Casting Metal Belt Buckles
- 1). Make a model of your belt buckle by carving a design into jeweler's wax. You can also make a model by pressing the wax into rubber molds instead of carving. Rubber molds tend to pick up more of the intricate details, and they are reusable.
- 2). Attache the model to a pour cup, which looks like a funnel and is used to pour the metal into the mold. Wax rods, called sprues, are attached to the model to allow gas and air to escape when the metal is poured in to insure that the metal will reach all of the small details. Then it needs to be places on a sprue base. The sprues and cup can be solid wax, since they will melt away, leaving the channels behind in the mold.
- 3). Make the mold by placing a metal flask, which is like a hollow pipe, over the model. The sprue base will have a rim to insert the bottom of the flask into. Both come in different size, so you can match them up to get a perfect fit. A mixture of refractory plaster is then poured into the top of the flask
- 4). Place the mold into a kiln that has been heated to between 1,000 and 1,250 degrees F. The mold must be placed in the kiln with the cup down to allow the melted wax to flow out. The mold must remain in the kiln until no more wax runs out. You will be left with a hollow mold that has retained all of the fine details of the original model.
- 5). Melt the silver or other metal and pour it into the cup to fill the mold. In order to get the metal into all the small places, the mold should be placed on a vibrating table or in a centrifuge. Let the mold cool completely, then break the mold. Finally, break away the pieces of the sprue and vents and polish the finished belt buckle.
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