Positional tolerance with RFS
Hi Friends,
Iam working on a drawing with a positional tolerance of hole is given as Dia. .579-.578 , with 0.02 as the valve in feature control frame to datum reference A and B, please help me to find the dimension at RFS to consider for inspection.
Last edited by Srinivasrouthu; 01-09-2015 at 05:36 AM. Reason: spelling mistakes
The feature control frame (position tolerance) is not associated with the hole feature to any know standard. The leader arrow should be clearly associated with the feature to be tolerance controlled and not the feature control frame. Therefore, it is not clear though I assume that the position tolerance is meant to be associated with the only hole feature shown.Originally Posted by Srinivasrouthu
There should be a basic dimension or Theoretical Exact Dimension TED associated and clearly defining the location of the hole feature relative to the datum's A and B. Also, the Datum's are not shown correctly on the engineering drawing within the illustration that you attached to this forum therefore the location of the datum's are not known.
In other words - there is no way to tell what the basic or TED dimension is locating the hole to the datums.. If I were forced to guess - I would assume that the hole was meant to be symmetric about the height however there is no way to know the depth relative to the view.
You need to ask the engineering drawing creator to clarify the basic or TED distance dimensions, the referenced datum's and clean up the syntax on the drawing as well.
Good luck...
Links to GD&T books and training
Geometric Boundaries II Interpretation and Application to GD&T
GD&T Training ASME Y14.5-2009, Geometric Dimensioning and Tolerancing
Last edited by Kelly_Bramble; 01-09-2015 at 08:44 AM.
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