August 22, 2008

Thicker Nickel Plating

Against these considerations the commercial electroplater has to balance the fact that this plant is occupied longer for the nickel deposits and the costs rise proportionately. The adequate of thickness of the nickel electroplates does not become apparent until long after it is delivered. For these reasons a British Standard Specification and numerous other private and foreign specifications lay down the minimum permissible thickness of nickel plating on any part of an article for various types of service, and describe and specify means of checking this. To achieve safely the minimum thickness specified for steel motor car parts exposed to the weather (0.0012 in) may involve depositing at least 0.002 in average thickness, i.e. h plating at 20 A/ft2 or 40 m at 60 A/ft2. Thinner nickel plating for use under milder conditions of exposure or other basis metals is also covered in these specifications.

It should be made clear that many articles may be nickel plated at the same time in one nickel plating tank, provided that they do not shield one another from the flow of current from the anodes. The entire article may be put in and withdrawn together, or they may be put in and withdrawn in sequence, provided only that each one gets its proper share of the current and the requisite time.

After the selected period of electroplating the racks or wires carrying the articles are lifted out of the plating tank, thoroughly rinsed in running water to avoid stains and then dried, usually in a current of warm air. The parts may be then detached from the racks or wires. Inevitably, valuable nickel plating solution adheres to the parts or is trapper in recesses, etc. This is called 'drag-out' and is lost during rinsing. Except for this loss the nickel plating solution is little changed in the plating process since the nickel metal plated out from it is automatically replenished from the anodes.

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