Casting Slip
Casting slip is a specialized version of slip used specifically in the slip casting process. It is a liquid mixture of clay suspended in water, which has been adjusted to a suitable viscosity by the addition of deflocculants, such as sodium silicate. These deflocculants reduce the amount of water required in the slip, which improves the fluidity of the mixture and facilitates more controlled shrinkage during drying and firing, reducing the risk of cracking and deformation in the ceramic pieces.
The slip is poured into previously prepared plaster molds, allowing the clay to adhere to the mold walls while excess water is absorbed. This results in a uniform part formation with precise details and a solid structure. Often, additional deflocculants are added to optimize the consistency and stability of the mixture, ensuring that the reproduced pieces maintain their shape and detail throughout the drying and firing process.Interesting Fact
The invention of the pottery wheel, around 3000 BC in Mesopotamia, represented a technological revolution in ceramics. Before its appearance, ceramic pieces were molded by hand, which limited their symmetry and size. With the pottery wheel, they were able to create larger and more uniform objects in less time, which boosted mass production and allowed the expansion of ceramics as an industry in ancient civilizations.Helpful Tip
To obtain good results on the pottery wheel, it is crucial to learn how to center the clay correctly. Good centering is essential to create symmetrical pieces and avoid deformations during modeling. Regularly practice the centering technique, making sure that the clay is well balanced before you start throwing. Also, adjust the speed of the pottery wheel according to the stage of modeling, starting at low speed to form the base and gradually increasing the speed to refine details and achieve a smooth, even surface.
