INVESTMENT CASTING PROCESS

Step 1:  Make the wax injection tooling.  The first step in the process is to make a wax pattern using an injection molding type process.  One wax pattern must be produced for each casting that will be shipped.  Therefore, injection molding tooling must be produced.

Step 2:  Inject wax patterns.  One for each casting you will ship.

Step 3.  Assemble multiple wax patterns together to form a “tree” or mold.

 Step 4:  Create a ceramic shell around the wax by repetitively dipping the wax mold in to ceramic slurry and then a bed of sand (called stucco).  Between each dip, the mold is allowed to dry.  This is the investment process that gives investment castings their name.  As the coats of ceramic build up on the mold, the ceramic shell becomes thick enough to be suitable for metal pouring.

Step 5:  Remove the wax from the mold by melting it out of the ceramic shell that surrounds it.

Step 6:  Fire the mold at approximately 1900 degrees F.  This cures the ceramic to give it strength and vaporizes any wax residue that remains after the wax was melted out.

Step 7:  Pour molten metal in to the mold.  After the metal solidifies, the mold has the exact same shape as the wax tree that was melted out of the ceramic shell in Step 5.

Step 8:  Remove the shell from the metal mold, then cut the individual parts off the mold and grind off the remnant of where they were attached to the mold.

Step 9:  Finish and inspect the individual parts to prepare them for shipment.  The parts may need to be straightened, heat treated and have protective or decorative finishes applied.  Then they are inspected and shipped.  The result is metal parts that are duplicates of the wax patterns.