My Kiln

Kiln

Kilns are like selecting a car with too many manufactures, sizes and options.  Many beginning potters start with a small kiln only to discover their production out grew the kiln size.  I started with a mid-sized kiln in hopes it would meet my production goals.  I chose a Skutt 822-3 based on the size and amps power used.   My wheel helped define the kiln width but amps used to fire also factored in.  Typically I use 4 shelves and fire 17 to 30 pieces.  The bottom of the kiln is reserved for green ware and the top shelf is used for plates and tiles.   A shelf can hold 7 to 8 mugs or 10 to 12 tea bowls.  I use smaller pieces to fit around large bowls and plates to insure a full kiln.  Consider making slightly taller and reduced diameter to increase the number of pieces per shelf.  For example my mugs are current thrown at 3x5 rather than 3.5x4.5 to allow 9 to 10 pieces per shelf.

The kiln electric kiln is under a covered deck outside.  It is not totally weather proof but covered with plywood when not in use.  There are enough sunny days to allow regular firing but requires some awareness of potential for bad weather.  The controller is covered with a spare kiln shelf using spare kiln stilts to offset from kiln top when fired during potential precipitation.  On average I fire every 5 days but when I am in throwing mode it can be every 3 days.  The typical firing cycle is 3 days (one day to heat up and two to cool). 

Ideas and Hacks

1. Add a dial thermometer with a 6" stem to the middle of the vent on top of the controller to monitor the temperature.  

2. Keep a log of firings (Date, Type, preheat time, Cone, Speed, Hold time, Duration, days between firing).

3. In winter conditions, preheat controller with a small space heater to +38 F degrees and continue to heat controller until kiln reaches 60 degrees F.  

4. In summer conditions of  +80 F, the controller is cooled with the space heater set to fan only.

5. Kiln settings are preheat (final drying at 180 degrees) = 58 minutes for bisque ware; cone =10; Ramp = med for Bisque ware and slow for glazed ware; and Hold = zero minutes.

6. Drip chips are used under all pieces.  Drip chips are made by rolling out a sheet of clay on canvas cloth and rolling rubber shelf liner pad to make rough upper surface.  Remove pad after final roll.  Cut into 1, 2 and 3 inch squares and press between two pieces of plaster board.  Let dry and bisque fire cone 10. Use rough side up.  The addition of drip chips to the firing process has reduced the need to grind or chisel glaze drips. 

7. Purchasing a new kiln shelf requires taking old shelf to get the correct size.  The 3 inch bricks of my kiln makes dimensions about an inch smaller.  Consider reordering the pack of shelves that were sold with the kiln rather than individual shelves.  

8. Kiln shelf wash is not very protective from glaze drips so use the drip chip.  

9. Use an angle grinder with a diamond disk to remove glaze drips.

10. Thermocouples are changed every 40 fires and elements every 120.  Better to change on a schedule then to have them burn out during a firing.   Check amps in diagnose menu of setup program on kiln when element are new and monitor as you use the kiln.  For my kiln the amps for the 3 relays adds to 33.4 amps.   The number of amps was found in dimension description table of sales information data sheet.  

11. Skutt service indicates you can use the time it takes to fired but I found it varies depending on start temperature and size and number of pieces.  I just use the number of times fired to determine when to change thermocouples and elements. 

12. The kiln relays were replaced May 19, 2022 because of an E-8 error.  E-8 error indicates kiln did not heat up to final temperature suggesting a bad element or relay.  After checking conductivity of elements I ordered relays.  The Skutt 822 requires 3 relays. 

13. The kiln produced an E d error suggesting the temperature was not rising fast enough on 11/25/2024.  When the temperature rise wa monitored it rose and fell before rising again.  Controller was removed and a 12 v battery was used to check the relay.  All relays worked.  Controller was reinstalled and preheated to 60 F using a heater.  Kiln ran and temperature came up to cone 10.  Looked normal so kiln allowed to cool overnight.   In the morning temperature read 535 F and looked normal.  That night kiln was showing FAILED and when cleared the temperature was 113 F.  Pressing the review button revealed the E-d error.  I have ordered 3 relays.