Since John Bosch edited and published the first version of this book in 1995, the world of manufacturing and coordinate measuring machines (CMMs) and coordinate measuring systems (CMSs) has changed considerably. However, the basic physics of the machines has not changed in essence but have become more deeply understood. Completely revised and updat

This book is a printed edition of the Special Issue "Design and Applications of Coordinate Measuring Machines" that was published in Applied Sciences

The purpose of this paper is to relate some of the experiences of using a coordinate measuring machine (CMM) to calibrate long end standards and step gages at measurement uncertainties of less than 0. 5[mu]m. It is not the intent of this paper to suggest that everyone should return to his or her laboratory and change the way CMMs are operated nor to suggest that the methods discussed here are even the best methods. The intent is to provide some food for thought, based on real experiences, about the use of a CMM to measure at low levels of uncertainty. As will become apparent, a lot of the issues discussed really apply to any dimensional measuring technique operating at low levels of uncertainty, not just a CMM. The discussion in this paper is based on measuring one-dimensional end standards and step gages placed along the x-axis of the Moore M-60 CMM located at the Oak Ridge Metrology Center, which is part of the Oak Ridge Centers for Manufacturing Technology at the Y-12 Plant (formerly used in manufacturing nuclear weapons parts) in Oak Ridge, Tennessee. When the Cold War ended, the U.S. Department of Energy (DOE) pushed to make nuclear weapons technology available to U.S. industry. As part of this technology transfer effort, it was determined that the M-60 could be used by the National Institute of Standards and Technology (NIST) to provide a calibration service for step gages. Previously, U.S. industrialists had to go to Germany for step gage calibrations at the lowest levels of measurement uncertainty. Much of the discussion that follows is based on the process developed to use the M-60 for the NIST calibration.