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).

Monday, November 20, 2017

Open Studio, Fish, Firings, Flops and Fun!

We were recently part of a local craft day and had our place open to the public with me demonstrating on the wheel, whilst Laura talked with people in our gallery. We had a busy few weeks getting work ready for the day, and Laura  painted some really lovely imaginary fish. Most of the fish were designed to hang on the wall, but I made little wooden stands for some of the others.

Sadly we may have only had 25 people through in total, so sales were a mug, a small bowl, and a card, which was a bit of a disappointment, but we are thankful to those who visited and we have got the place well stocked up for the summer season!

I had intended having some new porcelain paperweights for the open day, but only 2 of the 11 paper weights enjoyed their glaze firing... the remaining 9 were either under fired, over fired, or just plain stubborn and would not grow crystals! It was a complete contrast to the excellent firing I had the time before!

I contemplated trying to get another kiln of crystalline pots fired before the open day, but was too short of time... so had to do what the sign a the end of our street says...and Stop!

Instead I glazed a kiln load of 2 large, kiln filling pots and a medium sized one as I was desperate for new work to go to the Potter's Co-op for a window display that we were scheduled to have in the days running up to the open studio here.

 The jug, or pitcher, on the left is about 19 and a half inches high (49.5cm).

I used a Cone 3 glaze of my own, that I had tested on something small a few years before, but had never put on anything large. I was delighted by the result. The glaze is an alkaline copper blue and it was nice to see the colour variation where the glaze was thick or thin.

Laura snapped this photo of the Co-op window display on her phone.

Once the Open Day was over with, I spent the next week glazing pots for a firing of my wood fired kiln. The studio soon fills up with pots in various states of glazing, and it is quite a art finding enough space to fit everything.

 It is a relief to get the pots out of the studio, and the kiln loaded.

 The kiln fired really well, but....

I would love to report a great firing, but it wasn't... I got things too hot! I over fired many of the pots due to a series of errors and a poor decision on my part, so I lost almost everything that was copper red, and some celadon pots were very unattractive.

In spite of all that, there were some gems!

These small porcelain bottles are probably my favourite things from the firing.

 A shino jar.

 A 6 cup coffee pot (or teapot if you would rather!)

 A tea pot. The handle was made up from three tubes that were thrown on the potter's wheel, then split in half.

Shino seems very forgiving, and can cope with a wide range of temperature. This is a spoon organiser.

 And a tiny 3 inch high jug (7.6cm)

 I like this urn. It isn't quite the colour I intended, but it is dignified and peaceful. The lid was quite difficult to make, as it has to fit inside and outside the pot.

We were delighted to have a visit from a Sarah, who is a Christchurch potter. She spent 4 days working away in my studio with me, and it was nice to have company in the studio and 2 wheels going at the same time.

I am busy getting more work ready to fire in the wood fired kiln. The unusual looking thing on the right of this photo is a porcelain candlestick. I rather enjoyed making it, and hope to develop the idea further and make a candelabra for several candles.