What does bell founding

The casting of bells is called "bell founding," and a most important part is the metal that is used, called "bell metal." The metal must be just hard enough to have plenty of resonance, or ring, but it must also be flexible enough not to break easily from vibration and from being struck.

A mixture of copper and tin, with varying amounts of zinc and lead, is considered the best bell metal. More copper is used in large bells, however, than in small ones. Other metals such as iron, nickel, and steel do not make good bells, and the expression that is often heard, "as sweet as a silver bell," does not mean that bells are ever made of silver, for silver has very little "ring." When the bell is cast, the molten bell metal is poured into a mold that is shaped like the bell.

The inside mold is solid, and is called the "core," for it shapes the inside of the bell. The outside mold is called the "cope," and it shapes the outside of the bell. The shape of a bell is of great importance, for if it is too narrow, or too broad, the tone will be poor and lack carrying power. When the bell has cooled, the molds are taken off, and then tuning and finishing begin. The bell is tuned by shaving off bits of metal, as it is slowly turned around and around. This must be done very carefully, because once the metal is shaved away it cannot be replaced.