GENESIS OF A SCULPTURE
To understand the genesis of a carved sculpture, you can look at the film The Genesis of a Sculpture, by Adam-Tessier, directed by Olivier Clouzot and Julien Pappe (13 minutes, black and white), part of The Roland Collection of Films on Art (www.rolandcollection.com, free clip, small fee for complete film download).
A very useful book to find definitions of sculpture techniques is:
Jane BASSETT and Peggy FOGELMAN, Looking at European Sculpture. A Guide to technical terms, The J. Paul Getty Museum in collaboration with The Victoria and Albert Museum, 2007.
The authors kindly allowed me to quote some of their entries. I am happy to thank them.
A more or less exact reproduction of an existing sculpture.
Historically, the term was associated with common workshop practices and did not bear its present-day pejorative implications. For instance, copies or REDUCTIONS of ancient works of art were executed by some of the most skillful European sculptors from the Renaissance on and were valued by collectors and antiquarians. Artists produced copies of their own work for different clients or supervised the copying of their sculptures by studio assistants. Patrons unable to obtain an original work from a particular sculptor might commission a copy of the work from a different artist. Copies were usually produced without the intent to deceive. A reproduction that was deliberately made to deceive collectors or potential buyers is more accurately termed a "fake" or "forgery". (p. 25)
(French, "Rough Draft")
A stage in the development of a finished sculpture, usually of stone or wood, in which the basic forms, volumes, and essential elements of the composition have been established, but the details have not been carved and the surface is rough and unpolished. The term "ébauche" signifies an unfinished sculpture, at a preliminary stage of its execution. It should not be confused with a preparatory study for a sculpture. Compare MODEL. (p. 30)
A reproduction of an existing sculpture on a larger scale. See REDUCTION. (p. 33)
See SKETCH and MODEL.
A three-dimensional preparatory model, usually in clay or wax, which represents on a smaller scale the subject and composition of a sculpture to be executed on a larger scale in a more permanent and expensive material. A maquette is generally more finished and refined in its details, and represents a more advanced stage of compositional development, than a SKETCH. A maquette may serve, and be synonymous with, a presentation model if it is used to secure approval before work on the final sculpture is undertaken. (p. 56)
A preliminary version of a projected sculpture, usually executed in an inexpensive material. Models are typically created through an additive process of building up and manipulating a sculptural material, such as clay or wax (see MODELING). However, carved wood models, created by cutting away material, were used in northern European countries such as Germany.
A model is a preparatory work, made to facilitate the design and/or execution of the final sculpture. In English, the term generally applies to all such objects, but other European languages have a more specific vocabulary to designate the model's particular function and its consequent degree of finish and type of surface treatment. Thus the English term "model" encompasses the Italian "bozzetto" and "modello" and the French "esquisse" and MAQUETTE.
Models serve a variety of purposes within the sculptor's studio. In the same way that painters use drawings, sculptors use models for the rapid notation of their ideas in three dimensions (see SKETCH). Models serve as reference tools for the translation of a composition to a larger scale or more permanent material. For example, artists may use plaster POINTING models to reproduce a composition in stone. Wax models are employed in the process of casting metal sculptures (see LOST WAX CASTING). Presentation models, in which all the details of a projected sculpture have been fully worked out, can be shown to a patron to gain approval for the final work or to a prospective client in the hopes of securing a commission (see MAQUETTE). In such instances the model may be painted or GILDED to approximate the material of the projected sculpture. (p. 60-61)
The negative impression of a form into which a sculpting material is poured or pressed.
Types of molds include:
- intaglio molds, which are carved into stone or ceramic that is resistant to heat;
- piece molds, which can be taken apart without damage to the model, the cast sculpture, or themselves;
- waste molds, which must be broken away to reveal the cast sculpture and therefore can produce only a single casting;
- sand molds, used in SAND CASTING, which are relatively easy to make but must be remade after each use;
- flexible molds, made of gelatin (and today of various elastic polymers such as silicone), which can be used in place of piece or waste molds but may deteriorate;
- and finally, mother molds, which hold all the sections of a piece mold in proper alignment.
Molds allow for the production of one or many copies of an original model or sculpture. Essentially all major European metal sculpture from the fifteenth through the nineteenth century was cast (or, in the nineteenth century, electrotyped) into molds. Clay, wax, plaster, stucco, bronze, brass, lead, zinc, silver, and gold can all be cast into molds.
Mold seams are raised lines, caused by the fine space that exists between the mold sections, which remain on the surface of a piece-molded object. Mold seams are generally removed to hide signs of the sculpture having been mold-made. (p. 63)
A reproduction on a smaller scale of a work of sculpture already in existence.
Reductions as well as enlargements were made by using calipers or proportional compasses to transfer measurements taken from the original sculpture (and then either decreased on increased in accordance with mathematical proportions) to the reproduction. More sophisticated mechanical instruments, such as the Colas machine, used for reductions as well as enlargements, became popular in the nineteenth century. See POINTING. (p. 76)
SKETCH or SKETCH MODEL
A small, preliminary version of a sculpture executed in clay, wax, or other inexpensive, pliable material, which the artist uses to work out and record the forms, proportions, and composition of a projected work in a more permanent medium. Also know by the term "esquisse" (French) or "schizzo" or "bozzetto" (Italian).
Because it represents an early stage in the creative process, a sketch may differ substantially from the final sculpture. A loose, energetic handling of the material - which sometimes preserves the sculptor's fingerprints and tool marks - is characteristic of the sketch. Beginning in the sixteenth century three-dimensional sketches were collected and valued as independent works of art, at first because of their association with great masters and later because of a changing aesthetic that prized the sketch's immediacy and its direct recording of the sculptor's initial thoughts. See MODEL and MAQUETTE. (p. 83-84)