Higham Hall College, October 2012

Despite perfect weather for firing this was not our finest hour, or rather 44 hours. I am inclined to put its failings down to wet wood. We had a ton or so of 60cm long split logs nice and dry in the garage and 4 bundles of offcuts ordered of which only 2 had been delivered. Despite being under tarpaulins the seemingly continuous rain of the summer had left the wood at 30% moisture content (according to Rob's moisture meter gizmo) and the final 2 bundles delivered the day before firing were wetter than the driftwood I pick up on the beech at home.
The lovely Will arrived on Sunday to chainsaw up the bundles and agreed to return on Monday to deal with the second lot. Size matters when it comes to chainsaws, I only wish we'd found Will for the last two marathons of sawing - we were knackered then before lighting the first match. This time we were knackered from the continual rearrangement of wood on and around the kiln as we tried to dry it out. These bundles were of very small bits, far too small for the later stages of firing, and no time to sort it either. Not a perfect arrangement but better than no kiln at all!
Sunday we chopped and stacked wood, straightened the chimney with longer angle iron and brackets and threaded bar top and bottom, and set up tables and the wee pop up marquee which extends the shelter in front of the kiln. Monday was loading day although some precious time was spent on wood. It's a long slow process and so important. I'm not sure we'll ever make the best of it. We each have our own preferences for wadding, dry/sticky, white/flashing, course/fine, and many of the wads fall off by the time the piece reaches the person doing the packing crouched in the bowels of the kiln. More research needed on this. I like a fireclay/course sawdust mixture which flashes nicely and sticks well  to the pots, but it also sticks to hands which is not appreciated by porcelain.
   By the time the light was fading it had already been a long day and there was still dinner to make and the door to brick up and some clamming of holes to do. It was a tighter pack this time. More shelves, lots more pots, one more firer (5 of us). We had put the gas burner on  through the damper at the base of the chimney for a few hours earlier, which was a good move as it dried and warmed up the chimney to improve the draft. It gets very wet sitting through 6 months of Cumbrian weather between firings.
Overnight on gas into the firebox took the temperature to 100? Then we lit a small fire in the grate at 10am and so began the rota of 4 hour shifts, 6 hours off for the next 45 hours.

The final firing

The final firing of this little kiln that is.
Number 27, 7th July 2012

That was the Wimbledon weekend when Andy Murray finally made it to the final and I realised on Friday that I had to fire on Saturday in order to watch the tennis on Sunday. Only the realisation happened on Friday evening after he won the semi, which I had been watching instead of packing the kiln (keep up there).

If I packed in the morning and fired into the night I would get enough sleep to be awake again in time for the final. That's if the forecast bad weather held off long enough.

Another fairly loose pack. Flat black clay tiles on the bottom shelf 'wadded' on silica sand, two more shelves, large platter on the top shelf. Cones 7, 8, 9, 10.

Midday Saturday, high cloud, gusting from the North and North East, a bit chilly really but DRY and NO midgies.  Lit the gas to get it going. The gas blew out so for the first time I started with wood alone. Usually the kiln has absorbed so much moisture from the humidity that I have to dry it out for at least a couple of hours on gas. However whilst the covers have been going on at Wimbledon and England is doing an impression of Atlantis this corner of The Misty Isle is having a drought.

Five hours later with the pyro reading 993ºC I reckoned it was as good a time as any to let the kiln do a fast fire!
After 7 hours it was at 1158ºC after which it started to slow a little
After 8 hours it was at 1168ºC but touching 1200º so I put the soda in, about 250g
          9 hours               1212ºC  cone 7 bending
         10 hours              1220ºC  cones 8 & 9 softening, getting a good temperature rise with thin pine branches about 2 - 3 inches diameter.

After 10 and 1/2 hours it reached 1251ºC with cone 10 softening. End of firing.  At least 3 hours shorter than normal.

Bed, sleep then sit back and watch Andy lose! But just like woodfiring it's the taking part that counts not just the results.

The firing, continued...

 Lovely new cladding on the kiln.  Fire clay, vermiculite and a bit of sawdust. It was like plastering with porridge only less salty. And had the added bonus of making the arch look a little more professional. The green posts are ex-tennis court posts rammed into the ground, wedged with bricks and wired together over the top in an attempt to counterbalance the desire of the arch to become a pile of bricks.

And lo and behold the whole construction held together, rather well actually, and looks a whole ot better than the ware chamber.
The new arch is a proper roman arch and considerably higher than the old one. Had we thought about it we should have lowered the supporting walls by a course or two. We weren't sure how this extra volume of the fire chamber would affect our ability to reach temperature. The results, after 40 hours of stoking dry pine slab wood was cone 10 melted almost throughout the chamber (middle back cone 10 was just down). To my eye, the best firing yet, some lovely natural ash glaze, good crusty effects in the firebox, not too many collapses, not too much reduction. We could spend more time building up ash deposits in the next firing being fairly confident of achieving a good temperature if we have good wood.
More detail of the firing log soon. photos next

Anagama in Cumbria

November in Cumbria is not the best time for a firing but it's still better than Skye has been this year.
Ten of us arrived at Higham Hall yesterday, 6 tons of wood waiting for us under tarpaulins and a sad looking kiln. Last years winter frost has caused a bit of heave and the arch is looking distinctly flat. Should hold up and Gavins big pots are strong enough to withstand a collapse so they're at the front!  
This is a much tighter pack than last year. Lots more pots, new shelves and props. About 4 hours to pack (photos later) and brick up the door. Gas on low overnight to dry it out after 14 months of Cumbrian weather. 120 C at 6am this morning. Small wood fire in the ash pit and up to 240 C by 10 am. That's me off shift until 22.00 but we're aing for 800C by 18.00.

Firings 16 & 17

I'm writing this in the middle of the 3rd firing since the rebuild.
The first, no. 17 zoomed up to 900 in 7 hours (weather not a factor, overcast and light breeze) then stalled around 1100 for about 4 hours. After 13 hours I managed to coax it up to 1200. Where it stuck for another 2 hours reaching 1240 tops but acheiving cone 9 down.
The results included some lovely carbon trapping in a soda ash glaze I was testing.
For firing 18 I attempted to follow the previous cycle to get the carbon trapping effects again. The weather was breezy from the south west so not too different.
I reduced for an hour at 900 but not a heavy reduction, as the breeze was blowing directly into the firebox. The kiln stalled again between 1120 and 1170 for about 5 hours. Reaching 1218 tops but with cone 9 only just starting to go after16 hours, by which time I was completely gone, so clammed up and headed for a hot bath.
I then had to wait 2 whole weeks on an annoying holiday before I could unpack this kiln. That's the trouble with non potting partners they don't really understand what's the priority. Actually I did prize open the lid for a quick peek just to reassure myself it wasn't a disaster, that would have really spoiled the holiday.


I should mention here the benefits of non-potting partners - coffee, breakfast, lunch, dinner, cups of tea, that magnificent cold, cold beer at 6 o'clock with the kiln at 1200 Centigrade after 13 hours of continuous firing, all brought to me with barely a hint required.