Cow dung is placed on top of the mold and below the mold.
The cow dung is then lighted. A fire is made with the mold in the
center. The entire mold is effectively heated so that the wax can melt
out of the piece forming a river of wax which collects in the pool.
Thus the mold has effectively lost its wax, hence the name “the lost wax
method”. The result is a near perfect replica of empty space of
the wax mold within the earthen mold.
The clay that was placed on the ground to form a channel was
placed there so that the wax would not mix with the dirt. Thus the river of
wax can be extracted from the clay and used again for future wax molds. 10%
of the wax cannot be recovered because it is burned away.
T
he
heat of the fire is not hot enough to melt all the wax form within the mold.
The excess wax is removed in the next
stage of casting the mold.
The approximate amount of time the fire is kept lit from
start to finish is:
1 hour for a 12 inch wax mold
2 hours for a 24 inch wax mold
2 hours for a 36 inch wax mold
4 hours for a 48 inch wax mold
6 hours for a 60 inch wax mold
8 hours for a 72 inch wax mold
