search  current discussion  categories  kilns & firing - misc 

electric kiln wall thickness ...

updated sun 6 jan 02


Craig Martell on fri 4 jan 02

Jose asked:
> So, is it possible to upgrade a kiln designed for a cone 7 to a cone 10,
> by simply adding the required insulation?

Hello Jose:
Sure, you can fire a kiln hotter if you add some extra insulation. I've
fired electrics rated at cone 8 to cone 10 just as they were.

Most manufacturers use Insulating Firebrick rated at 2300 F. This is what
most of us use for a cone 10 reduction kiln too. The big difference is
wall thickness and heat retention. My gas kilns have walls that are 9
inches thick. Most electrics available have 2.5 and 3 inch walls. The
other thing is element wire guages. If you are going to fire to cone 10
it's good to have elements made of 14 guage Kanthal. Lighter wire will
fail quicker and you'll have to change elements more ofter. You can have
elements made to your specifications.

regards, Craig Martell in Oregon