a method and an apparatus are provided which allows the safe and inexpensive extinguishing and cooling of flaming wax emanating from an investment casting flash fire dewaxing furnace . investment mold structures are disposed within individual cups which direct flaming wax material downwardly through individual openings in the furnace floor . flaming wax is then extinguished within an extinguishing chamber by a stream of non - aqueous inert gas . the process makes flash fire dewaxing of investment mold structures efficient and safe and provides for easy recycling and reuse of the wax because it is not contaminated with water or other contaminant materials .