a fixture and technique for testing a coil spring selected from a supply of springs . each spring has an unstressed generally helical configuration and the test determines an excess departure from the helical configuration of a spring under a compressive load . the first end of a selected spring is radially fixed in a first guide while a second end of the spring end is axially retained in a movable second guide that is supported on rollers to allow omni - directional transverse radial motion of the second end . an axial compressive force is applied to the selected spring while allowing the second end relatively free radial motion . when compression induced radial motion of the second end exceeds a predetermined threshold , the second end the selected spring closes a normally opened electrical circuit to inform an operator that the selected spring is excessively out of square and should be rejected .