Precessional Drilling and Reaming

Abstract

This document provides novel drills and/or reamers that are well-suited for making holes in a variety of materials including, but not limited to, metals, ceramics, glass, wood, plasterboard, plastics, stone, composites, synthetics, silicon or multi-layered or hybridized substrates. In some embodiments, these drilling devices have some centers of mass that are offset from the axis of rotation. Accordingly, such drills and/or reamers may rotate and cut using a precessional pattern of motion. Precessional cutting devices may display a mechanical wave pattern in relationship to the longitudinal axis of the device. If the cutting device is fabricated from a flexible material, for example Nickel-Titanium, bodily deflection of the device may result during rotation.

What is claimed is: 
     
         1 . A cutting instrument, comprising:
 a shank configured to be releasably attachable to a motor to rotate the cutting instrument about an axis of rotation; and   a drill body extending from the shank, the drill body including a shank end where the drill body extends from the shank and a free end at an end of the drill body that is opposite of the shank end, the drill body including a cutting portion between the shank end and the free end, the drill body comprising a plurality of transverse cross-sections, each transverse cross-section of the drill body having a center of mass, the drill body having a center of mass path that is defined by the centers of mass of all transverse cross-sections of the body, wherein a center of mass of a transverse cross-section at the shank end is offset from the axis of rotation, and a center of mass of a transverse cross-section at the free end lies on or near the axis of rotation.