Sidewall Precision

One aspect of metal cutting that has been missing from woodworking is the precision and accuracy of the shape and size of a finished part. At the heart of the problem lie the distorting effects of the grain of the wood and the inconstant density encountered as the cutter moves through the material. Wood, even hardwood, is a compliant media that tends to press away from a cutting edge and then swell back into place after the edge has passed. As a result, pockets tend to be smaller than expected and sidewalls end up in the wrong place. Efforts to overcome this tendency by increasing the attack angle and sharpness of the cutting edge, often result in a cutter that pulls into the wood, creating pockets that are bigger than desired. Making matters still worse, a poor match between the shape of the cutting edge and hardness of the wood can result in the grain being ripped apart instead cleanly cut.