The Importance of Qualifying Datums

In this Question Line video, Jason answers the following question regarding the importance of qualifying datums:

What is the normal approach to inspecting and interpreting this drawing?

 

The drawing in question is shown below:

 

In this video, Jason discusses the difference between how CMMs and physical datum simulators set up the datum reference frame for a manufactured part. Through this drawing example, he shows why physical datum simulators are best at establishing the correct zero point (0,0,0) of the datum reference frame. He also explains how the datums for this part would be qualified and that the combination of datum simulation and datum qualification will solve the ambiguity coming across in this drawing.

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For more information on datum qualification, see:

Relating Secondary Datum Features to Primary Datums

Part Setup and Datum Qualification Using a CMM

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