1.
A wax model is made, usually over a sandy, clay core that is shaped roughly
like the finished product. This example shows a fairly large Buddha
image. The flowing robes are typical of the Mandalay style. Notice the
little rolls of wax on the bottom left- this is all hand made! The core
usually stays inside the finished image.
2.
The wax image is studded with nails, and the wax is then covered
with a clay plaster. The plaster goes on in several coats. When it dries,
the result is a negative image - what you can see in this picture is actually
the outer coating of the mould from which the statue will be
made. On this statue, the left hand will be put on later. There is
no ritual reason for this- it's just easier to do it that way, instead
of trying to pour bronze through too many tricky little channels in the
mould.
3.
The mould is covered with heavy clay to stop it breaking up during pouring.
This is heated, and the wax melts and runs out a hole in the bottom (or
the top- the image is often cast upside down) to be collected and
re-used. Hence the name of the process- "lost wax". The nails that were
put through the wax hold the outer mould away from the core, and stop it
from collapsing as the bronze run through. The molten bronze is then poured
into the space between the core, over which the wax was shaped, and the
plaster mould. The plaster moulds nearby are for making smaller wax images-
they can be re-used. I couldn't work out what the old bicycle wheel was
for!
4.
When the bronze image is finally cast, and cools down, the plaster mould
on a larger image is cracked off. The image still needs a lot
of work- it might be engraved, trimmed, or polished. Sometimes there
are leftover chunks of bronze that need to be filed off. The holes
from the nails that kept the core separate from the plaster mould during
casting may be filled with the same bronze as was used for the image- so
you can hardly see them. If the bronze failed to reach any parts of the
image, patches may also now be added on and smoothed over.
© Bob Hudson, 1997-2003.