Rick Richardson
Owner
QA Productivity Systems

After spending twelve years in the electrical field in sales, marketing and international areas with Thomas & Betts and AMP, Inc., Rick Richardson, has spent over thirty years in the metrology field  in various sales and marketing capacities with Hansford Mfg., Hansford Data Systems, and as the owner of QA Productivity Systems, a marketing firm specializing in CMMs, vision metrology, lasers, and systems dealing with surface roughness, flatness, roundness, and machine tool alignment.  Mr. Richardson was a member of the first ASME, B89 Committee in 1978 dealing with CMM national specifications. He has presented at SME Conferences and written articles on CMM calibration techniques.

PRESENTATION: Verifying the Accuracy of CMMs Between Calibrations
How does the user know the measuring accuracy of a CMM between yearly calibrations?  CMM calibration by either the OEM manufacturer or an independent service provider on an annual basis gives the user a calibration sticker and report, but how does the user know from day to day, week to week and month to month the measuring accuracy of his CMM?  

To fill this void, the use of calibrated traceable artifacts such as gage blocks when used with a disciplined protocol is one answer for establishing verification of calibration on a day to day, week to week and month to month basis for small to medium sized CMMs.  With greater knowledge gained by more frequent verification of CMM calibration, better utilization of CMMs can be achieved leading to more efficient machine scheduling, reduction in scrap, and less chance of out of tolerance material getting into the supplier chain.

This paper will outline how the use of gage blocks with simple holding devices and efficient records can establish quick verification of CMM calibration accuracy values between yearly calibration.