One of the crucial steps in ceramic making that craft lovers or potters cannot skip is "Biscuit Firing," or what craftspeople call Biscuit Firing. For beginners who have just entered the world of pottery, you might still wonder what this step is. Let me tell you, the principle of biscuit firing is much simpler than you think!
Biscuit firing is the process of firing ceramic pieces for the first time, while the clay body has not yet been glazed. It can be used for both low-temperature and high-temperature firing.
Many people might ask, "Why do we need to biscuit fire? Can't we skip it?" The answer is that biscuit firing makes the clay body or our pottery strong and retains its shape, preventing it from melting or becoming mushy when dipped in ceramic glaze. It also helps to enhance the colors of the clay body, making them clearer and more vibrant. Furthermore, biscuit firing also serves as a screening process, checking the condition of the clay to ensure there are no hidden cracks before moving on to the glazing process.
Techniques for successful ceramic biscuit firing without cracks
- Fire slowly and consistently: Do not rush to increase the heat too quickly, as a rapid change in temperature can easily cause the piece to warp or get damaged.
- Control temperature and time: Generally, the temperature for biscuit firing is around 750 - 850 degrees Celsius and takes at least 8 - 10 hours.
- Separate pieces by size: If the pottery pieces vary significantly in size and thickness, they should be fired in separate kilns to ensure even heat distribution.
- Allow pieces to cool in the kiln: Once firing is complete, do not remove the pieces from the ceramic kiln immediately. They should be left in the kiln for approximately 1 day to allow them to cool down slowly. This is because if hot pieces are exposed to cold air immediately, the sudden temperature change can cause the ceramic to crack and get damaged.