Tip #54: Firing Glass (in your ceramic
kiln)
Have you ever wondered about firing
glass in your kiln?
Kiln fired glass, or warm glass as it is also called, is typically done
in an electric kiln at temperatures lower than ceramic temperatures.
1300-1500 degrees F is typical. (For reference, Cone 04 is about 1900
degrees F and Cone 10 is about 2350.)
Because of the lower temperatures involved, all ceramic kilns are
capable of firing glass. However, electronic controllers are
particularly useful for glass firings, as the temperatures have to be
controlled precisely during certain stages of firing.
Glass kilns usually have an element in the lid. This is especially
important for glass fusing, where different pieces of glass are combined
into a single agglomeration by heating them to the point where they
soften, and a flow of material occurs across each piece. During fusing,
the lid element is turned on high so even heating occurs across the
glass piece.
If you're doing small pieces of glass,
a lid element is not crucial for fusing. If you're making jewelry
for example, the small tabletop kilns without lid elements work
fine. But the larger your pieces get, the more difficult it gets
to do without a lid element.
It also is extremely useful to see inside glass kilns, so windows are a great help.
Slumping (melting the glass into a
mold) does not need the element to be in the lid. So if all you're
doing is slumping, such as wine bottles or already fused sheets of
glass, any ceramic kiln will be fine.
Using a ceramic kiln for firing
glass
If you plan to do a fair amount of glass and ceramic work, then your
best option for a kiln would be a dual-media kiln which is designed for
both. These are the most popular.
Paragon
Janus Kilns
Olympic Dual Media Kilns
If you are a serious glass artist, you probably will want a separate
kiln for ceramic and glass. This will allow you to optimize features for
each one. Paragon is the most popular brand of glass kiln, and has a
variety of styles to choose from.
For more information
The website www.WarmGlass.com has
a lot of great information.
We also have a number of new books on kiln formed glass, including:
* Dictionary of Glass
* Glass, An Artists Medium
* Techniques of Kiln Formed Glass
A fun glass project
A fun project is to take a beer or wine bottle and slump it into a
"spoon rest".
Make sure you have a lot of kiln wash on your shelf. I personally would
try this first inside a ceramic bowl, just to be safe.
Make sure you have the bottle where you can see it through your spy
hole. Heat the kiln at about 250 degrees F per hour. The bottle will
probably start to slump at 1000-1100 degrees F, and be pretty flattened
by 1200 degrees F.
You can also add a lump of clay (dry greenware or bisque) beneath the
neck of the bottle, and it will form over the lump and make a nice
handle.
Cooling the kiln fast down to about 850 degrees F will probably result
in the clearest glass. Then cool very slowly
-------
Here is an image
of a bottle slumped into a serving tray. To give proper credit,
this nice looking item is sold at a web site called She-Works.com.
Item # G-901.
------------
Copyright 2002 Cindi Anderson
BigCeramicStore.com This tip was updated 6/28/10
Return
to main Tips Page
