Abstract: A system for electroplating a tin-bismuth alloy at near eutectic composition is disclosed. The system includes the plating bath and the process for initially preparing the bath as well as the process for plating an object with tin-bismuth alloy. The system further includes an apparatus for regulating the concentrations of tin and bismuth in the plating bath and the process by which the concentrations are controlled.

Abstract: A system for electroplating a tin-bismuth alloy at near eutectic composition is disclosed. The system includes the plating bath and the process for initially preparing the bath as well as the process for plating an object with tin-bismuth alloy. The system further includes an apparatus for regulating the concentrations of tin and bismuth in the plating bath and the process by which the concentrations are controlled.

Abstract: An electroplating rack is constructed of corrosion resistant stainless steel, with oppposed side frames milled with vertical channels to accommodate opposite side edge portions of a printed circuit board for plating. Mechanical and electrical connections with the circuit board are made with recessed stainless steel screws with rounded tips. Current is provided to the top of the rack, and also to the bottom of each side frame through an elongate, vertically disposed copper bar surrounded by an insulative sheath and contained within each side frame. Each of the copper rods is threadedly engaged in a steel end cap at the bottom of the associated frame. The current fed into the top and bottom of the rack can be adjusted by adjusting the comparative conductivity of the two paths.

Abstract: In a system for electroplating a printed circuit board in which multiple spray orifices are provided in arrays on opposite sides of the circuit board, and multiple vacuum orifices are interspersed symmetrically and midway between adjacent spray orifices, a mounting means is provided for rapid and accurate locating of the printed circuit board in two selectively offset alternative positions to facilitate forming an electroplated layer of uniform thickness. The printed circuit board is supported from an elongate copper bar, with two alignment members mounted to opposite ends of the bar. A pair of saddles are fixed with respect to the tank containing the electrolyte. Each of the saddles has two V-shaped mounting surfaces conforming to the alignment members for a nesting engagement.