What casting method was used for Tibetan bronze Buddha statues in Qing Dynasty?

The production of metal Buddha statues generally goes through several important processes such as metal smelting, forging, carving, gold plating, polishing and painting. Namely, lost wax method and casting method.

Lost wax method: make a mold with wax and use molding materials externally to become a whole mold. Heating to melt wax, forming cavity mold, and pouring liquid metal. After cooling, die castings are obtained, which are widely used in Buddhist statues.

The earliest known lost wax castings in China are bronze cups and bronze cans unearthed in Xichuan, Henan Province in the late Spring and Autumn Period (a box-shaped apparatus for placing wine vessels in ancient times). After the Warring States period, the application of lost wax method gradually expanded, and it was used to make ding, seal, musical clock, Buddha statue, containers and ornaments in minority areas. The description of the specific process of the traditional wax loss method was first seen in Hu's Dongtian Collection in the Song Dynasty. The lost wax lifting department was established in the Yuan Dynasty, specializing in lost wax casting. In the long-term application process, the lost wax method has developed a variety of process types. In Ming and Qing dynasties, the method of drawing plastic into wax mold was called drawing wax.

Die casting method: "Die casting method" is the most widely used. Large Buddha statues are generally cast in one piece and then connected into a whole. First, make molds according to the existing objects or models. According to the size of the model, four wooden side plates of the mold are made, which are similar to a wooden frame. However, a movable plate should be left to facilitate fastening or opening after filling.

After that, lay the tied wooden frame flat, fill wet soil such as black peat around the model, fill it to one third of the volume of the wooden frame, and then tamp it. Then fill other gaps in the wooden frame with the same wet peat soil until it is flush with the top edge of the wooden frame. Then, loosen one of the four wooden frames, insert a sharp long knife, cut the mud around the model vertically, and take the model out of the mud, as if taking out two peach stones from Rende. After that, put the two pieces of mud on the model together and tie them tightly. After a day or so, separate the two pieces of mud and let them dry completely. Tie the two dry mud molds tightly, and leave a circular opening at the interface of the two molds to the center of the mold, which is convenient for casting metal. If the whole Buddha statue is cast, it is best to leave the pouring gate at the base of the Buddha statue to keep the surface of the Buddha statue smooth. The metal block solidified in the center of the clay mold is the finished product of metal art casting. Finally, the facial outline, eyes and clothing of the cast Buddha statue are slightly modified with a word "hug", and the surface of the cast statue is polished.