Dealing with a Datum Feature that Is a Rocker (#226)
(In accordance with Y14.5M-1994 standard)
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I am often asked how to set up a part when a datum feature is unstable. On this drawing datum feature A has a flatness tolerance of 0.2. If the feature is produced with a concave surface, the part will contact the simulated datum on the high points and establish a datum plane. However, if the surface is convex or bowed it will “rock” …
