How to Make Simple Ring Castings

Lost wax gravity casting has been used for centuries to make basic rings. Casting may be done in your backyard or garage with very simple equipment. Our ancestors did this type of casting more than 2,000 years ago in primitive conditions, and so can you.

Things You'll Need

• 2 soup cans
• Wax
• Hot-carving tools (butter knife, screwdriver or electric soldering iron)
• Candle, alcohol lamp, torch or other small heat source
• Cold-wax tools (pocket knife, dental pick, awl, file)
• Campfire or charcoal barbecue grill
• 4 oz. 95/5 lead-free pewter or 95/5 lead-free solder
• Plaster of Paris
• Water
• Heavy welding gloves and protective clothing
• Slip-joint pliers or long tongs
• Full-face shield

Instructions

1. 

   Use hot-wax tools to carve a wax model of your ring. Remember that your casting will shrink 5 percent, so make your model a little bigger than the final ring will be. Make and attach the wax sprue, hanger and vent to your wax ring model by heating both wax surfaces to fuse them together, making sure all joints between the various wax pieces are sealed. The wax ring model attaches to the sprue as shown in the diagram. The cupped area of the sprue between the wax ring model and the hanger will make it easier to pour your molten metal. The hanger is then heated and pressed against the cupped surface of the sprue. Finally, a wax wire is attached between the bottom of the wax ring model and the hanger. When the wax melts away, this becomes a vent so that pressurized air can escape as you pour molten metal into the mold.

2. 

   Hang your wax model in the first soup can using molten wax to "glue" it to the can. Leave an equal amount of space on all sides of the casting.

3. 

   Mix Plaster of Paris and water according to package directions. Fill your soup can flask with this plaster mixture and allow it to cure for three days. The area in red in the image is the plaster that will surround the wax assembly.

4. Put your flask in the fire upside down to melt away the wax. Leave your can in the fire until there is no more smoke. Allow your flask to cool to room temperature.

5. Heat 95/5 pewter in the other can and pour it into your mold. 95/5 lead-free solder is the same metal but is often cheaper than 95/5 pewter. Once cool, remove your ring from the flask by breaking away the plaster. Finish your ring as desired after cutting away the sprue, using a pewter or wax-cutting blade on a jeweler's saw.

Tips & Warnings

• Jewelry wax makes the job much easier, but you may use candles once you melt them and remove the wicks. You may also use standard paraffin mixed with about 20 percent beeswax. Beeswax alone is a little too soft and expensive for lost wax casting, according to Gypsy Wilburn, who has used the lost wax casting method to make knife guards, pommels, bracelets, rings, ring knives and other ornaments. If you use a butter knife or screwdriver to carve wax, it will be useless afterward for other purposes. Heating will cause them to lose temper, making them bend. If you have a soldering iron, you won't need the other heating tools. After you pour the Plaster of Paris into the mold, place your flask on a vibrating surface, such as the top of a washing machine. Stand by so that it does not "walk" off the surface as it is vibrating, or place a folded towel around it. The vibrations will help remove any air bubbles, resulting in a better outcome for your lost wax casting.

• Lost wax casting needs to be done outdoors. When you burn the wax from the mold, it creates noxious smoke. Molten metal sticks to skin and burns deep. Wear heavy leather gloves, wraparound eye protection and full leathers when casting.

References

• Fred R. Sias, Jr. PhD.; "Lost-Wax Casting: Old, New, and Inexpensive Methods," pp. 115 to 120; Woodsmere Press 2005
• Chris Ralph; "Make Your Own Jewelry with Lost Wax Casting Methods and Techniques," Metal Casting Zone, 2009
• Gypsy Wilburn; Artisan Jewelry Maker and Industrial Blacksmith and Jewelry Maker; Carrollton, Ohio

Resources

• Photo: Silver Ring formed by lost wax casting (not an endorsement)