Burning out the wax is pretty dramatic. great for pyromaniacs.

The mold shells are blasted with 900 degrees of heat as quickly as possible. The speed is essential, if the shell is heated too slowly the wax expands inside the mold and causes cracking.

You want the heat to liquify the outside layer of wax instantly so that it flows out of the mold before the inner layers of wax have time to expand.

A wet tray under the kiln collects any wax that is not vapourised and burned during the process.