Standard Geometric Characteristics and Symbols

The Geometric Characteristics, Symbols and Parameters that are used as the building blocks for geometric dimensioning and tolerancing, and M.O.I. standard tolerances for them are listed in the table below:


SYMBOL CHARACTERISTIC TOLERANCE
FLATNESS 10λ/INCH
STRAIGHTNESS .005″ (.13mm)
CIRCULARITY (ROUNDNESS) .010″ (.25mm)
CYLINDRICITY .010″ (.25mm)
PERPENDICULARITY (SQUARENESS)
ANGULARITY
PARALLELISM .005″ (.13mm)
PROFILE OF A SURFACE .030″ (.75mm)
PROFILE OF A LINE .020″ (.5mm)
CIRCULAR RUNOUT .010″ (.25mm)
TOTAL RUNOUT .010″ (.25mm)
POSITION .020″ (.5mm)
CONCENTRICITY .010″ (.25mm)
SYMMETRY .010″ (.25mm)

NOTE: THESE TOLERANCES APPLY TO MACHINED PARTS ONLY – NOT TO FIRE-POLISHED PARTS