Using a high end CNC-mill the wax is carved out according to the 3D CAD-CAM file.
The waxes are assembled on a 'sprue'.
All casts are secured and ready for the next step.
Investment (special gypsum) is mixed for the molds.
Now these are ready to go into the kiln for 8 - 10 hours.
All air bubbles are removed with vacuum.
Gold or Silver needs to be melted and mixed thoroughly to be able to cast efficiently. Borax is used to make the mass smoother and more homogeneous.
After using vacuum to make the metal reach every cavity, the investment is dissolved and the cast comes out with the sprue.
Now the final part of the process begins with grinding, polishing, filing, polishing and more sanding and polishing.