Abstract: A method of measuring the bends in a preformed tube by locating in space, with a mechanical tube-engaging apparatus, the centerline of each straight tube section. Where the bends are measured of a tube which is longer than the physical boundaries of the apparatus, adjacent portions of the tube are successively positioned within the boundaries of the apparatus and the centerlines of sufficient straight tube sections are located with the tube in successive positions to correlate the tube position and orientation at the successive tube positions. In measuring a tube with a straight section of such a length that bends at either end thereof cannot be correlated at successive tube positions within the physical boundaries of said apparatus, an apparatus is attached to the straight section of the tube to create simulated bends within the long straight section, enabling measurement of the bends at each end of the long straight section.