Disoriented
Sep. 14th, 2018 03:18 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
offcntrSo my firing got off to a great start this morning: orange heat in the kiln when I arrived at 6 am, the first cone, 08 (like negative 8) down on time by 7:05. I put the kiln into body reduction for half an hour, then adjust the damper and burners for the duration of the firing, checking the cones and pyrometer every half hour to see how things are progressing.
The pyrometer is all over the map, so I pull out the thermocouple and swap in the other one from the small gas kiln, assuming (correctly, once it cools) that age and corrosion have worn this one away. But the cones haven't begun dropping at the bottom peep hole.
At 9 am, cone 04 goes down on the top of the kiln. Still no movement on the bottom. By 10 am, cone 1 is showing signs of softness, I've fiddled with the damper twice, the burners three times, and if I'm not at my wit's end, I can see it from there. My next two shows, not to mention a bunch of special orders, are riding on the success of this firing.
I was in the bathroom when inspiration hit. I finished and flushed and scrambled for the kevlar gloves, pulled out the peep plug, and sure enough: I'd put the cone pack in backwards.
Cone packs, as we use them, contain eight cones, set in two rows of four. I use cones 08, 04, 1 and 4 in front, 8, 9, 10 and 11 in back. If I put the pack in back-to-front, that meant I was looking at the wrong cones. And in fact, cones 08 through 1 were all down back behind the front rank; the only cone standing was cone 4.
Which meant my firing was perfectly on track, and I stop could stressing and go back to mixing glazes, making tests and mopping the kiln room floor...
The pyrometer is all over the map, so I pull out the thermocouple and swap in the other one from the small gas kiln, assuming (correctly, once it cools) that age and corrosion have worn this one away. But the cones haven't begun dropping at the bottom peep hole.
At 9 am, cone 04 goes down on the top of the kiln. Still no movement on the bottom. By 10 am, cone 1 is showing signs of softness, I've fiddled with the damper twice, the burners three times, and if I'm not at my wit's end, I can see it from there. My next two shows, not to mention a bunch of special orders, are riding on the success of this firing.
I was in the bathroom when inspiration hit. I finished and flushed and scrambled for the kevlar gloves, pulled out the peep plug, and sure enough: I'd put the cone pack in backwards.
Cone packs, as we use them, contain eight cones, set in two rows of four. I use cones 08, 04, 1 and 4 in front, 8, 9, 10 and 11 in back. If I put the pack in back-to-front, that meant I was looking at the wrong cones. And in fact, cones 08 through 1 were all down back behind the front rank; the only cone standing was cone 4.
Which meant my firing was perfectly on track, and I stop could stressing and go back to mixing glazes, making tests and mopping the kiln room floor...