There is another technique in casting besides drain casting, it's called solid casting. As general drain casting is pouring the slip into the mold and when have certain thickness the remains poured into container back. While solid casting there is no remains, the slip is allowed to semi leather hard in the mold. Actually there is still remains to poured back, but very little just for making a foot rim (fig.4). Another characteristic is the drain casting for getting outer shape, meanwhile solid casting for getting outer and inner shape. Therefore the mold of solid casting could have a positive and negative shape.
Technically solid casting is more difficult. The bowl often stick to the mold. Usually before pour the slip, each mold is given talc powder evenly. Also the slip consistency must fluid enough. When the bowl start to separate to the mold, you can hit by hand the edge of mold for several times, until make a gap between bowl and mold.
The results of solid casting are more constant (shape and thickness), because drying process more even (have two shape molds: positive and negative). But anyway, there is form limitation for the technique. The form must be simple and wider into the top, such as bowl or cone. The form like vases wide then tapers back can't be done by this technique, because it will be stuck when lifted from the mold.
|1. Pour the slip|
|2. Wait until the certain thickness|
|3. Pour the slip back|
|4. Keep the mold in first position|
|5. Lift the positive mold|
|6. Keep the bowl in negative mold|
|7. Wait until the bowl separate|