The ball diameter automatic measurement device according to the present invention preferably comprises a displacement sensor, a dividing plate, a slider and a measurement controller. The displacement sensor measures the diameter of a ball positioned in a measurement position. The dividing plate holds a ball to be measured and reciprocates the same between a predetermined position and the measurement position. The slider rotates the ball in the predetermined position by a predetermined angle when the dividing plate is moved. The measurement controller stores and outputs measured values obtained by repeated measurement and measurement after the rotation of the predetermined angle. According to the device, it is possible to measure a ball diameter accurately without being influenced by body temperature, air temperature and individual workmanship when the diameter of a ball is measured.

A solid core fixture for measuring a workpiece and a method for making the same. The solid core fixture includes a solid core made of a homogeneous material, a skin layer covering the solid core, and a surface material covering a portion of the skin layer. The surface material is machined for measuring the workpiece. The skin layer preferably includes an inner skin covering the solid core, a skin core attached to the inner skin and an outer skin attached to the outer surface of the skin core, the three layers being molded in a single process and cured together. A method of making the solid core fixture includes the steps of fabricating a plug core from a homogeneous material; attaching the plug core to a base; applying a skin layer to the plug core and the base; curing the skin layer; covering a portion of the skin layer, after curing, with a surface material; and machining the surface material for measuring the workpiece. Preferably, the applying a skin layer step comprises the steps of: applying an inner skin layer over the plug core; applying a skin core over the inner skin layer; and applying an outer skin layer over the skin core; then the curing step is performed on all layers of the skin layer during a single curing time.

An apparatus and method for determining compliance of a lacrosse stick head with dimensional specifications that require a minimum allowable width between the two sidewalls of the head as measured at a designated distance from the stop member of the head. The apparatus has a width equal to the minimum allowable width of the lacrosse stick head, and a length perpendicular to the width. The length is equal to the designated distance. The apparatus is adapted to simultaneously measure the designated distance and the minimum allowable width. In a specific implementation, the apparatus has an upper rectangular portion connected to a lower triangular portion.