Abstract: A coordinate measuring machine has a horizontal rail defining an X-axis, a vertical rail movable along the horizontal rail defining a Z-axis, and a horizontal arm orthogonally situated relative to said X and Z axis defining a Y axis. Pairs of opposed track surfaces integral with the rails are engaged by pairs of wheels for rolling movement of the axes relative to each other. Biasing means such as coil springs urge the wheels of each of the pairs into contact with the opposed track surfaces in order to accurately maintain desired orthogonal relationships between the axes.

Abstract: A coordinate measuring machine having three elongated members defining X, Y and Z axes is provided wherein the Y axis is defined by a horizontal arm extendedly and retractably mounted in a housing supported on the rail defining the Z axis. The horizontal arm is provided with convex ridges on its upper and lower surfaces. The ridges preferably extend along the center line of the arm. The arm is supported by upper and lower pairs of wheels having concave surfaces located in the housing.

Abstract: A frame straightening and measuring system for auto body repair is provided including position locating arms moveable along each of three axis, each of said arms being provided with an extendable retractable measuring device such as a roll-up type tape measure provided with means for clamping the free end thereof at a desired location on the extendable position locating bars whereby the correct position of a damaged part relative to the axis of the motor vehicle can be determined accurately.