Abstract: A chemical machining method and apparatus for forming an internal tpaer in the walls of a sleeve-like body, such as a copper liner of a continuous-casting mold. The body is partially filled with an etching solution, whereby the inside faces of the body are exposed to a pool of the solution. The pool is agitated by blowing air therethrough. By proper control of the rate at which the level of the pool rises or falls within the body, any form of linear or curvilinear taper can be obtained.

Abstract: A process and apparatus for the high current density electroplating of recessed configurations such as inside corners or depressions. The apparatus employs a housing member, the front face of which has a number of closely spaced ports for the discharge of electrolyte jets which impinge upon the recessed configuration. The anode, supported within the housing, is non-consumable so as to prevent soluble anode products from depositing within the recessed configuration. Uniform plating is achieved by a new principle termed "coalescent jets" which requires a critical correlation between (i) the applied voltage, (ii) the force of the electrolyte jets, (iii) the size of the ports, (iv) the distance between ports and (v) the distance between the front face of the housing and the recessed configuration undergoing electroplating.