How to Cast Fire Brick
- 1). Combine four parts fire clay with two parts ball clay and four parts either crushed coal or grog and mix thoroughly with the hands or by stomping it with the feet, then form the clay mixture into standard construction-brick-sized rectangles.
- 2). Set the wet fire bricks in a hot, dry location and allow them to dry for two days, then turn them over and allow them to dry for two more days.
- 3). Place the bricks into a ceramics kiln and set the heat to a low setting and allow the bricks to bake at a temperature below 800 degrees Fahrenheit for two days while the last of the water content is burned off.
- 4). Turn the kiln up to 2,552 degrees Fahrenheit and fire the bricks at that temperature for two days, then turn the kiln off and leave the bricks inside to allow them to cool at their own rate, about three to four days.
- 5). Remove the bricks from the kiln.
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