48 hours into the firing. It is very hot.
I have slipped into a nice rythm of sleep in the day and work at night. I am sure a lot of people in the world do night shifts very comfortably, I was only not sure about myself untill..
As I was on my way to the pottery, I stopped to pick some cool things to drink and cookies etc. A friends, Srinath's chocolate shop opening .. CHOCO-LA.
I went past, and then turned around to get some delicious chocolate..
Once I reached the pottery the first thing I did was shared the yummmmmmmmmm chocolate with all before it melted !!
Well, the pyro was showing temperature fall and rise.. 1180 to 1250 deg centigrade.
There was a really nice build up of amber in ashpit two, in the ashpit three there was little amber. One could see the pots below a light spray of amber, that seemed to be almost dying(it looked that it did not have enough heat to keep burning.
Taking over firing kiln isnt easy. It s difficult to become one with it, if there are other issues to be encountered.
anyway, after an hour or so, I made several phone calls to Ray, and got the grip of the situation.
Essentially the firboxs have to go through a cycle of getting fed with a lot of wood, and then its given air and time to burn down. This burning down of the amber results in the beautiful run of ashs on the pots, that (pictures of pots will follow post 29th, the day we unload the kiln) one of the desired result from this kiln.
Todays night crew had three of us, Neha, Iber and me. Adil has not been well, so he decided to come the next morning. Ashwini who was on day shift joined us around 11pm to keep the energy going.
The attempt was to get the cone 10 at firebox two to go down. It would do so hopefully with rise in temperature... ah! and that wasnt easy.
kept trying out different combinations of wood, and the amount of wood to make the temperature go up. The pyro hit 1270 several times, 1280 say five times.. and 1297 just once, untill morning.. bugger did not go upto 1300. Leave aside temp on the pyro, inspite of over 30 degrees more temp, the cone kept up.... stubborn.
firing a kiln, at such high temperatures... when the wood is fed into the firebox, the wood takes heat from the chamber to catch fire... resultant is that we see a fall in the temperature on the pyro. After a while when the wood sitting there is burning, its starts emitting heat... resultant is, we see rise in temp on the pyro. if the wood is fed at the perfect time(right moment) the fall is less and rise is more, resultant rise in temperature!!
Thats what we are aiming at most of the time when firing kilns.
At other times, rather in Anagama, we maintain the reached temperature for several days to get the large amount of ash deposit on the pots.
just waiting to get back to the fire today evening:).
Oh! and what I forgot to tell you is that there was a lot of thunder and lightening.. just when it got dark and the lights went off. It was beautiful, with the place lit up with the fire in the kiln.
Only worry was how would i decide when to stoke without the help of the pyro??
ya, ya in olden days there was no pyro and the potters in China, Korea and Japan could tell, the temperature, by the speed at which a length of wood burned!
When I was in Japan. One of the studio artist, Max Hogetts, at Shigaraki Ceramic Cultural Park(SCCP) was doing an anagama firing. Of course with help from the SCCP staff and fellow artists. During one of the shifts, when we had all gathered around the kiln with dinner, a senior Shigaraki potter, Sawa San, took over the firing, as we all had food.
We all sat around watching the pyro and the fire. To my amazement he sat facing his back to the pyro. And he stoked the kiln at the right moment(explaination about the right moment is above).
What we saw was a constant rise in temperature!!!
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