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- China's "King of Bells" in the Beijing Ancient Bell Museum. Weight 46.5 metric tons.
THE CASTING OF BELLS IN CHINA
The casting of large bronze and iron bells in ancient China was a labour intensive process, involving two basically different methods.
With one method, a large pit was dug in the ground and a foundation laid. A smooth core was then made of lime and mortar and dried. This was covered with a mixture of ox fat and beeswax in the thickness and shape of the desired bell and then engraved or moulded in relief with designs and text. A layer of thick mud paste (a mixture of clay and charcoal powder) was then placed on the wax model of the bell. Next, heat was applied baking the mould and at the same time causing the wax and fat to melt and drain out. The bell is then cast by pouring molten metal into the space vacated by the wax and fat between the core and mould. This is known as cire perdue or lost wax process. Huge amounts of metal were melted in nearby furnaces which had earthen trenches lined with red-hot charcoal, declining into the cavity just mentioned. The metal flowed into the mould and the bell was thus cast. In the case of smaller bells, the molten metal was carried to the site in a kettle on poles and poured into the mould. This often caused defects or cold shuts if each pouring was not done in rapid succession.
Sometimes bells were cast from two half sectional moulds or several small sectional moulds fitting together. This method made the engraving of designs easier, but the task of
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