A DC arc furnace comprising a furnace vessel having a hearth and a side wall extending upwardly from the hearth, conductive means for conducting DC through the hearth from its outside to a melt in the hearth, an arcing electrode, a substantially horizontal arm having a holder holding the electrode substantially vertically above the hearth, a substantially vertical mast from which the arm extends, and means for connecting DC positively to the conductive means and negatively to the electrode so as to form an arc between the electrode and the melt and producing an arc flare to which the side wall is exposed; wherein the improvement comprises means for connecting the arm to the mast so as to permit the arm to be adjustably moved longitudinally to different positions and means for mounting the mast so it can be adjustably rotated to different positions about its axis, whereby the electrode and its arc can be located at different positions horizontally to the side wall.