How to Make a Cast Mold for Making Gold Jewelry

There are several different methods for making a cast molding for gold jewelry. The method in this article is called the lost wax method of mold making. In this method you will need to first carve your creation in wax. Be as creative as you wish and include all of the intricate details that you need in order to make your piece of jewelry as unique as you are. There are few gifts more personal--or more special--than hand-made gold jewelry!

Difficulty: Moderate

Instructions

Things You'll Need:

• Large candle
• Metal can
• Blow torch
• Styrofoam cups
• Carving tools
• X-acto knife
• Faster Plaster
• Wire coat hanger
• Petroleum jelly
• Paper towels
• Microwave oven

1. Buy a large candle or block of wax. Melt the wax inside a metal can using your blow torch and pour the wax into a Styrofoam cup. Once the wax has cooled peel away the Styrofoam cup so you have a block of clean wax. (The reason for melting the wax is to remove any air bubbles that were left in during the original manufacturing process.)

2. Carve your piece of jewelry out of the wax. Carve all of the details into your wax replica that you wish to appear in your final piece of jewelry. Take your time because what you see on the wax piece of jewelry will be exactly how it will appear once cast in gold.

3. Mix enough Faster Plaster to more than cover the wax version of your jewelry. Pour half an inch of the Faster Plaster into a Styrofoam cup. Tap the sides of the cup as you pour the plaster to keep air bubbles from forming. Place your wax jewelry into the plaster with the front side of the jewelry facing down into the plaster. Do not push your wax piece down into the plaster but allow it to "float."

4. Cut a piece of metal coat hanger and bend it in such a way that one point of the hanger touches the back of your wax piece and the other end of the hanger remains outside of the Styrofoam cup. Coat the metal hanger with petroleum jelly. Set the hanger piece in place so that it touches the back of your wax piece and then pour another inch or two of plaster into the cup, completely covering the wax piece. Tap the cup gently to remove air bubbles in the plaster. Allow the plaster to dry for at least 2 hours.

5. Remove the piece of metal coat hanger. This should leave a hole in your now mainly-dry plaster that goes all the way down to your wax piece. Peel all of the Styrofoam off of your plaster and invert the plaster over several sheets of paper towels. Place in a microwave and "cook" on high for 3 minutes. This should cause all of the wax to melt and run out of the hole left by the coat hanger and onto the paper towels. The microwaving will also finish the curing process on the plaster.

6. Shake the plaster, wearing oven mitts, to make certain that all wax has dripped out. Reheat for a minute or so longer and rotate the mold to make sure that all wax has come out. Turn the mold upright and allow it to cool. Your cast mold is now ready.

7. Pour your molten gold into the hole left by the coat hanger, tapping the mold as you do so to ensure that there are no air bubbles in the gold. Allow to cool for half an hour and then carefully chip away the plaster to reveal your cast gold piece of jewelry.

Tips & Warnings

• You may want to carve a slight funnel-like opening at the top of your mold to help you pour your melted gold into the small hole left by the coat hanger. If possible you may wish to put two pieces of coat hanger into your plaster with each one touching the back of your wax piece if it is large enough. This will allow you to pour your gold down one hole while air escapes out of the other. If you have only one hole you must tap the mold fairly firmly to remove any air bubbles that may be trapped in your gold.
• Always wear eye protection when melting and pouring gold or any other metal.