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The Rolls Royce ‘Spirit of Ecstasy’. The world’s most recognised car mascot has evolved since the first sculptures nearly 100 years ago. Polycast Ltd are proud to have played an integral part in the evolution and restoration of a heritage icon.
- Exact Wax replicas of the item to be cast are produced by injecting hot wax into a metal mould.
- The wax replicas are assembled onto a specially designed wax tree. The tree is designed to incorporate the wax channels, to ensure the molten alloy flows into the moulds efficiently.
- The design ensures the molten metal reaches every area of the mould to produce the specified dimensions and metallurgy.
- The wax tree is dipped in ceramic slurry, which is then coated with zircon sand in a dedicated coating cabinet.
- The coated wax trees are dried in humidity controlled air cabinet.
- The dried trees are put into an autoclave where pressurised steam melts the wax out of the ceramic moulds leaving an exact mould to create the cast in.
- The ceramic moulds are forwarded to the foundry where technicians have checked the composition and temperature of the metal prior to casting. This metal is then introduced to the moulds.
- Once the metal has cooled sufficiently the ceramic shell is vibrated off the cast product by the use of a pneumatic knockout machine.
- Any remnants of the ceramic mould is removed by stainless steel shot in a rotary peening machine.
- The metal tree containing the cast products have the stems sawn off by a carborundum wheel.
- The cast products are sent to the finishing department where they are machined, heated treated, polished and assembled as required.