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ANTIQUE PAINT FINISHES
The painting of metal casts by the Egyptians, Greeks and Romans to produce a variety of decorative effects (including flesh imitations), is well documented – though it is rather difficult to know how successful painting methods were as most surviving classical works with a painted finish now have little more than a trace of their original coating left intact [ref 1].
Paints can be used to imitate an antique PATINA effect on copper alloy casts. One recorded method [ref 2 ], requires the cast’s surface to be first prepared with a mild ammonia solution, which imparts a suitably receptive surface for the paint. After the ammonia solution has dried, a PRIMER COAT is painted over the cast and also allowed to dry before over spraying the cast a matt enamel paint. When the enamel paint has dried and hardened, an appropriate hue of oil borne PIGMENT can be worked into the surface of the sprayed enamel paint. Once dried, the coating can be laquered and polished to produce an antique effect ‘patina’.
FAT TEMPRA
The paint technique described above produces a relatively uniform ‘patina effect’, imitating the finishes associated with traditional decorative bronze and brass designs. More varied and ‘painterly’ finishes can be obtained on cast copper alloys using more familiar artist’s pigments. TEMPRA GRASSA, or FAT TEMPRA is a very effective BODY for carrying paint pigments for use on metals. Fat tempra body is composed (variously) of, egg yolk, dammar, resin varnish, linseed oil and rabbit skin size (LEAN TEMPRA contains gum arabic in preference to egg yolk). The egg yolk component in the tempra functions as an ‘agulitinant’ (BINDER), hardening to a permanent and resistant finish which both protects the underlying fabric of the cast, and also has sufficient long term stability to maintain the colour values of an enormous range of added pigments.
Tempra is loaded with a chosen pigment, then applied to the primed metal surface of the cast to suit. Prior to modern ‘off the shelf’ products, a coating of white gesso or red bolus earth was considered best for priming cast copper alloys prior to tempera painting. Tempera is today available as pre-packed tubes of paint, though many artists working with this medium will still prefer to prepare and use their versions of their own making [ref 3 ].
OIL PAINTS >
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