A process for skiving a substrate is described, wherein the substrate is skived with a roller or a device or apparatus including the roller. The sheet material is disposed between a nose and a die of fastening apparatus. The detection server includes an image filter which carries out a working process for the image, and a detection engine which receives the image after the working process by the image filter as an input thereto and detects whether or not the image includes an object. By comparing the measured value of the torsional mechanical property to that of a baseline known to correlate to the desired target specification, it may be determined whether the diamond particles are within an acceptable range relative to the target specification.