plaster is built up around the rod, the inside templated put on the rod, and the template is turned around until the plaster is in the shape of the core - then wax is applied to the plaster, and the outer template is put on the rod (same center, you see), and turned on the wax until the outer shape is formed. The wax is removed and cast----voila.
John, I suppose this is a method for casting hand-bells? At the
Whitechapel Bell foundry near London they use a slightly different
method for larger church bells. Still have the board and two
templates, but no plaster and no wax. The moulding material is
traditionally a mixture of loam, clay and horse manure, though today
they tend to use more chopped straw than manure, except for
demonstrations.
They make two shapes. One is the core, formed upright on the
baseboard. The other is formed with the shape of the outside of the
bell on its inside, and is made inverted. Both are allowed to dry
out somewhat before use. Any required lettering (and there is
usually some for church bells and commemorative bells) is made by
impressing metal letter shapes into the surface of the outer piece.
The outer is then inverted (using a small crane) and placed over the
core for casting.
Well rung hand-bells are a truly delightful sound, which I don’t get
to experience half often enough. I once had the job of specifying
all the ancillary fittings for a multi-purpose building that was to
be used for part of the time as a Christian church, and I included a
small peel of bells, specifying that they had to come from the
Whitechapel foundry. Pity it was axed in a sweep of cost saving.
Kevin (NW England, UK)