Irregular Features as Datum Features

In this question line video, Jason answers the following question regarding the use of irregular features as datum features:

Can Datum A be applied to a hex shape? My colleague has identified a hex as Datum A, but three center planes may not intersect exactly at a line.

In the above drawing, a hexagon shape is identified as Datum Feature A and is used as the primary datum feature in the feature control frame. In this video, Jason explains how an irregular feature like a hexagon can serve as a primary datum feature. Jason discusses how the true geometric counterpart is utilized to establish this control and he also covers how the other features are located and oriented to this datum. He the briefly explains how this part could be inspected – touching on gage design for manual inspection and point cloud analysis using a CMM. 

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