an improved in - track welder eliminates conduction path force members and employs separate bridging current path conductors for dc welding of rail ends . in an embodiment , this enhancement allows for an increased closure distance , thus improving cold - weather operations . in a further embodiment , an increased allowable distance between conduction contacts also allows for the incorporation of an internal shear member for more efficient finishing of welds . the force members may be optimized for strength rather than electrical properties , and in an embodiment are comprised of relatively small diameter alloy steel rods .