The Y14.5 Standard gives us two ways to tolerance slots. The one specifically shown for slots is on the first drawing. It requires two position tolerances (both labeled BOUNDARY) and leaves the allowable variation of the rounded ends a little fuzzy. The second method shown on the second drawing is a little cleaner and actually does a better job …
Tolerance Those Slots Right (#214)
(In accordance with Y14.5M-1994 standard)
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