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Pigeon Point
Lighthouse
The art of fused
glass that has become very popular today started 4000 years ago when the
Egyptian chemists made fused and slumped glass to please the pharaohs.
The artists now
are able to choose from many wonderful colors and forms of glass that have the
same coefficient of expansion or COE. Having the same COE
allows all of the glasses used together to expand and contract at the same
predictable rate. Some of the forms of glass are frits
(crushed glass), stringers (long thin strings of glass), confetti ( thin shards
of colored glass), noodles (thicker than stringers) and powdered glass. These glasses have been extensively
tested to be compatible by the glass manufacturers. This partially explains
why fusible glass is more costly than stained glass. If
the glasses used are not compatible the glass will become unstable and crack or
shatter.
One other very
interesting form of glass is the dichroic glass that was developed because of
the space program and passed along to artists. Dichroic glass is created by
applying metal oxides in a high temperature vacuum furnace to either a black or
clear glass base. The process the dichroic glass goes through is reflected in
the costly price. A piece of dichroic glass when turned at different angles
will appear to be a different color. Actually it has two colors that transmit
and reflect different colors when viewed at different angles.
Glass is cut to complete the desired design and this can be simple or
complicated sometimes incorporating glue to hold pieces in place. An example of
a completed design may have a colored glass on the bottom with several forms of
glass or metal inclusions in the next layer and covered by a clear layer of
glass. The number of glass layers and type of glass will effect the time and processes it will go
through in the kiln. Tiny Champagne bubbles are a natural occurrence when
two or more layers of glass are fused together as the edges seal first. The glass can
also be sprayed with chemicals that will produce
more bubbles than naturally occur in the fusing process depending on the
artist’s desired effect.
I do not use
chemicals to induce bubbles; however I do use a few techniques to induce more of
them in my underwater scenes.
Using metal inclusions will create more bubbles; some are difficult if not
impossible to remove.
The completed piece is then placed in a room-temperature kiln. It is heated to
the desired temperature, usually around 1500 degrees. The glass may have several
stages to go through to get to the
desired temperature depending on what the artist wants to accomplish.
The first stage is from room temperature where the glass is at a rigid stage to
the next stage where the glass is heated and moves through a more flowing form.
If heated too quickly the glass will crack and break. By the time the
temperature of the glass gets above 1000 degrees any glue or moisture will have
burned off and the glass begins to soften and will look
slightly glossy.
When the glass reaches around 1300 to 1400 degrees the glass will appear to glow
in an orange-red color. The edges will soften and start to become round. The
layers of glass will start to stick together. This is also the slumping range
(between 1250 and 1350 degrees). If slumping is the goal, then the next stages
would be to anneal and cool.
As the heat
rises to 1500 degrees the glass becomes
increasingly more liquid and begins to glow a bright red. Bubbles start to move
toward the surface of the glass and pop. (Some artists apply chemicals in the
design stage to help create the bubble effect.)
After the glass has been soaked (held) to reach the desired effect the kiln is rapidly cooled.
The main reason to cool rapidly is to reduce the amount of time glass spends
above 1300 degrees. Glass left too long at this temperature range will devitrify.
Devitrification is where the chemicals rise to the surface giving the finished
glass a cloudy or “sea glass” effect. Some artists do this intentionally to create that look in
their pieces.
Once the rapid cooling phase is complete and color has started to return to the
glass, the kiln has to be cooled to approximately 1050 degrees and the
“annealing” phase begins. Annealing is a process where the stress in the glass
is relieved
and the molecules in the glass are allowed to cool and arrange themselves into a
solid and more stable form. There are three stages to this annealing point that
the glass has to pass through which includes
soaking or holding at various points before it goes down to the next
temperature. This is crucial to creating glasswork that will remain stable once
it cools to room temperature. My kiln takes about 12 to 14 hours to cool down to
room temperature at which time the piece can be safely removed from the kiln.
The piece can then be placed in a manufactured or handmade mold and will go
through a slumping fire to produce the desired shape and will cool down in the kiln for about
12 to 14 hours to room temperature.
After sculpting for many years, I was introduced to glass fusing while taking a
refresher sculpture course at the College of San Mateo. I continued glass fusing
at the college for a few years. I then attended glass
fusing and carving classes and seminars in Northern and Southern California and
in Oregon.
Some of my artwork can also be functional. The glass I use is lead-free,
and should be treated like a treasured piece that does not get put into the
dishwasher.
The mystery of the glass process and the delight I get when I open the kiln to
see the results have kept me fascinated and passionate with creating art through
the glass fusing processes. The amazement I feel when I observe artwork being
created before my eyes as I carve into glass, fused and mirrored, is sheer
delight. I hope you will enjoy my artwork as much as I enjoy
creating it for you.
Melissa
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