You can use a ceramic kiln for glass – but there are challenges.
Even heating is critical with glass – which is why glass kilns heat from the top. Ceramic kilns heat from the sides so the edges of your glass will get more heat than the center. The larger the glass, the more of a challenge this is.
The heating and cooling steps for glass are more complicated than ceramics. If the ceramic kiln doesn’t have a digital controller you are adding an additional layer of difficulty firing pieces. Again, the bigger the work, the harder it is to fire without a controller.
So – yes, you can do it – but it gets tougher as the work gets bigger.
Paul
FusedGlass.OrgHelios Kiln Glass StudioPaulTarlow.com