Bellmaking
From Free net encyclopedia
Bellmaking or bellfounding is the craft of creating bells in a foundry. A practitioner of the craft is called a bellmaker or bellfounder.
The term usually describes large bells forged for use in churches, clocks, and public buildings. There are two types of bells to consider - the bells which are played by striking with a clapper or stick and the bells which form the final portion of brass instruments.
Bells which are rung are usually made by casting bronze into forms of a size appropriate for the pitch the bell is intended to produce. Other materials sometimes used are brass or iron.
Fine tuning of cast metal bells is the most difficult part of the process. After being cast, the bell is put on a lathe to smooth mold marks and for removal of a precise amount of material to produce a true tone. Small cheap bells, of course, do not undergo these steps. Bells are used often in sets in hand bell choirs, chimes or carillons and so must be well tuned in order to produce pleasing chords.
Bellfounders may create one large bell (such as the Liberty Bell). The largest bells weigh several tons and present certain difficulties in safely moving them much less tuning them. The largest bells often are made to be played by swinging only the clapper instead of the entire bell as swinging such large bells would cause structural problems for the towers they are housed in.
In making the bells of brass instruments, a person lays out a pattern and shapes sheet metal into a bell-shape using templates, machine tools, handtools, and blueprints. The maker cuts out the bell blank, using hand or power shears. He hammers the blank over a bell-shaped mandrel, and butts the seam, using a notching tool. The seam is brazed, using a torch and smoothed using a hammer or file. A draw bench or arbor press equipped with expandable lead plug is used to shape and smooth the bell and bell neck over a mandrel. A lathe is used to spin the bell head and to form a bead at tip of bell head. Previously shaped bell necks are annealed, using a hand torch to soften the metal for further bending. Scratches are removed from the bell using abrasive-coated cloth.
References
- van Bergen Bells history
- The historical development of bell tuning
- Bell Foundries
- Trevor S. Jenning. Bellfounding. Hyperion Books (December, 1989). ISBN 0852639112
- John Llewellin. Bells & bellfounding: A practical treatise upon church bells. Kingsmead Bookshop, 1969. ASIN: B0007KB71Y
- XYZ. Bells & bellfounding: A practical treatise upon church bells. Albert Saifer; Facsimile edition (1984). ASIN: B00071V8OE