How to Cast Jewelry

Jewelry casting is a process of making jewelry pieces that involves the pouring of liquid metal alloy into a mold. It is usually referred to as lost-wax casting because the casting mold is created using a wax model that is melted away to leave a hollow chamber in the middle of the mold. The technique has been used for thousands of years, and is still widely used today by both master craftsmen and home crafters to make precise reproductions of original jewelry pieces. If you are interested in creating your own jewelry using the casting technique, follow these steps for how to cast jewelry.

1. Choose a model for casting. A model is a piece of jewelry that you want to make a mold out of. You may use any piece of your own jewelry that you are interested in reproducing.
2. Make a rubber mold using your model.
   • Purchase an unvulcanized rubber molding compound at your local arts and crafts supply store. There is a variety of molding compounds on the market and which you choose is a matter of personal preference, so you may want to experiment with making molds out of different types until you find one that you like the most.
   • Press your model into a suitably sized mass of the rubber molding compound. Be sure to surround the model entirely to ensure a complete mold for casting jewelry. The compound will be soft and pliable until you cure it, so there is no need to worry about damaging your model.
   • Subject the rubber mold to heat according to manufacturer's instructions in order to vulcanize, or cure, the rubber. The finished product will similar in consistency to a rubber bouncy ball.
   • Use a surgeon's knife to dissect the model out of the mold. Slice down the center of the rubber mold, length-wise along the model, creating a mold that opens like a book. Be careful at this stage not to damage your model with the scalpel.
   • Remove the model, being very careful to keep the mold intact, as any imperfections in your mold will result in a flawed wax casting.
   • Cut a shallow channel into each face of the mold, leading to the hollow chamber left by the model. The 2 channels should meet when the mold is closed together, creating a tunnel in which you will insert the syringe.
3. Inject the mold with melted wax. Use any type of crafter's wax that you purchase from an arts and crafts supply store. There are many different types of wax, and they each have different melting points, so experiment with a variety to find one you like the most.
   • Melt the wax in a double-boiler, referring to the package instructions for the appropriate melting temperature.
   • Use a medication dosing syringe to inject the melted wax into the closed mold, inserting the syringe through the divot channel you created in the jewelry casting mold.
4. Allow the wax to cool completely. Cooling times vary, depending on the particular wax you purchase. Follow package guidelines for cooling times.
5. Remove the wax model from the rubber mold. This will now be your model for the lost-wax jewelry casting process.
6. Make a stand for the model. Cut a thin stick of hardened wax, just large enough to support the wax model, and attach it to the model with melted wax.
7. Secure the wax model stand to the bottom of a casting flask, using more melted wax. The model should be propped up in the flask. It is ready for the jewelry casting process.
8. Mix the dry ingredients of the gypsum plaster-based investment mold material with water, as per manufacturer's directions.
9. Pour the investment mold mixture into the flask, surrounding the model completely.
10. Allow the investment mold to set.
11. Place the entire flask in a kiln set to approximately 1100 degrees F (2012 C). This will harden the mold and melt the wax away, leaving a hollow chamber in the center of the cast jewelry mold.
12. Remove the mold from the flask.
13. Pour the casting.
    • Place your metal of choice in a pouring crucible, then melt it inside a foundry. The melting temperature and time will be determined by the type of metal you are using.
    • Pour liquid metal from the pouring crucible into the mold through the tunnel left by the melted wax support stick.
14. Allow the metal to cool.
15. Tap the mold gently with a hammer to break away the mold and reveal the jewelry casting.
16. Buff out any irregularities on the jewelry piece using a metal buffing wheel.
    Refrence:http://www.wikihow.com/Cast-Jewelry