A CMM calibration sphere needs to be calibrated on a yearly basis? This is a question that has arisen a few times here at my location. We even asked a customer's auditor and he wasn't sure himself. The CMM is calibrated yearly, but does the sphere on which its styli are qualified need calibration as well?
Actually , you don`t need calibrate the sphere every year cause only little change was taken place and the error can be ignored . You just make sure the daily maintenance when the sphere is used . and most state metrology have no ability !