Thursday, 21 June 2012

The Collas Machine / appareil réducteur

 The Collas Machine

Invented in 1836 by  French engineer Achille Collas, this machine uses a pantograph system to make proportionately larger or smaller duplications of a sculpture. The concept can be traced to ancient Greek and Roman artists, who wanted to reproduce the perfect proportions of the human figure in their sculpture. Their method was called pointing, which meant that measurements of the desired figure were taken, then proportionally increased or decreased on a model. Collas machines often look like lathes. On one turntable sits the plaster model. On a second turntable, connected to the first, sits a clay or plaster "blank" that has been roughly shaped to resemble the model but on a larger or smaller scale.
The Collas machine keeps the model and the blank in the same orientation as the technician uses a tracing needle, linked to a sharp cutting instrument, or stylus, to transfer a succession of profiles from the model onto the blank. Gradually the blank is worked so that it becomes a larger or smaller duplicate of the model.

Rodin and his skilled associate Henri Lebossé collaborated closely on reductions and enlargements

Around 1836 Collas developed a new machine permitting the mathematically precise reduction or enlargement of sculptural objects in full relief. Three years later he demonstrated its abilities by producing a two-fifths size reproduction of the Venus de Milo. His device became the main vehicle for the mass replication of antique and modern sculptures catering for a growing demand for inexpensive luxury items to decorate bourgeois interiors. In 1838 he entered into partnership with the manufacturer Ferdinand Barbedienne (1810-92) and the firm of Collas eventually employed around 300 workers and produced over a thousand bronzes each year. They reached an international audience with an acclaimed exhibit at the Great Exhibition of 1851 in London, which featured as its centre-piece a half-size reproduction of Ghiberti's principal door to the Baptistery in Florence. Even after Collas's death in 1859, his 'method' remained the mainstay of Barbedienne's enduring commercial success throughout the latter part of the nineteenth century.

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