In my last column I noted that I would give some hints to help you avoid problems with assigning and applying acceptance limits, so let’s go back to square one.

More companies than ever are downloading decisions to calibration laboratories causing perfectly acceptable gages and instruments to be ‘failed’ by them. How could such a thing happen?

Some of the data I’ve noted from the AMTMA studies make it very clear that measurement disputes will continue. When the range of readings is close to or exceeds the tolerances of the gages being calibrated, it is a certainty. Further problems will occur due to unrealistic expectations by all the parties involved in a dispute.

Measurement disputes over gage calibration continue despite the results of the studies noted in my previous column.

The American Measuring Tool Manufacturers Association (AMTMA) is an organization whose members manufacture, supply, and/or calibrate precision gages and measuring instruments. If you use this type of equipment, the odds are it came from one or more AMTMA member companies.

Readers of this column will be familiar with the subject of measurement uncertainty since I comment on it from time to time, as I did last month. Those readers that have not been that interested in it will certainly run across it on reports from their calibration sources.

The American Society of Mechanical Engineers (ASME) has published a new standard that identifies elements that will impact measurement uncertainty from thread calibration processes. 

Readers of this column are a gentle lot and not likely to run afoul of criminal law but can end up in a similarly frustrating situation that limits their working life.

This is an area of gage making that takes something simple like a go/nogo plain plug gage and adds another feature for another check, such as hole depth.

This question would seem to be an easy one to answer but—like too many things in life—nothing is simple anymore. This is due to the absence of standardized rules on which to base the decision which will vary from one organization to another.