Jewelry Casting Methods: Lost Wax, Die Casting, 3D Printing & More
Compare lost wax casting, centrifugal casting, vacuum casting, die casting, and 3D-printed casting for jewelry manufacturing.
Key Takeaways
Casting — pouring molten metal into a mold — is how most jewelry begins. The basic principle is ancient, but modern casting encompasses several distinct technologies suited to different production needs.
Lost-wax casting dominates fine jewelry manufacturing. A wax model is embedded in investment plaster, the plaster is heated to burn out the wax, and molten metal fills the resulting cavity. It handles complexity well — intricate filigree, undercut details, variable wall thickness — making it the default method for most fine jewelry.
Vacuum casting enhances lost-wax by pulling metal into the mold while evacuating air. This reduces gas porosity dramatically. Vacuum casting is the standard for platinum, which absorbs gas at its extreme pouring temperature, and for high-karat gold where any surface defect is immediately visible.
Centrifugal casting uses spinning force to drive metal into the mold. It excels at very small pieces — earring posts, tiny findings, delicate chains — where gravity alone would not provide sufficient filling pressure. The machines are simpler and cheaper than vacuum systems but require more operator skill.
Die casting injects molten metal into a reusable steel mold under high pressure. It is the fastest method, producing thousands of identical pieces per hour, but limited to low-melting-point metals like zinc and aluminum. The steel molds cost $2,000 to over $10,000, making die casting economical only at high volumes. It dominates the costume jewelry market.
Continuous casting produces raw material — wire, tube, bar, sheet — by pouring metal through a water-cooled shaping die. The solidified metal is pulled continuously from the die in lengths limited only by coiling capacity. Continuous cast material feeds chain-making machines, stamping presses, and findings manufacturers.
The choice of method involves balancing quality, speed, cost, and metal compatibility. A well-equipped jewelry factory typically operates several casting technologies, selecting the appropriate method for each order.