Position vs Runout

In this Question Line video, Jason answers the following question regarding position vs runout controls for turned parts:

How critical/applicable are true position on turned/lathe parts if they were turned and drilled at the same time while in a constraint state when from what I understand it is more related to milling.

The above drawing submitted with the question shows the inside diameter of this part being controlled with a position tolerance relative to Datum A. Datum A is an axis established from Datum Feature A, the outside diameter of the part. This control ensures that the axis of the inside diameter is closely related to the axis of the outside diameter – keeping the two features coaxial.  

Jason explains that this method is valid, but that it’s more common to see circular runout or total runout used to control this relationship on turned parts. In the video, he walks through how Datum Axis A is simulated and how the deviation from that axis is collected for both the position control and the runout control, highlighting the differences in how each is evaluated and what each control is actually limiting. 

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