Foundrymen
Lost Wax Casting
Many of Soane’s metal lighting designs are made by a workshop in Hastings, on the South coast of England, that is highly specialised in the technique of lost wax casting. Traditionally used by artists to cast bronze sculptures, the art of lost wax casting allows for great freedom and flexibility of form while retaining exceptionally fine details and beautifully smooth surfaces. It is this detail and decorative nature that brings designs to life, and the reason why workshop manager Alan is so passionate about this traditional technique. With expertise and experience dating back more than 30 years, Soane has collaborated closely with Alan since 1997.
Made from solid brass, every cast metal lighting design passes through the hands of numerous craftspeople, epitomising the great expertise and extraordinary skills of the workshop. The process begins with their in house artist, Mark, who draws and sculpts an original pattern (or ‘master’), developed from drawings created by Soane’s design engineers.
A rubber mould is created around the master pattern and used to cast a wax version of the final design – a process that foundryman Rob learned from Alan more than a decade ago. This technique leaves a void, which is filled with hot wax, preserving all the exquisite detail of the master.
Once the wax has set, Rob works like a sculptor, finessing the details of the piece to ensure it is a perfect replica of the finished piece. Each individual element is then carefully welded to a ‘tree’, which ultimately allows the molten metal to reach every detail of the design, while restricting the formation of air bubbles in the metal, ensuring it’s as structurally sound as possible.
Rob selects the correct sized flask in which to house the ultramarine tree – being too large will lead to wastage and reduce the number of designs he can bake at once; too neat and the plaster will blow, forcing him to begin the process again. The flasks are bound and the plaster of Paris is poured around the tree.
Once the plaster has cured and the flask is unbound, they are baked for 16 hours in an oven – the holes allow unwanted moisture to escape and the wax melts and is lost (giving the process its name).
Molten brass is then deftly poured into the plaster moulds. It is here that Rob’s expertise really shines. Judging the temperature of the metal by eye alone, Rob’s innate understanding of the nuanced colour changes the brass undergoes to reach temperatures of up to 1,000 degrees Celsius allows him to pour the metal at the optimum moment, dictated by the demands of each design. The great physicality of this process combined with the quickly changing temperature leaves only one window of opportunity to fill each mould.
After just 30 minutes of cooling, the moulds are submerged in cold water and the plaster removed, leaving brass trees to appear.
The components are then ready to be cleaned and dismantled into individual parts before being brazed, polished, aged, fettled and soldered.
The final components are carefully assembled and the complete design is brought to life, all before the patination and wiring processes begin in Soane’s own Leicester workshop.
At Soane, we’re proud to work with this network of brilliant craftspeople who continue to pass down their knowledge and skills. After more than a decade of honing his craft, Rob is now proudly teaching apprentice Thomas the techniques he has learned from Alan, securing the art of lost wax casting here in Sussex for another generation.
