rōgata 蝋型

Also rōgata chūzō 蝋型鋳造, rōgata imono 蝋型鋳物. A method of metal casting known as the lost-wax technique. Frequently used in Japan for casting bronze statues, which were often gilded. See *kondō 金銅. First, a basic model of the desired vessel or statue was made in clay or plaster. This was then covered with a layer of beeswax mixed with pine resin, which was moulded to the required shape and engraved with surface details. An outer layer of soft clay or plaster was then applied over the wax. The outer clay mould and the inner model were secured from the sides, or at the front and back, using fragments of metal *katamochi 型持 or metal pins *kōgai 笄. The entire construction was then fired, causing the mould to harden and the wax to melt and run out. Melted metal was poured into the gap left by the wax, between the outer mould and the inner core. When the metal had cooled and hardened the statue was removed from the inner and outer moulds, and the marks left by the pins were repaired. See *ikake 鋳掛.
Solid metal statues were produced from a model made directly from wax without an inner core. This model was then covered, fired and cast.
The lost-wax method allowed free modelling, as the wax surface was very easy to work, and was suitable for casting complex forms and intricate detail. It produced a beautifully smooth, sculptural surface in bronze.
In Japan the lost-wax method was used from the 6th century, beginning with small gilt-bronze statues of the Asuka and Nara periods such as the Shō kannonzō 聖観音像 in Yakushiji 薬師寺, Nara. Most of Japan's early bronze statues are believed to have been made by this method. Its use continued during and after the Heian period, and the same technique was used to make small decorative carvings *netsuke 根付 in the Edo period.