A Basic Correction to the Orthogonal Metal Cutting Models

Metal cutting as a science remains more art than science. A truly predictive model for use in quantitative modeling has eluded researchers to date, leading the noted mathematician, R. Hill [1] to observe that “it is notorious that the extant theories of the mechanics of machining do not agree well with experiment”. Extensive experiments with a videographic quick stop device (VQSD) by the author indicate an extremely simple reason for these disagreements. A simple correction that is applicable to all of the classic orthogonal models of metal cutting is presented. A detailed application to the classic Merchant Force Diagram is then developed.