Kiln cast glass sculpture
(Please click pictures to see enlargements)
3. After the plaster hardens I remove the clay from the molds. At this point the clay original has been destroyed so that if anything goes wrong with the mold I must start over.
4. Once the plaster molds dry I place them in an electric kiln and fill them with pieces of glass. This is when I can choose which colors of glass to use. I can control the coloring of the sculpture by placing different colored pieces of glass in different areas of the mold. Once the mold is filled with glass I start a firing cycle that rises the temperature up slowly over several days.
5. When the temperature reaches the melting point of the glass, around 1500 F degrees, I will usually have to add more glass to the mold to keep it full.
6. Since all of the glass melting takes place inside a kiln this technique has become known as kiln casting rather than hot casting, where glass melted in a furnace is poured into molds.
the glass has completely melted and the
molds are full I start a cooling or
annealing cycle. Glass must be cooled slowly
from its melting point down to room
temperature or it will develop stress that
can cause cracks. When the kiln has
completely cooled down, usually after one
week, I can take the molds out and break
them apart to remove the solid castings. If
anything goes wrong with the castings at
this point I will have to start over with
working in clay as the molds are destroyed
while removing the glass. I may make a
series of sculptures that are similar but no
two pieces are ever exactly the same. Each
sculpture I make is a true original. I have
to finish the castings after I remove the
plaster molds. I use a diamond saw, belt
sander and sandblaster to smooth rough edges
and fit separate pieces together. The
surfaces of the sculptures are the result of
the texture that was in the plaster mold.
Since most of my sculptures are made of more
than one piece I use Hxtal, a special epoxy
glue which is made for glass to bond the
pieces together. This epoxy bond is stronger
than the glass itself and will not
deteriorate in ultra violet light.