Soda Firing 9-26-24

The 14th Kiln Firing is just about here. Follow along with the firing as I update this page on the hour.
Cones in our cone packs 012, 010, 06, 1, 4, 5, 6, 7

We will make the bag wall one brick higher this time around (again).

Kiln Log:

Temps are for the Top pyrometer the Kiln.

Details from the firing will be logged here each hour. The link to this firing will be posted on Clay Q&A.
We fit almost everything! I this firing we put in 4# of soda in 2 Gal of water.

The kiln was more even over all. For next firing we will be moved the target bricks backwards a few inches toward the burner inlets. Also in the October firing I will be reducing more during soda application aiming at more carbon trapping at the end of the firing. This may result in some more grey on surfaces and glazes with copper being reduced in some areas of the kiln.

7:00pm - 65ºF, Lit south burner, air on lowest setting. Gas low enough it does not read on the dial.

8:00pm - Top 377ºF/ Bottom 102ºF
It is blustery and raining. I am unsure if we will fire the north burner overnight as the gusts and rain come more from that side. We are holding the burner where it is at. Candling with a blue flame. Gas not reading above the first dash on the gauge. Damper at 2”

8:30pm - Top 447ºF/ Bottom 132ºF, gas to #0.5 south burner.
Air on LOW. Everything else holding at the same level.

9:00pm - 706ºF/202ºF, South burner at #0.5. Lit North burner candling! Exciting!

9:30pm - 868ºF/405ºF, South burner up to #1/ Air Medum or 90º. North burner #0.5#/ Air halfway between medium and low.
Opened damper to 3”.

10:00pm - 960ºF/558ºF, Both burners at #1, Air Medium. Damper at 3” open.

10:30pm - 1078ºF/736ºF, damper into 1.5”

11:00pm - everything stays the same, except the air was turned a hair up.

3:00am - 1430ºF/1328ºF, (hotter at this point than other firings). Bumped gas up to #2.
This is a big shift in firing style from other firings.

7:00am - 1853ºF/1825ºF, Body reduction happened overnight, thankfully it was reducing, so we did not miss it. Kismet! Gas bumped up to #3, Damper at 3.25”, Air on High. We are cruising.. This is the hottest temp achieved overnight! We will likely add soda in 3-4 hours, so between 11am-12pm.

8:00am - 1965ºF/1958ºF, The kiln is evening out and slowing down a bit. We opened the damper to about 4”. Gas is still on #3 and air on high.

9:00am - 2050ºF/2051ºF, The kiln is quite even now. Cone 1 is down top and bottom. The kiln climbed about 90º over the hour. That is a little faster than last firing which was 70º at this time. Overall it is slowing in rate of temperature increase and that is normal at the end of the firing. We will be watching the rate of increase to determine soda introduction. Guessing between 11:30am-12:30pm.

10:00am - 2106ºF/2114ºF, Still Cruising! Cone 4 is down top and bottom. C/5 is getting soft. It is likely we will be adding soda sooner than later. We climbed 56º this hour. If we climb around that rate, we will likely soda at 11:30. I am pulling the damper a touch to give it just a little more air, so it may climb at a slightly higher rate… maybe 60º an hour. If that happens we will more likely soda just before 11:30am or even at 11:00am. We shall see!

11:00am - 2167ºF/2175ºF, Slowing. cones bending. % is down on top, 6 is down on bottom. Right/ Left front side peep 6 is down, back side-peeps 6 is still up.

11:30am - 2186ºF/2194ºF, Cone six and seven bending top, Cone six down bottom. The side cones in the back are still vertical. Next firing we will move the target brick back toward the burners to try and get the back hotter/ push the flame upward sooner in its path. With a taller bagwall addition this firing, it makes sense that this could create more evenness. I think we will soda in 15 minutes or so.

12noon Started Soda - 2204ºF/2213. Seven-second counts with around five rounds. Each round dropped between 20-30 degrees. We waited to do another round until the kiln got back up to 2200 each round. A total of 4 pounds of soda in 2 Gal of water. All of the solution went in.

12:40 finished soda introduction finished. Shut of at 12:50pm

Graph charts the TOP temperature in the soda kiln.