In the previous article, we talked about the workshop where all jewelry production begins and wax models (waxes) are created, which are soldered onto a jewelry “Christmas tree.” After the “Christmas tree” is ready, a process called “lost wax casting” begins. It begins as follows: take a flask, i.e. a special cylindrical device made of steel, and is installed on the Christmas tree. The flask is necessary in order to hold the molding mixture, in our case, jewelry plaster, while compacting it in order to subsequently produce a casting mold.
Next, the flask is wrapped to prevent the plaster from leaking out, because The jewelry molding mixture is made on the basis of water so that in the future it will be easier, without any damage, to remove the finished jewelry tree from silver.
The flask is placed in a molding machine, where a gypsum mixture is poured into it, which is evacuated and vibrates to avoid the appearance of excess air bubbles, because If they are present, the plaster mold may burst or crack. The mold is pulled out and left for an hour for the plaster to thicken. The above procedure in jewelry manufacturing is called molding (molding).
After the plaster has hardened, the flask is put into the oven, where the temperature (in about 12 hours) gradually reaches 750-800 degrees so that the wax does not burn, but melts, flowing out of the plaster. Thus, after melting the wax, only a cast of the details of the future product remains in the plaster.
Next, the investment ring is moved to a casting machine, into which the sample is poured, certain settings and temperatures are set, and silver is poured into the plaster. Interesting fact: the thinner and more “openworked” the product, the higher the melting point should be. Then the mold is cooled and placed under running water to wash away the plaster. As a result of all these processes, the craftsmen receive a Christmas tree with finished silver products, which is cleaned of plaster and all products are removed from it either manually or using pneumatic scissors. Finished products are placed in tumbling to completely clean them of dirt and plaster residues.
