Linear Sawing Apparatus and its Evaluation for Research Into High Speed Bone Sawing

Abstract

Previous research into the cutting mechanics of bone sawing has been primarily approached from the perspective of orthogonal metal machining with a single edge cutting tool. This was a natural progression from the larger body of knowledge on the mechanics of metal cutting. However, there are significant differences between typical orthogonal metal cutting parameters and those encountered in bone sawing, such as anisotropic material behavior, depth of cut on the order of cutting edge radius, chip formation mechanism in the context of a saw blade kerf, non-orthogonal considerations of set saw blade teeth, and cutting speed to name a few. In the present study, an attempt is made to overcome these shortcomings by employing a unique sawing fixture, developed to establish cutting speeds equivalent to those of typical sagittal saws used in orthopaedic procedures. The apparatus was developed for research into bone sawing mechanics and is not intended to be a commercial sawing machine. The sawing fixture incorporates the cutting speed possible with lathe operations, as well as the linear cutting capabilities of a milling machine. Depths of cut are on the same order of magnitude as the cutting edge radius typical to saw blade teeth. Initial measurements of cutting and thrust force, obtained with this new experimental equipment, are compared to previous work.