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Pattern - Simultaneous Requirements
   If You Don't Want a Pattern, You Have to Say So!

Because of the simultaneous requirements rule stated in section 4.5.12 in the Y14.5 Standard, if features are controlled relative to the same datum reference frame, the features are considered to be a pattern. Both drawings shown below indicate that the two keyseats are a pattern and must be located as shown. 

The keyseats are considered to be a pattern. Their orientation is controlled by the position callout(s) 



In order to unlock the orientation of the two keyseats to one another, a note indicating separate requirements must be stated.

In this example, the orientation of the keyseats is unimportant.

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