Automatic kilns and even manual kilns shut off by the use of cones are never as accurate as the human eye. 99.999% of the time this is fine. However, for the rare artist who needs the utmost precision, here is another method.
- Set your kiln control to fire about 25 to 50 degrees higher than you need to to achieve proper maturation of your witness cones.
- Know when your kiln will reach the approximate temperature that you want to achieve. Set the Alarm to start buzzing at a lower temperature (like 50 to 100 degrees below where the cones will mature. The Alarm is not very loud so be aware of that.
- Watch the witness cone through the peephole (or better yet several witness cones through several peepholes).
- Shut off the kiln power with the toggle switch as soon as the witness cone bends to the proper degree.
Note: This is essentially what potters did before they had automatic controls.
