Kiln Firing Directions to Prevent Kiln Explosions For firing a manual kiln - one with cones and a kiln sitter.

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1 Kiln Firing Directions to Prevent Kiln Explosions For firing a manual kiln - one with cones and a kiln sitter. 1.Put a cone in the sitter - I use cone 04 or cone 05 for bisque firings 2.Load the kiln 3.Prop the lid of the kiln open - use a kiln post if you do not have a lid support. 4.Set the limit timer to the maximum amount of hours 5.Turn one switch at the bottom on 6.Push the plunger button in the middle of the kiln sitter in to turn on the kiln 7.If you have a kiln vent attached to your kiln, turn it on 8.I like to fire the kiln with the lid propped open and one kiln switch on overnight when I am not there. This is key. The long warmup allows water to precipitate out of the clay without forming steam. Steam is the enemy - if steam forms inside of the clay pieces it causes them to explode. 9. When you arrive at school the next morning, lower the lid, add more hours to the limit timer and turn on the second switch. Then turn on one switch an hour until the kiln shuts off. The kiln should be done sometime in the afternoon. If the kiln does not shut off because the cone drops by the end of your teaching day, turn the limit timer to zero to shut the kiln off before you leave for the day. 10.IF YOU ARE NOT ALLOWED TO FIRE YOUR KILN OVERNIGHT - (I never ask if I can fire the kiln overnight, I just do it because the answer to most questions in schools is no.) What I do in this situation is prop the lid open, set the limit timer to the max hours and turn one switch on in the morning. Fire the kiln for an entire day like this with only one switch on. Shut the kiln off at the end of the first day. Then the next day when you come in, lower the lid and fire the kiln by flipping one switch on per hour. Because all of the water in the clay will have evaporated out the previous day you can fire the work on the second day like this without blowing it up.

2 Kiln Firing Directions to Prevent Kiln Explosions For firing a kiln with a computer controller. The easy one-push buttons on computer controlled kilns with names like slow bisque may not fire the kiln slowly enough for really thick work in a bisque firing. That is why I highly recommend learning to create your own firing profile for your kiln. This way you are in total control of how quickly or slowly the kiln fires the work. My kiln uses a Rampmaster II kiln computer controller. Below are terms that show up on the display when I am programming it. These terms will not be the same for all kilns, but the general principles will be the same. USER - My kiln can hold 5 different firing profiles (think of them as schedules) in the kiln. When I fire a bisque kiln, I need to recall USER 1. I have profile 2 set up as my glaze firing schedule. When the word USER appears on the LED screen on my kiln I choose the number of the profile/ schedule that I wish to use. SEG - This term stands for segments. I use the keyboard to select how many segments I would like my firing to have. Each segment contains the rate for how quickly the kiln is fired, what temperature that segment is going to reach and lastly a hold. A hold is selected if you want to hold the kiln at the temperature of the segment for a set amount of time. So basically you program a segment for how fast you want your kiln to reach a set temperature and then decide whether or not you want the kiln to hold at that temperature. Ra - This term stands for rate or ramp. It is the rate per hour at which the temperature in the kiln climbs. If you choose to fire your kiln at 100 per hour, over the course of the next hour the temperature in the kiln will increase by 100.

3 F - This term on the display stands for degrees Fahrenheit. When you enter a number into the keypad you are programming the computer to reach this temperature during this segment of the profile. HLD - This term stands for Hold. When you enter a number in this part of the profile you are programming the computer to hold the kiln at that segmentʼs temperature for set number of minutes or hours. If you program zero in at this prompt the kiln simply moves onto the next segment in the kiln firing profile after it reaches the temperature set in the current segment. This is what my kiln firing profile looks like when written out in words... USER 1 - This is the number of the bisque firing profile in my kiln. Different programs can be stored as different user numbers 2-5. Segments 3 - This is the number of segments that will be programmed into the kiln The first SEGMENT will fire at a rate of 75 F per hour up to 170 Then the kiln will HOLD at this temperature for anywhere between 1-8 hours depending on how thick the work is that I am firing. The second SEGMENT will fire at a rate of 100 per hour up to 600. There will not be a HOLD so the kiln will advance automatically to the third segment of the firing. The third SEGMENT will fire the kiln at a rate of 200 per hour up to There is no HOLD in this segment so the kiln will shut off automatically when it reaches All of this may sound confusing so here is my sample bisque firing profile for really thick work with notes describing why I chose the values I set.

4 What the kiln displays What I enter on the key pad Notes USER 1 My bisque firing profile is saved as USER 1 in my kiln. Other firing profiles are saved under different user numbers 2-5. Seg 3 This is the number of segments or parts in the kiln firing profile. This profile fires the kiln at three different rates of temperature increase. Ra 75 I want the kiln to increase in temperature at 75 per hour F 170 This is the temperature that I want the kiln to reach in the first segment of the firing. HLD 8 If I am firing really thick animal sculptures I want the kiln to hold at 170 for 8 hours to let all of the water evaporate slowly out of the clay. If I am firing thinner works, I choose either 4 hours or 2 hours based on my experiences firing kilns Ra 100 This is the start of the second segment of the kiln firing profile. I want the kiln to increase in temperature at 100 per hour. F 600 I want the kiln to reach 600 degrees in this part of the firing profile. I choose to fire slowly from degrees. HLD 0 I do not wish to hold the kiln at 600 degrees so by entering zero I am programming the kiln to move onto the next segment of the profile.

5 What the kiln displays What I enter on the key pad Notes Ra 200 Now that the work in the kiln is safely at 600 degrees I can increase the rate per hour that the kiln is firing at. When I enter 200 I am programming the kiln to increase in temperature by 200 per hour. F 1850 This is the last segment of the profile, so this is the final temperature that the kiln will reach. Choosing a number between is a safe bet for bisque firings. If your glaze work develops bubbles when it fires in the glaze firing, choose a number closer to HLD 0 I do not wish to hold the kiln at 1800 at the end of the firing so I input zero here. ALAr 9999 This is an alarm feature that the kiln has. I just press enter and leave it at its default setting of CPL There is nothing to enter in the keypad as CPL stands for completed programming.

6 Kiln Firing Directions for a Glaze Firing For glaze firing in a kiln with a computer controller. This is a firing profile that I would use if I was firing low-fire commercial glazes to cone 06 - the kind you buy in the little bottles. What the kiln displays What I enter on the key pad Notes USER 2 This will be a different firing schedule than the bisque firing schedule so it gets a different number in the computerʼs memory - in this case a 2. Seg 1 This is a simple firing profile so it needs only 1 segment. Ra 200 Because the work has already been bisque fired there is no need to go super slow at the beginning of the firing. Because of this the kiln can be fired at 200 per hour. F 1850 This is the final temperature that the kiln will fire to. If your glazes seem underfired you can increase this number. If they seem overfired, you can decrease this number. ALAr 9999 This is an alarm feature that the kiln has. I just press enter and leave it at its default setting of CPL There is nothing to enter in the keypad as CPL stands for completed programming.