Restoring Zinc And Pot Metal Castings
Q: How do you restore old zinc or pot metal castings used on classic automobiles? I own a number of antique automobiles that are in various stages of restoration. I want to restore the chromium components but I do not have the budget to have this work done by local electroplaters. Any help that you can give me would be appreciated. C. K.
A: The restoration of old automobile parts that are severely pitted is a rather specialized area of expertise. One method that has been used to repair castings consists of thoroughly cleaning the plated parts and then “scooping out” the pitted and corroded areas. The parts are then given a cyanide or a non-alkaline cyanide strike followed by a thin copper plate. The next step involves filling the areas of the pits with solder. After filing, grinding and buffing of the soldered areas, a layer of copper is applied to the part. The thickness of the copper layer should be at least 0.001 inch. After the parts are buffed to a high luster, they are nickel and chromium plated.
As you can see, this process is time-consuming and labor-intensive. That is why your local electroplater has to charge you a significant amount of money to do the work. In addition, the local electroplater has to handle materials that are environmentally nasty.
Your question implies that you are thinking of doing this work yourself. I would only consider this if you are willing to obtain the training and equipment necessary for doing the job properly.