Abstract: To enable the on-machine measurement of selected features of a workpiece formed on a live spindle lathe with a positioning rotary table, both the machine itself and the electronic touch probe used to conduct the measurements are calibrated. The accuracy of the machine itself is measured and calculated by including the measured errors not only in the x and z linear axes, but also in the y linear axis. Calibration of the touch probe is made by determining a correction factor which is obtained by the touch probe measurement of an artifact whose dimensions are precisely known by other means. This correction factor is then made to the nominal measurements made by the touch probe on the selected features of the workpiece to be measured, to obtain the actual dimensions thereof. Adjustments are also made to compensate for the differences in radial positions between the workpiece and the artifact.

Abstract: A coupling connects a first member and a second member. The first member has a first interlocking member extending radially outward from an outer circumferential surface of an axial end. The second member includes a second interlocking member extending radially inward from an inner circumferential surface of an axial end. The axial end of the first member is inserted into the axial end of the second member, such that the first interlocking member is inserted past the second interlocking member. The first and second members are then rotated relative to one another to a locked angular orientation, in which the first interlocking member is interlocked with the second interlocking member to prevent relative axial movement of the first and second members. A key is then inserted into a keyway in the first and second members to lock the angular orientation, thereby coupling the first and second members to one another.