Sunday, December 10, 2017

A Good Firing of the Wood Fired Kiln!

We fired the wood fired kiln on Tuesday of last week and it was a great relief on Friday to remove the door bricks and discover that it had been a good firing. We have had days of hot weather here, and the 10 and a quarter hours of getting to temperature had been rather arduous. I drank about 2 litres of water through the day whilst stoking, and also had several cups of tea!

People sometimes ask me "if it feels like Christmas" when I open the kiln. I was thinking about that when I opened it this time and I realised that the process of wood firing is much more like Easter. There is a real ordeal involved in the firing of a wood fired kiln. A week or so of glazing pots, packing the kiln, and chopping wood, and then the intensity of the hours of the firing itself, followed by a nearly three day wait for the kiln to cool after temperature has been reached. Removing the first bricks from the kiln door is usually done in the stillness of early morning.

My thoughts, as I removed the door bricks, were of the women arrived at the tomb early on the first Easter morning who found the stone rolled away!

I was greatly anticipating seeing how these jugs turned out. They were made with a clay that I am testing at the moment that had showed great promise in the tiny samples that I had put in the previous firing of the wood fired kiln and in the electric kiln. The jugs were the first "real" objects that I had made with the clay, and I was anxious to see how it would cope with the realities of fire and flame and very high temperatures. Happily it performed beautifully, and the clay has a lovely warm colour where ever the fire hits it directly.

The jugs are between 6 and 7 inches high (152 - 178mm) and have a shino glaze inside.

Porcelain Bowl
I tested a rutile glaze in this porcelain bowl. The bowl had an iron bearing under glaze on the inside only. The glaze gave pretty pinks, blues, and violet shades on the outside, and an exciting waterfall of blue flecked with cream, pink and brown on the inside! The bowl measures 4 inches high by 7 1/2 inches wide (102 x 190mm)

Pouring Bowls
I made some pouring bowls, and enjoyed the playful form, with the pouring lip and eye embellishments. I tried various glaze combinations.

The pouring bowls are approximately 4 inches high by 6 in diameter (102 x 152mm).

Runny Ash Glaze
I like glazes that don't just sit still when they are fired, but sag, pool or flow. Wood ash contains silica and useful fluxes that include potash and calcium and traces of other minerals too. Ash will make a glaze all by itself if applied to a pot, but improves if other things are added to it, such as clay and feldspar. Containing just 15 percent of unwashed wood ash, this ash glaze has so many "other things" in it, that it is called a "fake ash" glaze. It is Van Guilder's "fake ash" glaze from John Britt's Cone 10 High-Fire Glazes book. Flowing over a white matt glaze as it does here, it has the look of a spreading wash of very wet watercolour.

The bowl measures 7 1/2 inches high by 9 inches wide (190 x 228mm). The ash glaze was applied to the top quarter of the bowl after the white matt glaze had been put on. I was interested to see how the ash glaze ran further where it got the most heat.

Strontium gets its name from Strontian, which is a town in Scotland where this alkaline earth metal was first discovered. Strontium carbonate behaves very like calcium in a glaze, and can replace it in glaze recipes and is superior to it in some ways, however it costs a lot more, so it is not commonly used. One property that it does have that makes it useful on "special occasions" is that it does assist in producing some lovely alkaline blues from glazes that have copper in them. It is almost as effective as barium carbonate in this regard. Strontium carbonate sounds like a deadly chemical from the nuclear industry, but Strontium carbonate is non-toxic, it is the isotope Strontium-90 that is dangerous, and this is not what we are dealing with here!

This 7 inch high (178mm) jug has a glaze on the outside that contains 4 percent copper carbonate and nearly 32 percent Strontium carbonate. I love the scatter of dark crystals where the glaze is thick. The glaze recipe comes from an article in Ceramic Arts Network Daily, leaving bariumville replacing barium carbonate in cone 10 glazes. The inside glaze is a reliable tenmoko type glaze.



I sieved wood ash and feldspar directly onto this stoneware pot, and left it to the flames to make a glaze of it. I like the texture where the feldspar has melted with the wood ash. The pot is approximately 10 inches High by 10 inches in diameter (253 x 253mm).

