Morgen Hall 3 Year Research Post in Ceramic Practice, Centre for Ceramic Studies, School of Art & Design, University of Wales Institute, Cardiff March 1998 to March 2001 (Report date: November 2000) Introduction For the previous 15 years I have been self employed making tableware which relies on the following technology: a kick wheel, a kiln, a pair of scissors and a roulette wheel. The work is thrown, but with the emphasis on turning and fine rouletted detail with slip pattern work. SLIDE 1: Two teapots SLIDE 2: Double walled ice cream dish with spoons Throwing & Turning I use a wheel as a versatile means of producing forms, where each individual piece has the potential to be developed in response to the previous piece made. SLIDE 3: Turning a leatherhard pot SLIDE 4: My kick wheel with clay chuck covered with cloth ready for turning. Rouletting A roulette is a small wheel with an engraved or embossed outer rim, usually attached to a handle, which can be rolled over leatherhard clay to impress a pattern. A roulette looks much like a ravioli cutter, but with different patterns on the outer edge of the wheel. The influence of 18th Century British tablewares gives an important example of how turning and rouletting a thrown piece can highlight form and enable clear space for surface patterning. After being dissatisfied with my own home made roulette wheels, (made from plaster, bisque fired clay and wood), I found that book binders use exquisitely made brass tools, which they call „ decorative farthing wheels¾. I bought one from a manufacturer¼s existing catalogue of roulette patterns and commissioned one to be made specially. When turning the base of a pot I leave a raised bevelled edge for the rouletted pattern to go on. The raised bevel makes for a more 3D pattern than if the rouletted pattern were pressed into the flat surface. Scissors I use scissors to create crisp edged paper resist pattern work. Newspaper shapes are cut and applied wet to the leatherhard pot prior to being sponged over with slip. Research Post In March 1998 I took up a three year research post at the Centre for Ceramic Studies at the Cardiff School of Art & Design, where I had previously attended the MA Ceramics course in 1983/84. For this research study I have chosen to look for an industrial technology for tableware production that has the potential for hand made interventions, thereby allowing an exploration of the crossover between the industrial and the hand made. I have been interested in finding ways other than throwing or hand building to make tableware. The main criteria I chose for directing this search included the ability to explore non circular form and to investigate more immediate ways of applying colour and pattern to the tableware. I also hoped to enable the production of these pieces in less time than my current very slow throwing , turning and decoration. SLIDE 5: Six ram pressed plates with various pattern work. SLIDE 6: Ram pressed plate with celery pattern from vinyl „plotter-cut¾ stencil. This new range of tablewares could then be mixed with the hand thrown pieces, which I will continue to make, thereby expanding the range of forms, surface treatments and selling prices. Choosing Appropriate Technologies 1.) For the Surface - The „Cutting Edge¾ of Technology In 1997 I saw a demonstration of a computer aided machine called a „plotter-cutter¾. To see a machine which can precisely cut any outline selected on the computer was nothing short of miraculous, especially for someone who had spent the previous 15 years cutting paper stencils with a pair of scissors. Plotter-Cutters have been used for many years by sign writers, who use sticky backed vinyl advertising for windows and cars. Memorial stone makers have also used plotter-cutters to make rubber stencils for sandblasting stone. Thanks to having the research post I was able to obtain a second mortgage on my home and in November 1998 I took possession of a Roland Cam-1 Pro Plotter-Cutter, plus a G3 Power Mac, scanner, printer and zip drive. I bought the following software: Illustrator 8, Streamline, Photoshop 4 and the interface between the computer and the plotter-cutter called Cutline. Although you can pay a local high street sign company to cut stencils by providing a floppy disc with the black and white design on it, this would not be cost effective for prolonged use. Sign companies may also be reluctant to cut anything other than their own vinyl, thereby restricting the variety of stencils that could be made. What is a Plotter-Cutter At its most basic, imagine a normal computer printer, but instead of an ink cartridge moving back and forth over the paper you have an ultra sharp small scalpel mounted on a swivelling head. Another feature of the plotter-cutter is that the material to be cut does not simply roll through the machine in one direction, but rolls back and forth as the scalpel moves across its surface, thereby enabling any shape to be cut. Materials to be cut can be up to 1 mm thick but must have a backing sheet attached, as otherwise when the blade sweeps over the same area twice, if the cut material is not stuck down, it can become caught up in the blade. Sign makers use sticky backed plastic vinyls which come with a waxed paper backing sheet. SLIDE 7: My „Roland Cam-1 Pro 300¾ Plotter-cutter What materials can be cut? I began to try cutting many different materials. If they did not already have a backing sheet I would stick them down to one. I firstly used re-stickable spray mount on acetate as a backing sheet, but I did have some problems with the spray mount being too strong to release paper stencils after cutting. I also found the spray mount to be messy. I was therefore delighted to discover that you can buy wide rolls of masking tape with a much lower stick surface than normal masking tape, called ålow tack¼, which can be used to back materials and releases well after cutting. This ålow tack¼ masking tape is available through sign writer supplies and