Tuesday, October 14, 2014

How To Make Double-Sided Coin Rings - #4

The next step in the creation of a double-sided coin ring is a process known as annealing the coin, in order to soften it. Annealing the coin is where you hold the coin in the flame of a propane torch until it just begins to glow. If the coin is copper, bronze or nickel-copper clad, you need to heat it up until it glows a bright cherry red. If the coin is Silver or 90% Silver it only needs to turn a dark red color. Generally, this step is done in a darkened or semi-darkened room in order to see the color changes more easily. A pair of locking forceps or jewelers tweezers are used to hold the coin in the flame.

Once the correct color is reached, remove it from the flame and let it cool naturally for a few seconds; then dunk it in a small container of water in order to finish cooling it to a point where you can safely handle it. (This annealing step will need to be repeated several times until the final shape is achieved.) Please note the annealing step will cause the coin to end up with a blackish (or brownish) scale after annealing. This is normal, and it will be used to create highlights during the final finishing and polishing step.

With the coin annealed, slip it over the small end of your ring mandrel. If you have drilled or punched a hole approximately 1/2" in diameter, it should just fit over the tip of the mandrel. Using your composition hammer (plastic, leather or nylon) begin hammering the edge of the coin, causing it to bend down and move down the mandrel. Do this lightly at first, because the coin is very soft. Try to hammer evenly around the entire perimeter of the coin. Gradually, the coin will begin to fold down closer to the mandrel, and will resemble a cone shape. As you hammer the coin, the metal will "work harden" and eventually you will need to repeat the annealing step. After you remove the coin the first time, you will want to file the cut edge until it is fairly smooth all around. This will keep the coin from splitting as you continue forming it down the mandrel.

Keep repeating this hammering step and annealing step until the outside perimeter of the coin is nearly touching the surface of the mandrel.

Anneal the coin once more. This time when you put it on the mandrel; place it so the cone shape is the reverse of how you have been placing it on the mandrel. That is with the large end of the cone facing up instead of down.  Now, keep hammering the perimeter of the coin until it flattens against the outside of the mandrel. Keep in mind you may have to anneal it again before it can be flattened completely against the mandrel.

In the next posting I will explain how to finish the coin ring.


No comments:

Post a Comment