Gear Specifications on Engineering Drawings
The geometrical data for spline gear teeth are too extensive to specified directly on the engineering drawing as dimensions. It is therefore recommended that these be indicated in the form of a data field.
If the method of measurement has to be specified, it is also possible to state a measuring ball or measuring pin diameter instead of the measuring circle diameter. The dimension over or between measuring circles is then stated either as the dimension over or between balls or pins, accordingly.