Abstract: A pilger die assembly in which the die has an annular body with an opening extending from a central, through bore to the peripheral surface. The opening subtends a circumferential angle at the through bore of less than 180.degree.. The cylindrical arbor has a section of reduced cross-sectional dimension, preferably formed by a flat. The die is positioned with the opening aligned with the flat, slid into coaxial registration with the arbor, rotated to a captured position in which the opening is no longer aligned with flat on the arbor and then pushed axially to engage a key on the arbor in a keyway extending axially from one side face of the die. A stop screw threaded into the arbor adjacent the other side face of the die locks it in place.

Abstract: Disclosed is a groove measuring gauge. The gauge has a centering headpiece and centering tailpiece for supporting a die or other workpiece mounted upon an arbor. Two guideways are used to position a gauge head near the workpiece containing the groove being measured. The gauge head has a spindle rotatably mounted therein. The spindle includes a measuring arm which extends from an interior cavity in the spindle. The measuring arm is pivotably mounted in the spindle. The exposed end of the measuring arm contacts the inside surfaces of the groove. A micrometer is mounted upon the spindle and connected to the enclosed end of the measuring arm. As the measuring arm pivots the micrometer measures the distance from the spindle axis to the surface of the groove. The spindle is preferably automatically moved to angular positions by a stepping motor. Micrometer readings are taken at each position and the profile of the groove is determined from these measurements.