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My Wood-Fired Kiln

I knew that one day I would have a wood kiln.

I started to put thoughts and then plans together for my two-chamber wood kiln shortly after returning from a three month period living and working in Korea in 1997. I had seen a number of traditional Korean multi chamber kilns during my stay and, together with my travels in the USA and the kilns I saw there, I formulated a design that was an amalgam of the various features that I had seen, drawn or photographed. I decided very early in my career that, once I had the necessary space, I wanted to try everything in terms of stoneware firing. Almost as soon as I moved to my present location just outside Rhayader in 1984, I built a large oil-fired reduction kiln. Soon after came the first of my salt kilns, to be followed by a bigger version in 1996: I knew that one day I would have a wood kiln.

phil rogers wood kiln feat 2 My Wood-Fired Kiln

The building of the kiln was a protracted affair. Block base, firebrick floors and fireboxes were laid before things stalled. There were – as there always are – pots to be made, commitments to be met; a couple of years went by before much further progress. Thanks to the help of my good friend Ken, a professional refractory brick layer and refractories manager at what was then British Steel, the rest was assembled in quicker fashion and by 2002 I had a functional kiln. Ken knew every trick of the trade, making the complicated seem straightforward. Since then he has helped me with every firing I have had. I have a great deal to be grateful to him for his loyal support and friendship.

L1009011 My Wood-Fired Kiln

My intention, initially, was that the second chamber might function as a salt glaze kiln. Indeed, it was fired to that end for its first six firings, but I was never satisfied with the results: even when the pots were good, they were really no different, nor any better, than those produced by my dedicated oil-fired salt kiln. I decided the extra work involved wasn’t justified and retained the second chamber as a wood fire chamber. Both chambers produce essentially the same work.

Acr53173234376640 496617 My Wood-Fired Kiln

Let me state from the outset that if almost 20 years of wood firing has proved anything, it is that I am not a natural born wood firer. Wood firing, for me, is a means to an end. I love the effects we get from the kiln, the colours and textures that are the result of flame and vapour on unglazed clay, but I can’t say I enjoy the process. My firings last between 36 and 40 hours which, by many wood firing potters’ standards, is not long. I’m afraid I simply haven’t the patience for anything longer: having worked with oil and gas for so many years, I can’t help but want the firing to progress, for the temperature to keep climbing. I don’t need large accumulations of ash. The flashed colour of passing flame interacting with the semi-glassy clay surface at 1300˚C – white heat –provides more than enough surface entertainment for me.

L1009558 My Wood-Fired Kiln

When my kiln was first ready to fire, I sat back and thought about what I wanted it to do, what direction it might take me. There were wood fire effects I knew I didn’t want. I had deliberately not built an Anagama: I didn’t want pots that were over-ashed, smothered in grit and those ubiquitous rivulets of glaze, running round a pot like fingers round a cup, meeting at an equally predictable shell imprint. I decided I wanted something a whole lot more subtle. I wanted, I thought, blushes of colour, subtle shades that echoed the flame as it passed by the pots in the kiln. I have seen a great many wood-fired pots particularly, but not exclusively, in the US where form has given way to surface. Pots without skeletons, flabby in a misconstrued Japanese style, that relied upon a flashy wood-fired skin to rescue an otherwise less than impressive silhouette. I knew if I were to pursue my path of no glaze, relying on flame and vapour alone, that form and orchestration would be paramount to the work.

Acr53173234376640862515 My Wood-Fired Kiln

I have always admired the pots from Shigaraki in Japan. I have Louise Cort’s seminal book on Shigaraki, from which I extracted several analyses of Shigaraki clays. The unglazed pots from the area are often a beautiful red to orange colour, a happy accident thanks to a higher than average alumina content in the clay. Consolidating these analyses into a single, chemical average, I then set about with the help of Seger – 19th century inventor of the pyrometric cone and a revolutionary glaze chemist – to recreate an equivalent using British materials.

It was one of those rare moments, at least for me, when something worked first time. I had a clay based on an English ball clay that had wonderful working properties and fired to those wonderful warm red and orange colours I wanted. As always when a potter embarks upon a new creative thread, advice is sought from wiser, more experienced heads. There are many very fine wood-fire potters from whom I have learnt by looking and absorbing, and to whom I owe a debt of gratitude. I remember well talking with, amongst others, John Leach, Nic Collins, Ken Matsuzaki, Joe Finch and, in the USA, Bill Van Gilder, Jack Troy, Mark Shapiro and Cary Hulin. The pottery fraternity is a sharing and giving one: long may that continue.

Acr53173234376640 2276313 My Wood-Fired Kiln

When one builds a kiln there are innumerable decisions to be made about size and configuration: chimney height, exit flues and fire boxes – so many things to consider. There are published formulae that one can adhere to, but these are really just guides. Having looked at and digested as many kiln designs as possible, I wanted to find a solution that was in some way my own: I wanted my kiln to be, at the very least, a little different. So – the mistakes I made? The second chamber is too narrow; the firebox is not big enough. I have had excellent results from it and then, as if purely out of spite, and for no other apparent reason, the next firing will be awful. The first and larger chamber has always been, by comparison, fairly straightforward. A cooler pocket in one of the back corners provoked a certain amount of consternation before I found some lower temperature glazes that could be reliably placed there; the chimney is probably too wide. All of these things are extremely difficult to rectify once the kiln is built and one inevitably ends up working around them. Firing – like all potters’ work – is a perpetual process of adjustment.

L1008989 My Wood-Fired Kiln

Wood firing is immensely hard work. The wood fuel I use arrives in 20+ tonne loads from a local saw mill. The waste slab wood must be cut with a chainsaw, moved and stacked near to the kiln. The natural born wood firer might find this a strangely Zen, self-centring, meditative therapy: I find it hard, back-breaking drudgery. All this of course is additional to the actual making of the pots. Glazing and stacking the wares in the kiln is one week’s work in itself. I have never been afraid of hard labour – making pots for a living is laborious, in the truest sense of the word – but as I slide with ever increasing speed toward my 70s, I tend to think my wood firing days may be coming to an end. I remain undecided: it would be a huge loss to my creative life not to be able to see those wonderful oranges and reds, the soft, sometimes metallic shino, the sublime green of a wood-fired ash glaze contrasted against the warmth of a toasted red clay, the decorative serendipity of the flame.

L1009096 My Wood-Fired Kiln

Firing with wood is like no other way to fire pots. The calm silence of the fire is so removed from the unceasing drone of the compressor that drives my oil kiln. The faint cracking and spitting of the wood as it burns at 3am, while the rain is horizontal or the snow begins to drift around the wood stack; the hot drinks at 4am, and the traditional bacon rolls and coffee for breakfast. It would be hard to give it up: we shall see what happens when the current wood pile is gone. Oh, to get another lorry load or not!?