Abstract: An apparatus and method are disclosed for electrochemically finishing or smoothing an irregular anode surface of a conductive metal part while removing a minimum of metal from the anode surface. The smoothing or finishing of irregular surfaces, such as burred surfaces, for example, is achieved by mounting the face of a cathode member adjacent the anode surface to be finished to define a minimum gap therebetween and moving the face relative to the anode surface while subjecting the face and anode surface to a flow of electrolyte fluid through the gap. An electrical power means is coupled to the face and anode surface for generating a current therebetween through the electrolyte for electrochemically finishing the burred anode surface with a minimum removal of metal therefrom.

Abstract: A method and apparatus for electrochemical rifling of gun barrels and the like is disclosed. In one embodiment of the apparatus, an elongate pressure chamber for receiving electrolyte fluid under pressure is mounted in alignment with an anode gun barrel and in fluid communication therewith. A cathode rod rifling assembly is mounted in the pressure chamber in axial alignment with the gun barrel. Drive means simultaneously rotates the rifling assembly and moves it relative to the barrel for passage of the rifling assembly through the barrel along with the electrolyte fluid. In another embodiment, the rifling asembly comprises first and second adjacent segments joined on a plane. Each segment has peripheral, radially outwardly extending, circumferentially spaced strips of insulation which are out of alignment with, and overlap, one another along the plane. The overlapped regions define the width of the unetched portions or lands on the barrel.