Shino's come to life

A soft cadenced yet incoherent crackle, continually chimed under the naked moon. Intent eyes, heavy breath, sweat dripping  faces, dimly lit by  the flames radiating from the burning logs in the kiln; steady hands griping chunks of dark brown wood, ready for the signal to thrust them into the inferno, and the night silently watched as it glided away.

We, the wood firers, in silent coordination gazed at the white blue flame emanating above the wood kiln flickering across the blanket of the deep endless night. That was a night in late August when the wood kiln that had stood dormant for some months had been resurrected for a 30 hour firing.

Our instructor;  Raania and us; the second year ceramics students, had already prepared the kiln, loaded the work a day before and the wadding we used had sawdust mixed in it as a filler which was a very successful idea; during the unloading of the kiln, the waddings very easily fell away and did not stick to the work. We also placed two cone packs inside the kiln (one near the stoke hole and the other at the opposite end at the peep hole) and sealed it with soft bricks and mortar made from grog, fireclay and sodium silicate. Each cone pack was loaded with four cones: r02 (1120°c), r5 (1196°c), r8 (1263°c) and r9 (1280°c).

We stared early at 6:00am with two gas burners inserted into the firebox with a medium flame. The idea was to heat the kiln and dry it up before the actual wood firing started. By 7:30am the kiln had started reacting with thick black smoke which we wanted to force out of the kiln because that was actually the wetness of the kiln and the work inside. From this point onwards, till the end of the firing one major factor to constantly keep in close contemplation while stoking was to ensure that there was an even fire throughout the entire firebox. The further away we would start the fire, the better it would be because that would, to some degree, insure that there would be an even firing throughout the chamber within and the work at the far end would also get the same treatment as would the one nearer to the stoke hole.

By 9:00am the pyrometer indicated a 100°c and we gradually started with a small wood fire mainly using thin wood. The goal was to build up a coal bed to retain heat and have substantial wood fire to raise the temperature. Dampers had been installed but were kept open and all air ports were partially closed. It took us another hour to reach 350°c and with regular stoking of thick and thin wood on regular intervals or just by eyeballing if there was need. Reason for this was that the thick (keekar) wood was not catching fire swiftly enough till this time. Within the next half an hour, when the temperature was soaring a 580°c, we had removed the gas burners completely which resulted in a substantial drop in temperature but we started heavy stoking and managed to regain 570°c by 11:00am.

From there onwards we stoked wood heavily relying mainly on thick wood with little amounts of thin wood for faster burning and more coal for higher preservation of heat. During all this time the kiln kept to good behavior and the pyrometer displayed a constant and steady rise in temperature. When we reached 791°c, around 1:00pm it was time for the first body reduction.

According to Raania, the body reduction was to take place before we reached 1000°c, near and ideally between 800°c and 900°c. To start, we pushed in the dampers, closed all air ports and choked the stoke hole with a lot of thin and thick wood. Here, within the next 5-10 minutes Raania indicated the appearance of a reduction flame. This was a darker, deeper flame; with thick black smoke smothering and hugging the kiln and the flame was pulling and forcing itself out of the stoke hole. It was as if it was desperate and yearning for air to breathe. We kept this going for an hour and around 2:00pm we slit open the dampers.

After this, up till 5:00pm when the temperature had reached a 1000°c we stoked irregularly mostly eyeballing if there was need to stoke or not. This actually worked because there was a consistent rise in temperature. At a 1000°c we raked the coal bed to let in some air because there seemed to be some natural reduction taking place but keeping in mind not to make too much ash fly. Around 6:44pm when the pyrometer spoke an 1100°c we checked our cones as the pyrometer was said to be 50° off. Both r02's were down. Then by 8:00pm we checked our cones again and both r5's were down as well.

Apart from the cone packs Raania had also installed 5 clay rings on one of the bag walls; the first two of which were not glazed. All of these were also dipped in another clay with iron rich content. The idea behind pulling these rings out at different temperatures was to be able to determine what the work inside looked like and to be able to examine the difference at different temperatures.

It was about 8:15pm when we had reached 1200°c and we pulled out the first ring. The clay body had vitrified, it was a little rough and the area with the iron content clay had a grey brown shadow. 9:25pm the second ring was pulled out which also had no glaze but it did display a natural shine. 10:00pm the third ring was pulled out. This had glaze application. These were shino glazes with ash content in them so in this firing, specifically, it was not necessary to have ash, salt or soda flying around the kiln. This ring showed us that things inside were pretty good and with a little more temperature the ash glazes would be able to dance to their optimum and for a good ash melt one generally requires a 1220°c to a 1260°c.

In the next half an hour ring four was retrieved with good results and the two remaining cones on the bag wall seemed soft, however cones at the back; in front of the peep hole were already down which meant that more fire was needed near the stoke hole.

 It was around this time that the kiln stopped responding to us and the temperature started to stall. Ring five was retrieved around 11:15pm and it did not display any visible difference when compared to ring four. This continued till 11:30 and we decided a change of strategy was critical as the rise in temperature was crucial at this time; so we decided that instead of stacking in a lot of wood (which would have been my first impulse) we started to stoke a very minimal amount of fast burning thin wood. According to Raania we were to make the kiln hungry so that it would beg for more wood, and this worked!

r8 and r9 were down by 12:15am and by 1:00am we started the process of reduction cooling which was the most important aspect of this firing. For this we closed all air ports, dampers were closed and the firebox stuffed causing a major reduction. By 2:30 to 3:00am we continued stoking but reducing the quantity slowly. In the end we sealed the stoke hole leaving it stuffed with mainly lots of slow burning thick wood.

Initially Raania had planned a 5 to 6 hours period of reduction cooling but by the end we couldn't execute the plan. The reason for this emphasis was basically because, although, the body had vitrified and glazes had melted at 1280°c, all the unexpected flashes and beautiful fiery hues would appear in the period of the reduction cooling. Raania had also placed a bowl of salt in between all the work.  Its main purpose was to make the fire more volatile and create the flashes that she wanted on her work.

While firing we did cycles of reductions and oxidations constantly according to the rings that were pulled out. Preferably we wanted to acquire two major reductions: the first was a body reduction and the last was near 1266°c.

I have taken part in three wood firings up till now and every time I have felt that it was my first and every thing that I have learnt has taught me to respect all that I still have to discover. I have learnt that one needs to have faith and trust in the kiln. Sometimes one needs to have patience and in the worst of situations one needs to learn how to lean on intuition rather than walking blindfolded behind the general principles. I do not think that in any kind of firings when I have achieved my required temperature have I ever felt such joy and pleasure that I have felt in wood firings.

Wood firing is extremely unpredictable and requires constant attendance.  I feel there is so much more involvement of the firer in these firings and only those who truly love, like to enjoy and take pleasure in their work would want to wood fire it with so much love.  It may not appeal to some people but to some, it is the time they come alive.

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