- 1). Mix the plaster with talc, sand, sodium silicate and water to form a liquid substance.
- 2). Pour the liquid into a spray bottle and spray the mixture on polished brass pattern halves. The liquid needs to be at least 1.5 mm thick to form a sturdy mold.
- 3). Dry the liquid for about 15 minutes in the mold. After this, extract the mold and dry it in the oven for 30 minutes at a temperature of 130 to 150 degrees Fahrenheit.
- 4). Pour the molten aluminum in the plaster molds.
- 5). Break the plaster molds and wash the aluminum to remove any signs of the plaster casing.