computer module for Facet Point drills added to the CAD/CAM software reported in earlier papers. It is significant to note that a brief comparison of facet point and general purpose drill designs has not supported the claimed superiority of the Facet Point drill over the general purpose drill.

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Four Plane Facet Point Drills — Basic Design and Cutting Model Predictions

A. Int. J. Mach. Tool Des.

Annals CIRP

Int. J. Mach. Tool Des. Res.

Performance of Metal-Cutting Tools

Tool Design

The Machining of Metals

A.S.T.M.E. Tool Engineers Handbook