Here’s the job I was working on a long time ago – a massive granite beam held in place with M20 tie-rods in an anchor plate. The clearance holes in the beam were Ø30mm, so lots of room.


So I did the drawing using classical tolerancing, which should have been fine. A ±0.01mm tolerance should be more than needed to clear in case the holes weren’t perfectly straight.

This is how the tie-rods looked in the manufactured plate – not straight and there’s no way this will fit in the granite beam. The shop apologized and remade the plates with straighter tapped holes and it worked. They only had to remake 2 plates. Of couse the schedule took a hit.
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