How does thermal mass affect my firing (create devitrification)?
The amount of stuff (ceramic and glass) that you have in the kiln, is called the thermal mass. The more thermal mass you have in the kiln, the more time (and energy) it will take to get up to temperature. This can become an issue not only for the pocketbook, but also for the devitrification of the glass if the rate of climb between 1300 to 1400 degrees Fahrenheit, is slower than 250 degrees Fahrenheit per hour. This also becomes more of a problem on the way down, if the rate of fall is not greater than 250 degrees per hour (more thermal mass, the longer it will take to fall through this range, especially if the kiln is not vented).
