Firing - Kiln

The Jewelry and Metal Craft Shop currently has one small programmable kiln. It is a model J-100 from Satellite Manufacturing Co. Tinkermill modified it to add a programmable controller similar to the Advanced Temperature Controller, Ramp and Soak Controller. See Media:PID-RS.pdf for operation.

Control Profiles

What follows documents the heat profiles that have been programmed and the basic programming steps. Temperature settings are in Centigrade unless otherwise noted. (Accurate as of Dec. 22, 2016)

• STEP 1: Plug directly into wall outlet capable of handling 120V @ 14A as spec'd.
• STEP 2: Turn round knob to Hi (On) Check the mode ("M" Manual or "A" Automatic)
• STEP 2.5 If controller is set to M (Manual) mode, switch to A (Automatic) mode by pressing A/M key.
• STEP 3: From Manual mode, press and hold the STOP button for 2 seconds to stop any running process and reset the controller. (If a program was running when power was shut off, it can resume automatically when powered back up.)

Display: Left side shows current temperature in degrees C. Right side flashes between "stop" and a number indicating the first set point temperature in deg. C.

• STEP NEXT: depends on profile desired. See below.

Profile: Burn Out

This is part of the process of Lost Wax Casting that burns out a wax model from an invested flask.

STEP 4: Hold down the RUN/HOLD button for about 2 seconds. -- Right display will change to "run" and then switch to the % on-time of the heater to accommodate the program. Preceding the % on-time number is either an "A" or an "M". It should be "A" for Automatic mode. If it is not, press the A/M button. It will switch it to "A".

The program does the following automatically:

Start at room temperature (20C/68F)

Ramp up for 5 minutes up to 204C/400F

Soak for 60 minutes at 204C/400F

Ramp up for 15 minutes to 538C/1000F

Soak for 4 hours at 538C/1000F

End program. Cool naturally in kiln or crash cool by opening door.

Profile: Glass Annealing/Tempering

• STEP 4: Press the SET key briefly twice. The current Step number will display.
• STEP 5: Press the arrow UP key /\ briefly to increment the Step number or the arrow DOWN key \/ to decrement to Step number 10 which is the first step of this profile.
• STEP 6: Press the RUN/HOLD key and hold 2 seconds until the right display shows "run" momentarily. The display will switch to show the current measured temperature and the Set Point (the target temperature)

The program does the following automatically:

Start from room temperature (20C/68F)

Ramp up for 15 minutes to 538C/1000F and hold there - display shows "hold"

Holds indefinitely at that temperature awaiting command to continue (Allows Nancy time to load the kiln and resume program)

• STEP 7: Press the RUN/HOLD key for 2 seconds to resume the program execution. Display changes to "run"

Ramp temperature down to room temperature (20C/68F) over a 5 hour period (= 93C/200F/hour)

End program.

Useful Key Operations:

When program is running, press SET key twice to see the current step running. Press a third time to see the minutes elapsed in that step. Press a 4th time to go back to normal display.

To stop the program at any time manually, press and hold the STOP key for 2 seconds until "stop" displays. Current Step is reset to Step 1 but not executing.

To pause the program (hold) at any time manually, press and hold the RUN/HOLD key. To resume press and hold that key again until "run" displays.

To make the program begin at a desired Step manually, press the SET key twice to show the current step being executed. Press the arrow UP key /\ to increment the Step number or the arrow DOWN key \/ to decrement it to the desired Step number.

Resources

Media:PID-RS.pdf:  User Manual for programmable controller
Media:The_Ultimate_Silver_Metal_Clay_Firing_Guide_-_Cool_Tools.pdf: Firing Guide for Silver Metal Clay
Media:Firing_Precious_Metal_Clay_and_Art_Clay_Silver_is_easy.pdf : from SilverClay.com