Lost wax and lost foam are two very similar methods used to make very accurate metal castings for all kinds of different alloys. The first is called lost wax or investment casting. This process begins with the production of a heat disposable wax pattern made by a precision tool. This is what the shape of the finished product will look like. After several wax patterns have been created, they are placed onto a gating system for the molten alloys to flow. The Patterns are then covered with a thin layer of a sand and a ceramic mixture. The wax is melted out using some form of heat and the ceramic mold is then cured in an oven for several days. Finally the mold is ready for the pouring of the specific alloy. Once the mold is broken; your product is now ready for inspection or finishing.
The lost foam method is very similar to the lost wax method. First a precision tool makes the pattern out of expendable polystyrene beads instead of wax. The patterns are assembled to a gating system and the pattern is covered with a wash coat. Fine sand is then compacted around the pattern and the mold is ready for casting. There is no need to cure the mold in an oven which may take several days. Also there is no reason to remove the foam before the casting process because the molten metal simply evaporates the foam through the walls of the sand mold. Once the metal or alloy is poured into the mold, the mold is broken and your product is complete. .
The lost foam method is a cheaper and faster process of creating a mold of casting. With the wax method, the wax needs to be removed from the mold, and then the mold needs to be cured in an oven for a few days. Each step takes time and the curing process costs a lot of money. With manufacturing time is money. Therefore, in less your finished product needs to be very precise with its dimensions, the lost foam method is the most efficient.
Hitchiner is the leading supplier for floatwall panels which are found in jet engines.