Use Two Datum References for Angularity - 1994, 2009, 2018 (#32)
(In accordance with the ASME Y14.5-2018 standard)
(In accordance with the ASME Y14.5-2009 standard)
(In accordance with Y14.5M-1994 standard)
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When setting up a part for the measurement of angularity on a sine bar, it is difficult to orient the part before performing the inspection. The part is free to rotate on the inspection surface, so even if it fails inspection once, it may pass when reoriented, making inspection time consuming.
This problem is overcome if a second datum is referenced in the angularity callout. In this case, rotation about the primary datum is constrained, so the part is always set up on the inspection equipment the same way and the inspection result is repeatable.
This tip is in accordance with ASME Y14.5M-1994, Y14.5-2009 and Y14.5-2018.
This tip was originally released in February 2000.
