Measuring Screw Threads: New Technologies and Old Standards

In the last five years, advances in laser technology and decreases in the cost of laser sensors and high precision motion systems have made it feasible to develop a laser-based product for measuring the geometry of screw threads. The operating principles of such a system will be described. A significant issue in the development of the system was the interpretation of thread dimensional standards which were written with contact gaging in mind. A second issue has been establishing correlations with other thread gaging methods, given the absence of master and grandmaster threaded artifacts.