 Angularity Does Not Locate -
Use Position Tolerance
Here is another case where angularity cannot
fully define the feature. The original drawing had angularity
rather than position applied to the 10mm wide slot. The
drawing shows that the center of the slot should be in line
with datum axis B. Angularity would assure that the slot is at
the 60° basic angle but ignore that the slot center plane
should pass through the datum axis. To keep the slot in line
with the datum axis, position needs to be applied to the slots
size dimension. If the angle of the slot needs to be
controlled better than the angularity provided by the position
tolerance, an angularity tolerance may be added as a
refinement. As we teach in our GD&T seminars, for
features of size, locate first with position and refine with
orientation, in this case angularity, only if necessary.
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