The chrome plating found on car trim and kitchen appliances can also be made at home. Using electrolysis, it’s possible to bind chromium onto metals such as steel, brass, copper, aluminum and stainless steel, creating the shiny finish. In addition to creating a polished layer, the element also stops the metals from tarnishing. Remember, though, the process requires very strong chemicals, so caution should be taken before starting the process. Be sure to wear safety goggles and gloves as well as a dust mask.
Things You'll Need:
Alkaline cleaner or chrome stripper
- Sulfuric acid
- Distilled water
Dry acid pickle
- A tank large enough to fit the object to be chromed
Thermostatic tank heater
Variable current controller (makes it possible to use a car battery or charger for plating)
Thoroughly clean the material to be chromed. This includes degreasing (with a solution such as alkaline cleaner) and removing any paint, rust and dirt. Don’t forget that the grease from your hands can cause problems, so wear gloves during the cleaning process. The more thoroughly prepared the surface, the better the finished coating. A grinder or buffer may be helpful for the process. If there are any nicks or dents, smooth them out.
Douse the metal in a dry acid pickle, which is necessary to prepare the metal for plating and also keep an oxide layer from forming. The pickling time will vary depending on the metal being plated. Be sure to follow the pickle manufacturer's instructions.
To make a chromium plating solution, you’ll need a combination of chromic acid, sulfuric acid and distilled water. Combine the chromic acid with sulfuric acid fluid in a 100 to 1 ratio. Then, add this solution to the distilled water. The amount of each of these ingredients varies according to the size of the piece you’ll be plating and the type of surface material. These ingredients are also available in chrome plating kits, which may also include the necessary tools. The chemicals in the chromium plating solution are carcinogenic as well as flammable, so they should be handled carefully.
The immersion tank for the process should have enough room to fit any surface to be plated. For decorative chrome, the solution should be heated between 95 and 115 degrees Fahrenheit. For hard chrome, the solution needs to be a little hotter, between 120 and 150 degrees Fahrenheit.
Dissolve the plating material in the solution.
Run a positive charge from the variable current controller through the plating solution.
Attach a negative anode to the metal piece to be chromed. As a result, positively charged pieces of chromium will be attracted to it. The longer the metal is submerged in the tank, the thicker the resulting chrome plating will be.
After the chrome plating is complete, remove the object from the tank and rinse at least twice in running water.
- Warning: While the gasses from chroming don’t have a distinct odor, they can be very toxic when inhaled. Be mindful to wear protective gear, including goggles, a dusk mask and gloves, and read the manufacturer’s instructions.
Neil Gladstone's writing has appeared in The New York Times, USA Today and Popular Mechanics. He's also the co-founder of the DIY community CraftFoxes and The Craftys, awards for makers and crafters.