< ANIMAL & INSECT WAXES
VEGETABLE WAXES
Extracted from plant matter, vegetable waxes are generally characterised by their hardness and a low rate of expansion when heated (conversely, softer waxes tend to have higher expansion rates). A low expansion characteristic or CO-EFFICIENT is of some value in the casting process – wax patterns retain their dimensional accuracy especially in warm weather, and investment moulds are less likely to rupture in the kiln as the contained wax design expands under heating.
CARNAUBA wax is commonly available vegetable wax. Extracted from the leaf of the Copernica Cerifa wax palm, carnauba is the among hardest of the natural waxes, with an upper melting range of about 195°F (90°C), compared with bees wax which has an upper metlting range some 45°F below this. Adding carnauba wax into a blend will usually harden the product and raise it’s upper melting range. Being an exceptionally hard and resistant wax, carnauba wax and similar wax blends make for very good protective finishes when applied to sculptures. This type of blend is especially useful for use on artworks those situated in adverse out of doors environments.
Other vegetable waxes include, Borneo, candelilla, Chinese, Japanese and ocricury. Japanese and Chinese waxes are based on variations of the Rhus plant species. Softer than carnauba wax, these waxes can be variously used to adjustboth the upper and lower melting ranges of a blend.
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