Download and print a firing schedule for a manual kiln without a commercial downdraft vent or with a commercial downdraft vent

Firing Schedule BASICS

All kilns are different, and every firing is different, depending on density of load, weather conditions, kiln and element conditions, and many other factors.  This firing schedule is intended to be used as a guide and should be adjusted to your own unique firing situations.  Some people will find better results by staggering the times  the switches are turned up (i.e. at step 4 on the bisque firing, turn the second switch to low, then 30 minutes later, turn the third switch to low).  We recommend  when altering this, or any, firing schedule, you adjust one variable at a time so if something goes wrong, the problem is easily identifiable.  We also recommend keeping a firing log and the fired  cones as a record of your firings.  Regular preventative maintenance is also suggested.  Checking the kiln sitter with a firing gauge, vacuuming the firing chamber, kiln washing shelves, and checking how evenly the kiln is heating by placing witness cones on the shelves, should all be done on a regular basis.

 

FIRING SCHEDULE: FOR MANUAL ELECTRIC KILNS WITH A COMMERCIAL DOWNDRAFT VENT

The bisque firing

1) Place a junior cone 03 (“sitter” or “small” cone)  in the sitter as you load your kiln.

*Many people forget to put the cone in the sitter as they load the kiln, but once they do, they rarely forget ever again!

2) In the evening, set timer to maximum time, then turn on bottom switch ONLY to low.  This process may also be done over several hours before firing. The vent should be on, but it isn’t necessary at this point.

*This phase of “preheating” helps to slowly remove moisture from your pieces.  This is an extremely critical point of firing.  Water turning to steam expands 1,170 times, and if the water in the clay turns to steam too fast, the piece can blow up.  Even though your pot may feel totally dry, there is still moisture in the clay.

3) The next morning, reset the timer for 30 minutes – 1 hour longer than the firing time and turn all switches to low for 3 to 4 hours.  If you don’t already have the vent on, turn it on now.

4) Turn all switches to medium.  Leave at medium for 3 to 4 hours.

5) Turn all switches to high.  Given all variables, a good estimate of the remaining firing time at this point (from when you turn the kiln up to high to when the sitter shuts off the kiln)  is approximately 2 – 3 hours.  Vent stays on during the cooling process.

 

The glaze firing

1) Place the junior cone appropriate for your particular glaze firing in the sitter as you load the kiln.

*Again, people generally forget this step only once.  Preheating is not necessary in this stage.

2) Set timer for 30 minutes to 1 hour longer than the firing time and turn all switches to low.  Turn vent on.  Leave switches on low for 3 to 4 hours.

*Many people prefer to start a little slower by turning the bottom switch to low, then 30 minutes later turning the other switches to low.

3) Turn all switches to medium, leave at medium for 3 to 4 hours.

  1. Turn all switches to high.  Given all variables, a good estimate on firing time from when you turn the kiln up to high to when it shuts off is approximately 3 hours for a low-fire glaze firing.  Higher cone firings will increase the firing time by an average of 15-30 minutes per cone number. Vent stays on during the cooling process.

FIRING SCHEDULE: FOR MANUAL ELECTRIC KILNS WITHOUT A COMMERCIAL DOWNDRAFT VENT

The bisque firing

1) Place a junior cone 03 (“sitter” or “small” cone)  in the sitter as you load your kiln.

*Many people forget to put the cone in the sitter as they load the kiln, but once they do, they rarely forget ever again!

2) In the evening, set timer to maximum time, then turn on bottom switch ONLY to low.  This process may also be done over several hours before firing.  Peephole plugs should be out, and the lid should be propped open.

*This phase of “preheating” helps to slowly remove moisture from your pieces.  This is an extremely critical point of firing.  Water turning to steam expands 1,170 times, and if the water  in the clay turns to steam too fast, the piece can blow up.  Even though your pot may feel totally dry, there is still moisture in the clay.

3) The next morning, reset timer for 30 minutes – 1 hour longer than firing time and turn all switches to low for 3 to 4 hours.  Leave the peephole plugs out and the lid propped until you turn the switches to medium.

4) Turn all switches to medium, leave at medium for 3 to 4 hours.

5) Turn all switches to high.  Given all variables, a good estimate on firing time at this point (from when you turn the kiln up to high to when the sitter shuts off the kiln) is approximately 2 – 3 hours.

The glaze firing

1) Place the junior cone appropriate for your particular glaze firing in the sitter as you load the kiln.

*Again, people generally forget this step only once.  Preheating is not necessary in this stage.

2) Set timer for 30 minutes to 1 hour longer than firing time and turn all switches to low.  Peephole plugs should be out, and the lid should be propped open.  Leave switches on low for 3 to 4 hours.

3) Put peephole plugs in and close lid.  Turn all switches to medium, leave at medium for 3 to 4 hours.

4) Turn all switches to high.  Given all variables, a good estimate on firing time from when you turn the kiln up to high to when it shuts off is approximately 3 hours for a low-fire glaze firing.  Higher cone firings will increase the firing time by an average of 15-30 minutes per cone number.