is called „Application Tape¾. SLIDE 8: Leather-hard teapot with stencils made from newspaper stuck down on „Application Tape¾. These plotter-cut stencils were made by scanning tea leaves into the computer then selecting the tea leaf outlines. SLIDE 9: Two teapots with Darjeeling tea pattern. All types of papers and thin card cut well. One of the easiest and cheapest to use are wall papers including the lining wall papers which are available in various thicknesses or weights. I have also been successful in cutting thin rubber sheeting provided it is less than 1mm thick. One rubber that is made specifically for the plotter-cutter is sandblasting stencil. There are various types and thicknesses of sandblasting stencils. They are sticky backed and come with an acetate backing. The vinyls used by sign writers also make good stencils for slip resist on clay and can be washed and re-used, which is an advantage over paper stencils. One other drawback of plotter-cutting paper or card is that these materials blunt the scalpel blades more quickly than the plastic vinyls and rubber. Polythene and other plastic sheeting cut well, and most recently I have found that grease proof paper, normally used in baking, also plotter-cuts into excellent stencils. These have the advantage of peeling away from the backing sheet with ease. The polythene stencils can be washed and re-used, but can buckle when applied to curved surfaces. The grease proof paper stencils are thin enough to fit a curved form as they can be stretched slightly when wet. SLIDE 10: Ginger Jar SLIDE 11: Detail of Ginger Jar SLIDE 12: Plotter-cut stencils of fresh stem ginger scanned into the computer then plotter-cut, made from lining wall paper SLIDE 13: Black commercial rubber and white „Plastazote¾ rubber stencils Choosing Appropriate Technologies 2.) For Forms I looked for a mechanised making process which would enable non-circular forms to be made. I decided that it was essential to find a mechanised process which has the potential to allow interventions during the making. The Ram Press I selected the hydraulic ram press as the ideal industrial means of production. This machine raises and lowers a metal plate which has the top mould, or ådie¼, attached. The bottom die is placed directly below the top die mould. These ådies¼ are not conventional plaster moulds. They have thick metal casings and are made from alpha plaster which has been made porous. When a model is being cast into a die mould, the metal ring is placed over the model, then chicken mesh is put into the die so that it hovers approximately one inch above the model. Hollow nylon tubing, called „purge pipe¾, is now threaded through a hole in the wall of the metal die and then carefully woven into the chicken mesh trying to prevent the tube from becoming closed off by sharp corners. When the alpha plaster is poured into the die it is checked for the rise in temperature as the plaster goes off. A compressed air hose is attached to the end of the purge pipe through the hole in the metal die. Compressed air is forced through the purge pipe and then into the plaster thereby making the alpha plaster porous. The porosity of the plaster enables plastic clay to be released from wet die moulds after pressing due to compressed air pushing through the moulds as part of the ram press cycle of making. SLIDE 14: In my studio at Chapter Arts Centre, Cardiff - 8 cu. foot electric kiln on the left and my Simkin & Son Ram Press on the right. SLIDE 15: Metal die ring over model with chicken wire suspended above the model and nylon åpurge pipe¼ being woven into the chicken wire. The ram press cycle Place plastic clay into the bottom die mould; press the start button; a safety guard screen comes down; the top die is lowered down and presses the plastic clay into the mould; compressed air is pumped through the wet bottom die , pushing the clay off of the bottom mould and it then is stuck to the top mould; the top plate with the upper die mould with the plastic clay stuck to it now moves up, as does the guard screen; the operator places a board under the top die and steps on a foot pedal which sends compressed air through the top die mould which releases the plastic clay from the top mould and it drops onto the board. SLIDE 16: Clay dish stuck to upper die mould, ready to be removed with compressed air onto a ware board. What ram press to use I had visited manufacturers with ram presses and had considered trying to work from one of these sites. Wedgwood, Spode, Wades in Stoke-on-Trent, plus a more local maker, Canon Hill Pottery just 5 miles from Cardiff were all possibilities. There would have been a charge to cover time on the ram press, clay used, plus bisque firing. I intended to glaze and glaze fire from my own studio. At first this option was very appealing, but I knew that I worked best within my own work space without tight time pressures and I was also concerned by the cost. My second mortgage was put to good use as I managed to track down a second hand ram press. It was installed and set up in May 1999 when I also produced my first die moulds of my first dinner plate model. SLIDE 17: Ram pressed plate from my first model with 1 mm. rubber plotter-cut stencils of broccoli stem pattern. Having my own machine was daunting at first, but it has given a much greater freedom than I would have had leasing a ram press. This freedom has already enabled me to explore adaptations within the normal ram press cycle. One of the most useful adaptations came from swapping the compressed air hoses from the top and bottom dies. This enables multiple pressings of the same piece before it is removed from the die moulds. With two pressings rather than one, each ram pressed piece can be given individual surface detail. Of course you could put the details on the original model, including using the plotter-cut stencil shapes glued to the model. Each ram pressed piece would then be identical, as in industry, but I am interested in exploring