In a nutshell, this is how we
make sculpture and fine jewelry. The "lost wax"
casting process, goes something like this:
From a model sculpted of clay,
metal or wax, Malcolm creates a mold for
reproduction. Molten wax is injected into the
mold and allowed to cool, leaving a wax pattern,
which is checked for detail and completeness.
The wax pattern is "tree'ed
up," or attached to a base using additional wax
for hold and support. A stainless steel flask
(like an open tin can, or tube) is placed around
the wax parts.
We mix and pour "investment"
(plaster, with material suited to take extreme
heat) over the wax parts in the flask. The
contents are then vacuumed in a chamber to
release the air bubbles. Once set, the flask
base is removed, leaving only the investment,
and the wax patterns suspended in the
investment, inside the flask.
After drying the investment for
2-4 hours, we slowly "burn out" the flask in an
oven overnight, at temperatures reaching 1300
degrees F, eliminating the remaining wax. With
the flask temperature reduced to 900 plus
degrees F for casting, Bronze, Silver or Gold
metal is melted in a crucible. At just the right
moment, the metal is cast into the flask,
filling the space left from the burned out wax
After the metal casting is
broken out of the flask using a waterjet tool,
the cast parts are cutoff from the metal tree,
sandblasted, and prepared for finishing.
Next is "deburring," or
grinding and sanding, followed by polishing, or
when flat surfaces are involved, "lapping."
Plating of Gold or other metals
follows if the job requires, then final
assembly, setting of stones, mounting to base,
Easy as 1, 2, 3....4, 5, 6, 7,
8, 9, 10, 11, 12.