Subtractive and Additive
Sculpture relies on two fundamental processes:
- Subtractive: carving. Stone or wood is removed. Every cut is irreversible. The form must fit within the initial block.
- Additive: modelling. Clay or wax is built up. The process is fully reversible and permits rapid revision. Clay is fragile, so models are usually cast in bronze.
The · Stone holds its compact mass, keeping limbs close. Tensile bronze can extend thin limbs freely into space.
Lost-wax casting
The cire perdue (lost-wax) method creates hollow bronze sculpture:
- In the direct method, the original wax model is destroyed. The cast is unique.
- In the indirect method, a master mould survives. This allows the artist to produce multiple editions.
Relief
Relief sculpture remains attached to a background plane.
| Type | Projection | Effect |
|---|---|---|
| Bas-relief | Shallow | Reads like a drawing in depth |
| High relief | Over half the depth | Figures appear almost freestanding |
| Sunken relief | Cut below surface | Sharp shadows in raking light |
| Rilievo schiacciato | Extremely flat | Creates perspective in millimetres |
Material Demands
Stone resists, wood follows grain, and bronze holds tension.
Common pitfall: treating bronze and marble versions of a figure as identical designs. Material dictates structure; a marble arm requires a supporting strut, whereas bronze extends unsupported.