The primary function of barrel plating is to enable parts to be plated economically, with low labor cost. Small to medium sized parts that can withstand tumbling without distortion due to part on part contact are good choices to barrel plate. Depending on the size of the order and geometry of the part various barrel sizes are employed to achieve optimal results. The rotation of the barrel while in solution is also very important and can be sped up or slowed down depending on the type of part being processed. Barrel plating is considered the most economical way to plate parts.
Rack plating is used to finish larger, fragile, higher reliability components that cannot be coated using other batch plating methods. It’s best suited for smaller quantities or if no damage at all is allowed to the part. Parts are wired or hard fixtured on plating racks and then submersed in the plating solution with current applied. It’s a more labor intensive method of processing since each part is being individually handled so cost is obviously much greater than barrel plating.
Vibratory plating is another method of batch or bulk processing that employs vibration rather than cylindrical barrel tumbling to plate. Parts loaded into a vibratory head and once turned on, the motion generated provides smooth sliding of the parts and the work load is in continuous motion. The movement of the parts can be adjusted by changing amplitude and frequency of pulse depending on the type of part being run.