The Production Process of Cast Copper Figure Sculptures

The Production Process of Cast Copper Figure Sculptures

1.Design & Drafting: Create detailed 2D drawings or 3D models of the figure sculpture, defining proportions, postures, and surface details based on the design concept.

2.Clay Mold Making: Knead and shape clay into the initial mold (primary mold) that matches the design, then refine details by hand until the form is accurate.

3.Reverse Mold Production: Cover the clay mold with materials like silicone rubber or plaster to make a reverse mold (secondary mold). Once the mold material cures, separate it from the clay mold to retain the sculpture’s shape.

4.Wax Pattern Casting: Pour molten wax into the reverse mold, ensuring it fills all details. After the wax cools and solidifies, remove it from the mold to get a wax pattern identical to the final sculpture.

5.Investment Coating: Dip the wax pattern in refractory ceramic slurry repeatedly, then sprinkle refractory sand to form a thick, heat-resistant investment shell. Let it dry completely.

6.De-waxing & Preheating: Heat the investment shell to melt and drain the wax (lost-wax process), then preheat the shell to high temperatures to enhance its strength and prepare for copper casting.

7.Copper Melting & Pouring: Melt pure copper or copper alloy (e.g., brass, bronze) in a furnace to a molten state (around 1,100–1,300°C), then carefully pour the molten copper into the preheated investment shell.

8.Shell Breaking & Rough Extraction: After the copper cools and solidifies, break the investment shell to extract the rough copper sculpture.

9.Grinding & Polishing: Use grinding tools (e.g., grinders, sandpaper) to smooth burrs, seams, and uneven surfaces of the rough sculpture. Then polish it with polishing paste to achieve the desired luster (e.g., matte, glossy).

10.Patina Treatment (Optional): Apply chemical solutions (e.g., sulfuric acid, ammonium sulfide) to the sculpture’s surface to create a protective and decorative patina (e.g., green, brown), which enhances corrosion resistance and artistic appeal.

11.Detail Refinement & Assembly: Hand-carve or touch up fine details (e.g., facial features, clothing textures) that may be lost during casting. If the sculpture has multiple parts, assemble them with welding or bolts.

12.Quality Inspection & Finishing: Check the sculpture for cracks, air bubbles, or shape defects. Make final adjustments, then clean the surface to complete the production.