Brush Electrofinishing without the Mess

Anyone who has recently made the acquaintance of their local OSHA inspectors checking their compliance with the Cd and hex Cr housekeeping regulations knows that plating or stripping toxic materials can be very bad for their financial health.  Any process that risks exposing employees to Cd or CrVI, especially tracking it out of regulated areas into the general workplace, is no longer acceptable.  Surprisingly, a new tool that is available to help combat this problem is brush plating (or more correctly electrofinishing).

Brush electrofinishing has always been considered the poor relation of “real” electroplating.  It is seen as something messy and ill-defined, dripping toxic chemicals with little or no quality control.  New technology is now available that overcomes both of these problems, while incorporating other electrochemical processes such as electrochemical stripping and anodizing.

In non-drip brush electrofinishing, electrolyte is pumped through the electroplating pad (stylus) and back into a holding tank in a closed loop that prevents dripping.  This makes it possible to brush electroplate or anodize in difficult locations such as overhead on an aircraft, as well as making it possible to strip toxic materials such as cadmium without exposing the operator to the stripped product, or leaking solutions into areas from which they can be tracked elsewhere in the plant.

In order to eliminate the vagaries of a process that is done by hand, the equipment is computer-controlled to ensure that all the proper steps are followed and the correct process conditions are maintained, as well as providing a voltage/current record of the process for Quality Control.

This paper will describe the equipment and its use in a number of plating, anodizing, stripping, and other electrochemical processes used by aircraft operators around the world.