Angelic Musicians!
Christmas is almost here, so I made a merry group of Angelic Musicians who play together on a variety of heavenly instruments that bear some similarity to earthly saxophones, trumpets, and medieval instruments. The musicians range from 4 to 5 inches in height (102 - 127mm).


Rhonda said...

I say !! What beautiful work Peter, superb and you even made the musical figures. What a feeling it must be, to have such a successful firing.

cookingwithgas said...

Happy Christmas! You had some great results that would make anyone happy. Best M

Linda Starr said...

Yippee for the good firing, especially love the rutile bowl and the turquoise jug with the strontium glaze exterior, merry christmas to you and Laura, hope you have lots of holiday sales.

Sue said...

I'm loving this lot of firings. How very clever you are.
I enjoyed reading the Easter analogy with the opening of the empty tomb. Except it wasn't empty on this occasion - what a shock that would be!
The angelic musicians are cute. ��
I wish you and Laura a pleasant and merry Christmas ❤
Love from Marion and myself.

Peter said...

Good Morning Rhonda!
Lovely to hear from you, thank you for your good cheer and encouragement!

Hi Meredith,
Happy Christmas to you too! Happy indeed regards the firing, it is an enormous relief to have some good work, I was a bit worried about it!

Hi Linda,
Merry Christmas to you and Gary! I am a little in love with copper blues and greens, and I am looking forward to playing further with strontium glazes. This one also has just a hint of pink in some areas due to the reduction atmosphere, and it is rather lovely when peered at closely!

Good Morning and Happy Christmas Sue and Marion,
I'm glad you enjoyed the Easter thoughts, it really does feel like that for me. A mysterious and deep process making pots if one thinks quietly about it. There is something very nice about the rhythm of potting that makes a little spaces in life to ponder and reflect about things!

srgb said...

Dear Peter this is such a bright note given the trouble you have had health wise and I do hope its not just lingering in the background, your studio must look a very different place to when I visited you a year ago.
It is so good to see such clever work.
Merry Cmas to the both of you.

Peter said...

Hello Bob,

Lovely to hear from you. Yes, definitely good to be achieving something and making some progress with the potting. It certainly has been a year full of light and shade, but each firing of the wood fired kiln is a morale boosting fight back! I seem to remember that you visited not all that long after my shoulder operation, and the main difference in the studio now is that there are obvious signs of new work on display and other work in progress at various states of completion around my wheel and in the glaze room. It feels like the place has a pulse again!

Merry Christmas to you both, and a very happy new year!


peter johnson said...

Dear Laura and Peter,finally,I get around to a message..cracker jugs,absolute crackers
sorry I missed you as I departed in the wee small hours,almost 3 months back,
missed goodbyes with lotsa people,thanks for everything,you lovely pair.
the Xmas parade is sliding down waipu main I tap this out..i also had a wood firing,new little FASTFIRE woodkiln,built entirely from two recycled electric kilns,
about a week back,nothing as exciting as your lot..where do I find your email.??
have a lovely Xmas,new year,and I shall attempt same.xoxox

Peter said...

Hello Peter,

Lovely to hear from you. I hadn't realised that you had left town, I had been meaning to catch up and have a pizza together at the Karitane Store now that we are in the summer season! Sorry you have migrated, but very nice to hear from you, do stay in touch!

Really pleased to hear that you are wood firing in re purposed electric kilns (the electric kilns will have quite a thrill having real flames rather than radiant heat going through them!
Our email is opogallery AT gmail DOT com (with necessary adjustments to make it work!). I'll try to email you, not sure which email you are using these days, but I'll see if I can get a message through to you!

Very Best Wishes from us All at the Old Post Office. Happy Christmas and New Year,

Peter, Laura and Nigella Stopit

Anonymous said...

Beautiful firing, Peter! Best to you for 2018! Cheers, Owen in Oregon

Peter said...

Hi Owen,
Good to hear from you. Happy New Year to you too! The kiln is loaded, wood prepared, and a firing planned for tomorrow, so we will bring in the New Year with a puff of wood smoke!