It’s All a Matter of Plating
When you design your own coin, choosing the metal plating is one of the most important steps. The variations of gold and silver are by far the most popular, and there are also beautiful copper and nickel options to choose from. While each of these metal finishes look different, they all share one thing in common: They’re added to a coin via the electroplating method.
Electroplating isn’t the only way to achieve a unique finish for your coins. The other option is powder coating. If you’re looking for a black metal coin or perhaps a red, pink, green or orange metal coin, powder coating is the only way to go. Whether you choose the electroplating route or the powder coating route, you’re sure to end up with a beautiful coin design that meets the industry’s highest quality standards.
The only time we experience some speed bumps in the production process of these types of coins is when a customer is looking for a design that combines them. Dual plating is a sure way to make your design stand out from the crowd, but there are a few things that can go wrong when trying to combine powder coating and electroplating on the same coin. With this in mind, we thought it would be helpful to talk about the differences between the two plating methods and show off a few examples of coins that combine powder coating and electroplating.
The Beautiful Pairing of Black and Gold Metal
Let’s start with the differences between powder coating and electroplating. No matter what style of colored metal or precious metal you choose, all challenge coins start in the same place. Once we complete your custom artwork, the challenge coin production process gets underway. Our production team machines a custom mold and proceeds to stamp out your coins onto sheets of zinc, brass, steel or iron, and in some rarer cases, copper.
This is where a black metal coin and a gold coin will part ways on the production line. If you chose a powder coated black metal coin, all of the newly struck challenge coins will move to the powder coating room. If you chose an electroplated gold coin, your fresh challenge coins will move to the electroplating room.
This separation at the very beginning of production is where issues start to arise when creating a dual plated coin with powder coating elements and electroplating elements, like this design created for the TrainOurTroops organization.
To create a black metal finish, our production team uses a free-flowing, dry powder that’s typically made from thermoplastic or a thermoset polymer. In the powder coating room, the colored powder is applied to the coins electrostatically, meaning that it’s sprayed onto the coins using a special gun that shoots the powder through a positively charged electrical current. The coins, grounded with copper wire, are given a negative charge, which causes the colored powder to attach to the metal.
Once the coins are completely covered, they are baked in an oven to let the powder cure. As the powder melts, it forms a permanent layer of color over the entire surface of your coins. When we leave the powder coating room and check out the electroplating process, things look a little different.
To add gold metal plating to a freshly struck coin, it needs to be added to a liquid solution containing 24k gold. Similar to the electrostatic charge used to adhere powder to a coin’s surface in the powder coating room, an electrical charge is sent through the liquid solution containing the coin and the gold. The chemical reaction that takes place ensures that a thin, permanent layer of precious metal is sealed over the entire surface of the coin.
It’s obvious to see that we can combine both powder coating and electroplating in the same design by looking at the TrainOurTroops coin above, but there are a few big steps that need to be added to the production process to make it work. The best way to explain how it works is with an example.
Potential Problems When Mixing Powder Coating and Electroplating
This coin is a beautiful example of black metal and precious metal working together in the same design. However, instead of having just black and gold like the previous coin, this coin is triple plated with black, gold and silver, resulting in a truly remarkable design.
To achieve this effect, the coins need to go through electroplating. The coins are first plated in gold and then put through electroplating a second time to add the silver metal to the design. A special paint is added to the sections of the coin which are not getting the second metal plating. This dual plating process takes time and patience to get right, and it must be done before powder coating can take place.
After the dual plating, the gold and silver USN Petty Officer rank insignias needed to be covered up to preserve the metal finish. This process is similar to how a painter uses painter’s tape to prevent colors from bleeding over onto a piece of crown molding or a wall of a different color.
The issues that come up at this point are twofold. Once the newly powder coated coins are removed from the oven and the protective layer is removed from the gold and silver portions of the design, it’s possible to discover that some of the powder was able to get through and bond with the precious metal surface. This creates a blotchy finish for the precious metal, which is supposed to be clean and crisp.
The second issue also has to do with removing the protective layer over the precious metal. As the coins cool off, the black powder hardens. If the protective layer covering the gold and silver metal is taken off after the black metal has cooled, it can cause the black finish to chip or crack.
What to Expect When Combining Powder Coating and Electroplating in Your Own Design
Combining different variations of gold, silver, copper or nickel with electroplating is a straight forward process, but it will add time to production. When you achieve a multi plating effect with powder coating and electroplating, it’s going to take even longer. So, if you’re looking for something like these black metal coins with added gold and silver metal in the design, you should expect the production to take a little longer than average.
Since the two styles of plating are so different, creating coins that combine powder coating and electroplating comes with the added risk of defective products. This doesn’t mean the coins you receive will have problems with either finish; it just means that production will take more time because defective products will have to be remade. The need for extra steps in production with multiple different materials makes the coins more expensive as well.
Choosing Another Route
Black metal and precious metals like gold and silver look outstanding together, which is why we get so many requests to make coins this way. However, combining powder coating and electroplating isn’t the only way to achieve this specific dual plating effect. If you’re worried about the added production time and design constraints that come with ordering something like a black metal coin dual plated with gold metal, you could design something like this instead.
This coin is plated in black nickel, which is a precious metal plating like gold, silver or copper. Black and grey enamel paints are used to create the dark hues in the design, and the letters are dual plated with gold metal by sending the coins through electroplating a second time.
We also have options for metallic enamel that our customers will often use to create a similar effect as dual plating. If you’re hoping to get a black metal coin with high polish gold accents, gold metallic enamel may be the best option. At the end of the day, no matter what combination of powder coating, electroplating and colorfilling you choose, you can rest assured that our production team will create a product that meets the highest quality standards in the industry.
