Setting Position Tolerances

[inguesu]

So I've been searching for material to help me set tolerances for mating surfaces. Everything I have found only applies to one bolt, kind of like the attached file. My question is does anyone have any recommendations on how they go about setting tolerances for a pattern of holes and bolts, so that at as a dimension leaves or approaches (M) it will all still mate.

http://files.engineering.com/getfil...27c62c8&file=APPENDIX_B4_ASME_Y14.5M-1994.xls

 

[3DDave]

The tolerances apply based on the parts being aligned to each other by their respective datum reference frames. Since the holes in the pattern share a datum reference frame they will all go together as a group. Whatever applies to one hole will apply to all of them.

 

[mkcski]

Of note: The examples usually divide the total available position tolerance (difference in MMC sizes) equally (by 2) between the faster and hole. This is NOT a requirement. You can assign any values to each as long as the total equal what is available.

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