Coating
Coating, also known as shell building, involves applying multiple layers of ceramic slurry and sand over the assembled wax patterns. The wax tree is repeatedly dipped into the slurry and then coated with fine refractory materials to build a strong ceramic shell. Each layer is dried under controlled temperature and humidity conditions before applying the next.
This process is repeated several times to achieve the required thickness and strength. The quality of coating determines the surface finish and structural integrity of the final casting. A strong and uniform shell is essential to withstand high temperatures during metal pouring.
