Stuart Gair Workshop Firing

This will be our 36th Kiln Firing. (But the very first of this style!!!)
Follow along as I update this page on the hour.

Cones in our cone packs 012, 010, 04, 1, // 4, 5, 6, 7, 8

Kiln Log:

Candling Burner Flame @ 10pm

I will log the temperature, gas, damper, and notes about the firing here.
✔️ General schedule - body reduction late morning
🥗 Potluck, 5pm: Finger food to share
🔥 Soda introduction, glaze reduction, oxidation cool 5-10 pm

  • 6:00pm - 69ºF Top, 70ºF Bottom KILN START TIME
    Both pilots lit. I am lighting the burner intermittently (and then turning it off) to hold the kiln just below 200ºF to help dry the wadding. Fans on low. Damper at 2”

  • 8:00pm - 214ºF Top, 137ºF, Lit North Burner. Candling (not reading on gas gauge). Damper at 2”

  • 9:00pm - 359ºF Top, 147ºF, Lit South Burner. Candling. Adjusted Rheostats so the lowest low was even softer. Nice, gentle. Candling blower speed. Damper at 3”

  • 10:00pm - 567ºF Top, 299ºF, Tiny gas bump on each burner.

  • 11:00pm - 841ºF Top, 492ºF, Gas bump on each burner = 0.25WC, Damper at 2”, Air low

  • 2:00am - 1352ºF Top, 980ºF, No changes

  • 4:00am - 1479ºF Top, 1171ºF, No changes

  • 6:30am - 1619ºF Top, 1377ºF, Tapped in the damper about 1/4”
    012 is down on top! Definitely uneven, and this is usual for this kiln at this temperature.

  • 7:00am - 1620ºF Top, 1420ºF, Gas up to 0.5WC, Damper at 2.5”, Air Low-Med

  • 8:00am - 1683ºF Top, 1522ºF
    010 bending on top. Before it touches down, we will start body reduction and will be in this stage for 40-60 minutes. We started body reduction around 8:15am.
    At the beginning of body reduction, the kiln was at 1699ºF Top, 1547ºF
    We reduced the air, increased the gas at 1WC, and pushed the damper in about 1/4”
    The flame coming out of the top peep was about 6” long, dark orange-red, and smoky.
    Poofs of smoke were coming out of all the cracks.
    We made sure the flames were not back-burning into the burners.
    At the end of body reduction, the kiln was at 1664ºF Top, 1587ºF (evening the kiln out overall)

  • 9:00am - 1664ºF Top, 1587ºF (77º difference)
    To take the kiln out of body reduction, we opened the damper, increased the air, and increased the gas to get it into a climbing neutral/ light reduction. There is still a significant flame coming out of the top peep. Bright orange. No carbon at the tip. Burners are starting to sound like rockets.
    Reset kiln to have gas at 2WC, damper at 4.5”, air at medium.

  • 10:00am - 1834ºF Top, 1776ºF (58º difference)
    We are in a steady climb, and the bottom temp is slowly catching up with the top temp in this neutral/ light reduction. No changes to gas or anything else this hour. I estimate that cone 6 will be bending in 6 hours (around 4pm).

  • 11:00am - 1936ºF Top, 1891ºF (45º difference)
    We are cruising!!!
    No changes to gas or anything else this hour.

  • 12:00NOON - 2014ºF Top, 1987ºF (27º difference)
    Bumped up the gas at 11:30am as the kiln had slowed down. 2.5WC, damper still at 4.5”, Air Medium. I estimate that cone 6 will be bending in 2.75 hours (around 3).

  • 1:00pm - 2087ºF Top, 2069ºF (18º difference)
    2.5WC, damper still at 4.75”, Air Medium.
    I estimate that cone 6 will be bending in 1.5-2 hours (around 2:30-3:00).

  • 2:00pm - 2147ºF Top, 2136ºF (11º difference), 2.5WC, damper still at 4.75”, Air Medium.

  • 2:30pm - 2180ºF Top, 2170ºF - Peak Temperature
    Started Soda Introduction at 2:30 when the cone 6 on top was flat.
    6.5 pounds of soda in three gallons of water
    60 second sprays in 2 ports in medium reduction, followed by heavy reduction with
    3 WC gas/damper in 1/4”/wood slivers in burner ports= more reduction.
    Then we pulled a draw ring.
    This was repeated till the soda was used up.
    Temp drop overall -164

  • 3:15pm - 2016ºF Top, 1962ºF (11º difference), 2.5WC, damper still at 4.75”, Air Medium.

  • 4:00pm - finished soak (45 minute to an hour)

  • 4:08 - Oxidation Cool = all peeps on building side out (other side too tight next to tree). Damper open. Door open on easy access side. Hold till the color brightens down (no dull red). Close everything up. We left the top peeps in the door and south kiln wall open to help us unload in within the workshop time frame.

  • 6:00pm - 1713ºF Top, 1678ºF Bottom - Cooling

  • 10:00pm - 1388ºF Top, 1316ºF Bottom

  • 7:00am - 1014ºF Top, 945ºF

This is a general graph of the heat change over time.

Front Stack

Middle Stack

Back Stack