Geometric Tolerance for a Hole expressed with a M modifier
Where M or L modifiers are assigned to a Geometric Tolerance, the variation is caused by the following tolerances:
- The Tolerance of Size
- The Geometric Tolerance
- Bonus Tolerance that accrues when the Feature size goes away from the Critical Limit of Size.
Bonus Tolerance is a useful concept that makes manufacturing processes less expensive. DVA needs to take correct cognizance of the 3 tolerances above to evaluate the Feature envelopes and consequently the gap. The animation shows a case of gap variation, when the Geometric tolerance is expressed with a M modifier.