Kiln Basics How NOT to burn your school down!
Do not open up or look into a kiln while firing. The peep holes are for cooling, looking directly at red hot anything will cause eye damage. You should wear dark glasses with UV protection when looking into a hot kiln. The worst thing you can do is fire low fire glazes or clay at high fire. The clay and/or glaze will melt all over your kiln and can cause major damage! If you have both low fire and high fire materials in your studio, you might want to mark your pieces differently on the bottom so you don't forget and get them mixed up! Some General Firing Tips
Manually turning the kiln on and up, and watching the cones inside the kiln through a peephole to determine when to turn the kiln off. Manually turning the kiln on and up, and using jr cones in a kiln sitter to turn off the kiln when it reaches temperature. Programming an electronic controller to turn the kiln on, up, and off when appropriate. There are 3 common ways to fire an electric kiln
Electronic Controller
Programming your Kiln Begin by pressing the STOP button.
Programming your Kiln Press the Cone Fire button Press Enter
Programming the Kiln The display will ask for a PreHeat time. Skip this by pressing ENTER The preheat setting helps drive water out of the clay, but it wears out your control panel and elements
Programming the Kiln The display will ask for speed.
Programming your Kiln For bisque ware always fire in SLOW mode. Press Enter
Programming your Kiln For glaze ware, fire using MED mode. Press Enter
Programming your Kiln Only bad things happen when you use FAST mode.
Programming your Kiln The display will then ask you the cone. This must match the clay cone. The clay cone will be stamped on the box of clay.
Programming the Kiln Low fire cone must begin with a 0, typically 04, 05, 06 Press Enter
What happens when you forget to hit the 0 in 06 Cone 06 = 1830 Cone 6 = 2232 That does not come off!!!
Programming your Kiln Finally it will ask for a hold time. Alway hold for :05 or 5 minutes to even out heat at the hottest temp. Press ENTER
Programming your Kiln Wait 30 seconds, the controller will flash IDLE
Programming your Kiln Hit the start Button
Don t forget to switch on your fan Always click the switch on before turning on the kiln. This will turn on the ventilation It removes fumes Improves firing consistency
Kiln Sitter
A junior cone of the appropriate number is set inside the kiln sitter box. The cone is held by a moving rod and a retaining bar. When the cone bends (because it has absorbed the correct amount of heat), the rod falls. The rod activates the control mechanism which turns off the current to the coils. How the Sitter works
Setting the Sitter Set the timer A typical firing is 16-18 hours. The timer is the backup. The kiln will stop when the cone melts.
Setting the Sitter Lift the center rod, it should move easily. Place a new pyrometric cone between the two lower bars and the top rod.
Setting the Sitter While you are placing the cone, lift the toggle.
Setting the Sitter The center rod on kiln interior is connected to the toggle release. You can not press the button if the toggle switch is up.
Setting the Sitter Press the button
Setting the Sitter When the kiln has hit the max temperature the cone melts, the toggle drops and the kiln shuts off.
Setting the Sitter When the kiln has hit the max temperature the cone melts, the toggle drops and the kiln shuts off.
Loading the Kiln
Loading the Kiln Never load wet pieces. If it is cold, it is wet. Kiln shelver should have been coated with kiln wash. Glazed projects should be on stilts. Maintain proper clearance. Pieces and shelves should be 1 inch from sides and 2 inches from top. Spread the work uniformly throughout the kiln. If using half shelves leave a gap between the shelves.
Bisqueware from above Fill that kiln up! It takes a lot of energy to fire it up, but be careful with fragile pieces. Bisqueware may touch. You may stack pieces on top of each other.
Glaze firing from above If possible, place the glazed work on stilts. Evenly space them apart by one inch, two inches from the wall. Don t stack them! Be sure you have applied a generous amount of kiln wash to your shelves.
Be sure your students don t overdo it with the glaze
Your shelves or your students work?
Kiln wash is vital! Protect your shelves with kiln wash. It s a powder that is mixed with water and brushed on the top half of the shelves. Once it starts to flake off, it may be scraped off and reapplied.
Unloading the Kiln Wait until the kiln reaches room temperature The bottom of the kiln is always significantly hotter
Cone chart and reading the cones
Neil Estrick (847) 223-1807 Kiln Repair & Maintenance
Great Lakes Clay http://www.greatclay.com/merchant2/merchant.mvc Telephone 800-258-8796 FAX 224-856-5419 Clay Supply company