Can’t believe most inspectors and especially engineers don’t know this!
On a hole diameter MMC = Actual measured hole size minus the smallest allowable size which is the MMC condition… max material.
So for TP .5 on a 10.0 +/- .5 hole that measures 10.1
You get .6 Bonus (actual size 10.1 minus the smallest size 9.5 = .6) this .6 extra tolerance is then added to the given .5 TP tolerance for a grand total of 1.1 tolerance.
For a solid pin or outside cylinder it’s outside diameter, same concept. Largest allowable size minus the actual = Bonus Tolerance.
BONUS TOLERANCE =
DIFFERENCE BETWEEN MMC SIZE AND ACTUAL SIZE! ADDED TO GIVEN TP TOLERANCE IN THE FEATURE CONTROL FRAME.
