Measuring apparatus and instruments, namely, [ angle gauges, angle dividing apparatus, spherometers, inclinometers, interferometers, thread measures, gauge comparators, ] sensors for detecting cutting work piece references and cutting edges, [ surface roughness testers and flatness testers, sound checkers for cutting check via sounds, ] and surveying apparatus; [ system for managing cutting machine tools and holders, comprising computer hardware, sensors, computer software for identifying int...