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Tibetan Art - Cast Stone
Tibetan Art - Bronze
Mayan/Aztec-style Art
Other Sculptures
What are Mantras?
Metal Casting
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How the Sculptures are Made
Most of the bronze sculptures on this site are made using the "lost
wax" method a complex, multi-stepped process that can be broken down
into 15 different steps as indicated below:
1. Make a model in clay or another material. Clay is preferred
as the rubber mold applied in the next step will pull off of clay most
easily. Other materials will likely require a coat of releasing agent.
2. Create a mold from the original clay sculpture. Specially made compounds
can be used for this step or one can use sealing silicone commonly available
in hardware stores. A plaster "boot" is necessary for most
pieces so that when the original clay sculpture is removed from the
mold the mold will retain its shape.
3. Wax is poured into the rubber mold, often in three stages in order
to build up thickness. The cooled wax is then carefully removed from
the mold.
4. Since there are almost always a few holes or seams in the resulting
wax positive the next step is to "chase", or repair, the wax
using a variety of sculpting tools.
5. The wax positive is gated with wax tubes, providing channels for
the wax to be melted out, and funnels called sprues are attached to
channel the molten bronze into the piece. The piece is also vented with
wax tubes to avoid air entrapment.
6. The sprued and gated wax is dipped in a clay slurry then, while it
is still wet with the slurry, it is coated with varying grades of sand
from fine to coarse. Between coats of sand it is allowed to completely
dry. Depending on the dimensions of the piece from six to ten coats
will need to be built up. In the end the resulting ceramic shell will
be from 1/2 to 1 inch thick.
7. Usually it will be necessary to drill holes in in the ceramic shell
so that when the piece is heated in the next step the natural expansion
of the wax won't crack the shell.
8. The ceramic shell is inverted and heated. This causes the wax to
melt out, and so become "lost". The negative space in the
shell will become the positive bronze casting. The holes made in the
shell in step 7 are then plugged so that the bronze poured in during
the next step won't simply flow out as it is poured in.
9. Bronze ingots are melted to a temperature of 2100 degrees. The molten
bronze is poured into the shell.
10. After the bronze cools enough that it won't run out of the shell
the shells with the still very hot bronze are immersed in water to speed
up the cooling process and prevent the bronze from shrinking anymore
than it has to.
11. The shell is broken away leaving the bronze where wax once was.The
gates and vents are sawn off, and the surface is repaired--usually there
are a few flaws and bubbles left from the casting process.
12. If the bronze is complex the different pieces will then be welded
together to reform the complete piece. The weld lines need be chased
so that the texture matches the area of the surrounding surface. 
13. The entire sculpture needs to be sandblasted at this point so that
the surface will hold a patina.
14. Different patinas can now be applied. A variety of chemicals and
paints are used to achieve the desired finish.
15. Finally the patinaed surface is coated with paste wax to protect
the finish, and the finished sculpture is fixed to a base if needed
or desired.
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