Spotty Cadmium Plate
Q. What causes cadmium plating to look spotted and uneven? We are using a cyanide-based cadmium plating solution. –E.M.
A. Spotting out of a cadmium deposit is usually caused by one of the following:
1. Rinsing after completion of the plating step is not adequate. The parts should be dipped a number of times alternating in cold and warm water rinse baths, and ending with a warm rinse.
2. You may have a porous cyanide deposit that usually is due to inadequate cyanide in the plating solution. Check the cyanide concentration and adjust accordingly.