FIRE and FIBRE

Collaborative artworks and installations by members of the Scottish Potters’ Association and the Scottish Basketmakers’ Circle at the Collins Gallery, Glasgow

19 November – 17 December 2011

opening Tuesday-Friday 10-5 & Saturday 12-4

come to the opening from 12 noon on Saturday 19 November

see  Fire and Fibre, Collins Gallery Glasgow 2011 opening day and exhibits

Collins Gallery, University of Strathclyde, 22 Richmond Street, Glasgow G1 1XQ   +44 (0)141 548 2558   collinsgallery@strath.ac.uk

 

Selected Exhibitors/Partners:

Anne Murray (SPA) & Caroline Dear (SBC)


Jane Kelly (SPA) & Jan Miller (SBC)

Working on 3 forms which aim to place plant fibres and fired clay into different contexts: water, air and earth.

 

A willow duck bender with ceramic eggs.  Based on Tinkers’ Benders, will be a traditional willow structure woven with hedgerow foliage. This is an environmental project intended to replace the plastic duck house on a local Penicuik pond.  Unlike plastic the willow has potential to root into the pond bottom to become a stable and comfortable home for the resident ducks. The eggs will be in stoneware clay, raku or porcelain.

A hanging structure made from pieces of Scottish bogwood  supporting delicate ceramic, glass and fibre seed pods and textural forms. This will be supported from a ceiling or wall.

A willow hurdle screen supported by wire and wood. Woven with ceramic flowers and leaf shapes, and with some flower heads in glass, paper or clay.


Bill Runciman (SPA) & Eileen Runciman (SBC)

 



Anne Lightwood (SPA) & Jon Warnes (SBC)

 


Kerstin Gren (SPA) & Tim Palmer (SBC)
  


Jenny Mackenzie Ross (SPA) & George Legg (SBC)

 


Maralyn Reed-Wood (SPA) & Heather Reddish (SBC) 


Johan Carslaw (SPA) & Ailsa Morrant (SBC) 


Kirsty O’Connor (SPA) & Anna King (SBC)

 


Kirsty O’ Connor (SPA) & Pip Weaser (SBC) 

10-Kirsty-O'Connor-Pip-Weas


Frances Drewery (SPA) & Pip Weaser (SBC)

 


Fran Marquis (SPA) & Georgia Crook (SBC)
 


Fran Marquis (SPA) & Sue Beavan (SBC)
 


The exhibition will comprise over 35 artworks and installations in which members of both groups have collaborated to complement and push the boundaries of each other’s practice.
Individual makers will also be represented by  a range of smaller pieces which will be available for immediate sale. Ideal for festive presents!

 

Exhibition background

“This exhibition follows from a workshop at Cromarty on the Black Isle in the autumn in 2007 when the Scottish Potters’ Association (SPA) enlisted the help of some basketmakers in the Scottish Basketmakers’ Circle (SBC) to make a “Basket Kiln”. The main structure of the kiln was created in woven withy which was then covered in clay. Once the kiln was fired, the clay dried and the basket burnt away. Timing was crucial so that the clay was dry enough to hold its structure before the basket burnt in the high firing temperatures (around 900 degrees C). Although this was mainly an SPA event, some SBC members were also involved, leading to planning an exhibition together and participants of both organisations attending each other’s workshops.

The first exhibition in this series was Pots & Baskets at the Bield Blackruthven in October 2009.  It was an interesting and successful exhibition but felt like a starter for more experimental work. So this exhibition at the Collins, Fire & Fibre, deliberately set out to widen the scope of collaborative projects.” -Fran Marquis, Scottish Potters’ Association


The Cromarty Kiln – Joint Scottish Potters’ Association and Scottish Basketmakers’ Circle Project

Article by Veronica Newman (SPA) and Tim Palmer (SBC)

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At an Applied Arts Scotland conference in 2005 Jane Wilkinson of the Scottish Basketmakers Circle gave a talk that finished with a picture of a burning wicker man. This, with the earlier discussion about collaboration between different crafts, led to the thought that there should have been some pots firing in the flames.  Subsequent contact with the SBC led to correspondence between Veronica Newman, then Chairman of the Scottish Potters' Association and Tim Palmer, a basketmaker near Inverness, about the possibility of constructing a willow kiln that would fire pots. He had worked with Andrew Appleby, an expert on Orkney on prehistoric pottery and had gained some experience in so-called 'primitive' firing methods.

