A technique for field measurement of knife sharpness

Knife sharpness can affect the productivity of meatpacking operations as well as the forces to which meat cutters are exposed. This report describes the development and evaluation of a “sharpness tester” designed to meet the criteria that the system be portable for field use at meatpacking plants, requires no special skills to operate, provides a non-destructive test of the entire blade edge, and incorporates a test motion that is representative of meat cutting. The system was bench tested for sensitivity to incremental changes in blade sharpness; suitability of the test material as a surrogate for red meat; and ability to detect variations in sharpness along the length of the blade. A graphical presentation showed that changes in cutting forces measured with the system correspond to changes in blade sharpness. Measurements made with both the test material and with red meat showed good correlation (r=0.89). The system demonstrated the capacity to detect differences in sharpness in regions of a knife edge as well as providing visual evidence of defects along the edge of a knife blade.