Dewaxing is done using a steam-dewaxing autoclave or flash fire furnace. Putting the shell in a steam autocalve and rapidly heated. So that the wax will be melt and run out through the gate and pouring up under high temperature. The ceramic shell molds must be fired to burn out the last traces of pattern material and to preheat the mold in preparation for casting. That is why investment casting also called “lost wax casting”.