The specification for the kiln was that it should incorporate basket work and be capable of firing to at least low earthenware temperatures. There were a number of factors to consider:
- A pure willow structure would have to include a lot of willow in order to reach and maintain the required temperature. 
-  The temperature rise would be very rapid, and would probably lead to unacceptable loss of pots. 
 - Setting fire to such a structure would require a wide open space, and the proposed venue - The Cromarty Arts Centre - was an old stable block surrounded by trees.

Some research into willow kilns led to an article in Ceramic Review by John Nuttgens (CR 2003:199: 47-49 ) describing a kiln used for raku work built at the Eden Project. This used a willow framework covered with china and ball clay mixed with sand and woodshavings. The article pointed to certain difficulties in the construction and firing of such a kiln. From a basketmaker’s perspective, the illustrations of the willow structure suggested that the materials used were thin, and the weave not particularly strong, an important factor in the collapse of the prototype. The addition of grog and combustible material was common practice in the stone and bronze ages and had been described by Andrew Appleby (Ceramics Technical, 2006; 23: 49-52 ,CR 2005; 211: 52-54).

After consideration of various architectures, a simple up-draught kiln was decided on  because of the ease of construction of the firebox and willow former for the body of the kiln. A three-quarter scale prototype was constructed and fired successfully at the end of June 2007 at Fursbreck Pottery in Orkney, easily achieving 970oC. The final design was essentially unchanged from the prototype and was a bottle shape kiln 1900mm high with a base 1000mm diameter. The chimney narrowed to 250mm for the last 400mm, giving a firing chamber 1500mm high. There was an arch 600mm wide kiln at the bottom of the framework. The kiln was positioned over a pit within which was built a framework of firebrick and kiln shelves that would be the floor of the kiln. The kiln shelves were positioned at the level of the top of the arch. The firebox, 1000mm long and 600mm wide, was built extending from the arch. The ash pit was an extension of the pit under the kiln floor. The walls were made of firebrick, the fire bars of reinforcing mesh for concrete structures, and the roof of kiln shelves. There was an insulating layer of earth and turves.

The weaves for the framework were those used in Irish and Scottish pack creels, (Joe Hogan, Basketmaking in Ireland, pub. Wordwell 2001, ch 2), using willow supplied by Blencogo Willow in the north Lake District (www.blencogowillow.com). Creels are robust baskets used as panniers for pack animals, or back packs for collecting peat and seaweed. 
The mixture used in Orkney for the clay covering was a local (Minehowe) clay mixed with 25% builder's sand and 25% combustible material. The latter incorporated sawdust, wood shavings and grass clippings. The grass improved the plasticity of the  final mix but was not available for the Cromarty Kiln. The clay covering was built up in layers to a final thickness of ~ 100mm, reducing to ~75mm at the top of the chimney. Firing the prototype had shown that a layered construction was better than using 'bricks' as the cracks that developed were not full-thickness and were less likely to cause structural instability. The door was constructed with sloping edges so that the bottom fitted into the kiln and the sides and top overlapped the outside of the body. This arrangement ensured that the weight of the door kept it pressed into its seat, and the reverse slope on the bottom stopped it sliding out at the bottom. Because a large pot (nearly 500mm diameter) was to be fired, the door was constructed in two sections, 1/3 and 2/3 of the overall size, with the slopes of the sides such that the larger portion came out first. The door sections were separated from the body of the kiln by a layer of newspaper and lifted out by means of bone handles set into the clay. The clay used was a mixture of material of uncertain qualities, but mostly grey and probably earthenware. Again, sand or grog and combustible material was mixed in, to a proportion of 50:25:25, but no grass was used.

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Construction of the willow framework took one day. The bottle was divided into two sections at approximately two-thirds its overall height so that the bottom section could be plastered and allowed to dry before loading the kiln from the top and finishing the kiln by replacing and plastering the chimney. Preparing the site, the clay mixture and plastering up to the base of the chimney took four people two days, led by Bärbel Dister, the SPA workshops coordinator. The most efficient method of mixing the clay was found to be treading - initially in a bath and then finishing the mix off on a tarpaulin. The initial layer of clay was forced into the weave of the willow, subsequent layers being applied by hand, and the final layer trowelled smooth with a plastering float. No decoration was applied although votive figures were placed on small ledges on the outside of the kiln. Impressed decoration had been used on the Orkney kiln to see if it would help drying, but it merely concentrated the drying stresses, leading to more severe cracking in the decorated areas. The lower portion of the kiln was built a week before the workshop in order to allow it to dry out, but the wet weather meant that there was no significant drying over the week.

