Do I need Top elements?
Top elements are not required for slumping glass.
Therefore, you can do slumping in any electric kiln.
Top elements are desirable in glass fusing, particularly when
you get to large pieces (larger than a plate for example). They
are not required for fusing jewelry and smaller pieces. In fact,
it is possible to fuse any glass without top elements, but much more
difficult to avoid cracking.
Do I need an Electronic Controller?
An electronic controller is essential in firing glass, to get the
temperatures exact and control the heating and cooling
rates.
Can I Fire Ceramics and Glass in the Same Kiln?
We get many questions from people who want to fire glass and ceramics
in the same kiln. Following are some of the
issues.
* Temperatures
Ceramics are fired at hotter temperatures than glass. So if you
want to do both, you need a kiln capable of ceramic temperatures
(2100-2300 degrees F). (Glass is typically fired at 1400-1600
degrees F.) Most glass kilns are not rated to ceramic
temperatures.
* Kiln Operation
Kiln functionality is optimized differently for glass fusing than for
ceramics. For glass fusing you want to be able to turn
the lid element on full blast during the critical part of the fusing
process. So you don't want the lid element tied into the
electronic controller. But for ceramic firing you probably would
want the lid element tied into the controller, unless you didn't need
its additional power to get to your ceramic firing
temperature.
* Technical Challenges
The complicated issue with top elements is that over time they will
sag. Different manufacturers solve this in different ways.
The Paragon glass kilns use a different type of element which does
not sag, but these elements cannot go above 2000F. So in terms of
ceramics, these kiln can only do low fire and china painting.
Since the "glass" kilns tend to be large and shallow, you
don't have much element surface area on the sides of the kilns compared
to the volume inside the kiln you are heating. So these are the
toughest kilns to get to ceramic temperatures, especially without using
the lid element.
Olympic will put a top element in any ceramic kiln for a small additional
charge. They cut channels with a lip to keep the elements from
sagging. It has a separate switch so you would just leave it off
during ceramic firing. This would be the best option for someone
who wants to fire ceramic and glass on a regular basis..