This invention relates to a roller for a wire-feed device having a main cylindrical body forming a hub designed to be driven in rotation about its axis of symmetry, a peripheral cylindrical structure forming an idler roller mounted round the perimeter of the main body, and a means for the cylindrical structure to be driven in rotation by the main body. Moreover, the internal diameter of the cylindrical structure is greater than the external diameter of the main body so as to create a space between the cylindrical structure and the main body to enable a displacement of the cylindrical structure in relation to the main body with a misalignment of the axis of rotation of the cylindrical structure in relation to the axis of rotation of the main body.