We all know that every CMM has a manufacturer stated accuracy and repeatability. We also all know that the procedures used to establish these numbers are performed using very specific hardware and programs. I want to establish a capability based on what we are using in the real world.
My idea is to use an artifact with known values and using the hardware that is currently utilized on the CMM, perform a repeatability study and calculate the standard deviation of each combination of hardware (probe). Calculate the 3 sigma limits of each combination and use the highest value to compare to my part tolerances to establish capability.
Does anyone have an opinion or method they currently use to evaluate capability? I understand that a gage R&R will tell me if the CMM can repeat and reproduce the measurement as compared to part tolerance however this doesn't take into account the accuracy of the measurement.
Or have I just been looking at numbers too long...
