Cast Glass

Process & Production

Lost-wax cast glass.

After shaping, the wax former (aka ‘positive’ ‘model’) was set up for investment casting. A frame was constructed around the model. Refractory plaster was mixed and poured into the mould box, over the former and left to set. After setting, the mould box was removed. The plaster mould was set up over a steamer to melt the wax out of the mould – leaving a void where the wax once was. The waste wax was then reclaimed for subsequent use.

The cleaned plaster mould was placed into a cold kiln, with glass blocks/cullet loaded into a reservoir above the mould prior to firing.

After kiln-firing, the plaster was moved, the glass cleaned, cut, shaped, ground and polished.

The refractory plaster mix used was:

Per 1 litre of water: 700g plaster 700g flint (or quartz)