Abstract: Apparatus for winding a linear, elongated object into a coil including a bending roller assembly for bending the linear, elongated object into loops of the coil, and a leveling device for bringing the curvature of the coil to a predetermined level. The leveling device includes a base movable toward and away from the bending roller assembly so as to adjust the spacing between the bending roller assembly and the base, a plurality of sliders supported by the base and located circumferentially of the coil in spaced relation to one another for movement in sliding motion toward and away from the center of curvature of the coil, a plurality of leveling roller assemblies each supported by one of the sliders for imparting a bending moment to the coil to correct the curvature thereof to a desired value, and an actuator for radially positioning the sliders in accordance with the spacing between the bending roller assembly and the base.