Building Hollow
Nearly all fired ceramic work is hollow. A solid mass cannot release steam and will break in the kiln.
| Technique | How it works | Best for | Limit |
|---|---|---|---|
| Pinching | Opening a ball with fingers | Small forms | Size limited by hand |
| Coiling | Rolled ropes blended | Large asymmetric forms | Slow process |
| Slabbing | Rolled sheets assembled | Geometric forms | Needs correct stiffness |
| Throwing | Raised on a wheel | Symmetric forms | Symmetric only |
Coiling imposes few limits on form. Build in stages to let lower walls firm up before adding weight.
Slabbing requires careful judgement of clay stiffness. Soft slabs slump, whereas dry slabs fail to bond.
Throwing is the fastest technique once mastered, but it only produces rotationally symmetric forms.
Joining Clay
Every join in clay follows four steps:
- Score both surfaces to increase contact area.
- Slip both surfaces with liquid clay to fill gaps.
- Press and blend across the seam so clay becomes continuous.
- Join at the same moisture level to prevent differential shrinkage.
Hollowing Solid Forms
A solid study can be cut apart, hollowed and rejoined at the leather-hard stage. Cut the form with a wire, scoop walls to an even thickness, then score and slip the halves back together.
Common pitfall: Choosing a technique by what looks impressive rather than what the form requires. Form dictates technique, not the other way around.