I have searched in the Y14.5-2009 standard and online and have not been able to find an answer to this question. Is there a way to reference a step file as basic geometry to apply a profile of a surface tolerance?
The main purpose is to define a tolerance zone for surfaces with compound curves and other shapes which are not straightforward to dimension. I would expect that these parts would be inspected with a cmm, but could also be inspected (very tediously) using manual means. I would use datums to orient the step file geometry.
All of my searches point me to adding GD&T callouts to step files, which is not what I'm trying to do.
Is there an accepted means for referencing step files through gd&t?
Yes, this is a common practice of having a note that "geometry and dimensional data shall be derived from the electronic database". Some organizations have a title block area defining the reference CAD or other file (CAD, xls, stp, iges, etc.) from which manufacturing other others will use.
These types of engineering drawings area often called "Limited Dimension Drawings" or Critical Feature Drawings.
For more information see: https://www.engineersedge.com/ldd-cfd.htm
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