Reverse Inspections of Orientation
In this Question Line video, Jason answers the following question regarding reverse inspections of orientation:
I am trying to check the parallelism of the surface of a part in relation to Datum A. Is it acceptable to locate off of the surface of the part and indicate on the Datum A?
Jason walks through the example shown below to explain why you should not deviate from the inspection criteria given in the feature control frame, noting that inspection will give a value that represents the combined effects of form as well as orientation. Reversing the inspection by placing the toleranced surface on the granite table and indicating off of the datum feature would give false results.
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