Abstract: A component measuring machine includes a base on which a carriage is mounted for movement along an x-axis. A compound slide structure is mounted on the carriage for moving a cradle along y- and z-axes. A support on the carriage and the cradle supports an arm so that it is angularly movable about a point relative to the carriage. Thickness measurements can be made by means of a caliper structure mounted on the end of the arm, which can be turned about its own longitudinal axis for varying the orientation of the caliper structure. The precise positions of the contact tips of the caliper structure are determined by accurately monitoring displacements of the carriage and the compound slide structure, and turning of the arm on its axis.