The investment is built up using a ceramic slurry and stucco (fused silica).
The investment (ceramic shell) is built up in layers around the wax pattern and system by pouring over the pattern or by dipping the pattern into the slurry. Then the stucco is applied to the still ‘wet’ wax pattern to thicken up each layer and to allow a ‘key’ for the next layer to allow for cross bonding.
The wax pattern is now placed into a drying cabinet in which the temperature and humidity are carefully controlled. Drying time varies on the size of each individual sculpture.
Once dry, this process is repeated again and again, up to twelve times, or until the required thickness is achieved (this also varies on the size and shape of the job).