On the first evening of the workshop, the kiln was loaded with a variety of pots and figures brought by SPA members and the chimney put in place and plastered. The kiln was then lit. The intention was to keep the temperature between 100o and 200o C overnight, but at about 03.00 it started to rain and the kiln was covered with a tarpaulin. Firing started again at 09.30 the next morning with a temperature of 200o C being maintained until 12.30. Cracks appeared as the clay dried and were filled with clay mix.

The temperature was taken up from 12.30 hrs. At 400o C (14.00 hrs) the willow burned away and the temperature rose to 600o C over a period of 5 minutes. This temperature was maintained by vigorous stoking, combined with the presence of wood shavings and sawdust packed into and around the pots, the large pot acting as a sagger. The test kiln had experienced a similar rise in temperature but this was followed by an equally rapid fall. The rapid fluctuation in temperature had caused some damage to the pots. The temperature rise continued, with 1000o C being reached at 15.30 hrs. The kiln oscillated between reduction and oxidation, with corresponding falls and rises in temperature. 1100o C was reached at 16.00 hrs, and 1111o C at the bottom of the chimney by 16.10 hrs. Readings at the level of the kiln shelves were consistently 20-30o C higher. When in reduction, flame reached 2 or 3 feet above the chimney. The kiln was maintained at temperature for 15 minutes and then the firebox filled with wood. Wet seaweed was put down the chimney and over the firebox, leading to heavy reduction. Despite this, the temperature at the chimney base rose further, to 1148o C, before falling over the next 30 minutes to 950o C, and to 700o C by 18.00 hrs.

The kiln was left overnight to cool and opened at 14.00 hrs on the Sunday. A terracotta brick that formed the main support for the floor of the kiln had sagged and broken. The large grooved ware pot, made with Orkney clay, had slumped dramatically and broken. Some of the pots around had fused to it. The combination of wood ash and the salts from the seaweed had glazed some of the pots and welded pieces of kiln shelf together. All the pieces apart from the grooved ware pot had survived and showed various surface effects resulting from the reduction and salt/ash glazing. The grooved ware pot was glazed and in places the clay appeared fused.

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The results achieved with the Cromarty kiln indicate that Iron Age potters were capable of achieving significant temperatures. The design of the kiln is similar to Roman kilns excavated in Yorkshire (Stephen Harrison, personal communication) that also show similar impressed patterns on the inner surface. It would have been preferable to allow the Cromarty kiln to dry further before firing, especially as the mix was wetter than the Orkney kiln. However, the weather and timings conspired against this. The wall of the kiln had cracked more than the prototype but had fired to a greater depth. The handles for the door, made from bones, had burned away within the thickness of the door. Despite the cracks, the kiln was structurally sound after the firing.  The terracotta brick survived 970o C in the trial kiln, but not the higher temperature achieved at Cromarty. The temperature at the base of the chimney was 1148o C, and it is likely that the temperature at the base of the kiln was of the order of 1180o C. Iron age kilns would have probably have had floors of clay supported on brick piers which would not have suffered in this way. Both kilns were economical in their use of fuel, and fired quickly without too much difficulty. It was hoped that the cracks could be filled with a slip/sawdust mixture and the kiln used again but sadly the kiln has not survived the Scottish winter.

The Orkney kiln survived and was fired again at the 2008 SPA Autumn Gathering. This event included firing a kiln with turf walls, fueled with peat, as well as the second firing of the willow kiln. Attempts were made to vitrify the structure. These activities, monitored by experienced archaeologists, were designed to expand our knowledge of firing techniques used by the sophisticated inhabitants of the Stone and Bronze ages.

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Fire and Fibre, Collins Gallery Glasgow 2011 opening day and exhibits

Cromarty Pictures 2007  Jane Kelly, Scottish Potters Association

Pots and Baskets at Blackruthven 2009  Jane Kelly, exhibition organiser

Jane Kelly Penicuik Pottery homepage