the potential for the ram press to be used in a studio setting, producing one off or limited series pieces. COMBINING THE PLOTTER-CUTTER and THE RAM PRESS The combining of the plotter-cut stencils and the ram press has become the focus of my research. These mechanised technologies work extremely well together. By multiple pressing of the same piece, plotter cut stencils can be added during the making process. This enables the otherwise identical ram pressed pots to be individual one-offs or of a limited series. Both the top and bottom surfaces can have surface markings, with the thicker stencils giving deeper embossed markings. SLIDE 18: top of ram pressed plate with plotter-cut stencil. SLIDE 19: base of ram pressed plate with plotter-cut stencil The ram press cycle for multiple pressing with stencils or other material is as follows: switch the compressed air hose from the top die to the bottom die and vica versa; place stencil or other material in the bottom die for the base of the pot; place a slab of clay over this taking care not to move the stencil out of place; press the start button; the safety screen comes down followed by the top platten which presses the clay in between the moulds; compressed air is then automatically pumped through the top die mould which releases the clay; the top die mould is then raised up along with the safety screen; the clay remains in the bottom die mould; now switch the compressed air hoses back; place stencil or other material on the upper surface of the clay shape in the bottom die; now press the start button for the second pressing; the safety guard comes down followed by the top die mould which presses into the clay and stencils; compresses air automatically pumps through the bottom die which pushes the clay off the bottom die mould so that it is stuck to the top die mould; the safety screen and the top die mould rises with the clay shape stuck to it; place a ware board under the clay shape stuck to the top die mould; then, by standing on a foot pedal, compressed air is pumped through the top die to push the wet clay shape off the mould onto the ware board to remove the pot from the ram press. The stencils or other material have been pressed into the surface of the clay shape. SLIDE 20: clay slab placed on top of plotter-cut stencils in the bottom die mould. Removing the stencil material from the clay. The stencils can be used as a slip resist, or can be removed leaving plain embossed pattern work. Some of the plastic and rubber stencils however have not removed well from the clay after ram pressing, pulling away some of the clay surface. A light application of silicone spray, as used by upholsterers, applied onto the stencil prior to use has prevented sticking. One unexpected finding is that a more porous surface on the stencil releases from the clay better than a non porous surface. For example, silicone rubber sticks to the clay after ram pressing, whereas expanded foam rubber releases without sticking. One expanded foam rubber I use is called „Plastazote¾. It is a vulcanised rubber,which means that it has been subjected to heat and sulphur, leaving the rubber surface more porous. Ceramic colour on the plotter-cut stencils I have been exploring ways in which the plotter-cut stencils could not only be used to emboss pattern into the ram pressed pots, or become slip resist stencils, but also could add colour directly onto the clay surface. At the beginning of my research I asked Peter Castle, course director of the Ceramic M.A. at the Centre for Ceramic research, Cardiff, a question, „Is there some way of printing flat colour onto paper that can then be cut into stencil shapes, which could then be placed face down onto a wet clay surface, and subsequently have the colour remain on the clay when the backing paper is removed?¾ We discussed a variety of options, including the simplest which involved taking transfer paper and screen printing the ceramic colour on top, then NOT cover coating it as you would do normally for transfer printing. Peter happened to have some screen printed enamel fish shapes on transfer paper which had not been cover coated. The very first test with these fish shapes worked well. By wetting the paper first then placing it face down onto the plastic clay, the colour was released onto the clay and remained there after the backing paper was peeled away. Such positive results gained so quickly prove that the most valuable part of having a research post is the contact with other makers. Transfer paper with ceramic colour on top can easily be cut into a stencil on the plotter-cutter. SLIDE 21: Transfer paper with enamel mixed in acrylic medium rolled onto the surface then plotter-cut when dry into runner bean shaped stencils. Fresh runner beans were scanned into the computer and the outlines selected to make the stencil shapes. SLIDE 22: Detail of ram pressed plate showing the blue enamel colour from the plotter-cut runner beans. SLIDE 23: Enamel printed transfer paper, ram pressed into the plate surface, now the backing paper is being removed leaving the blue enamel from the surface of the transfer paper stuck to the clay. My first trials used oil based printing medium mixed with dry powdered cobalt slip on transfer paper, but the oil based medium did not shrink with the clay as the clay dried. After consulting once again with Peter, he suggested trying a water based acrylic medium. This mixture was more successful, and has the advantage of being water based. Rather than screen printing, to save time I applied the colour directly onto the transfer paper using a roller. I then realised that the colour could be applied to the transfer paper in any way I chose. In addition to flat colour, traditional slip techniques of marbling and feathering have also worked well and I will continue to explore their use. VEGETABLES The vegetable shaped stencils made on the plotter-cutter came from actual vegetables scanned into the computer. After scanning, the image of the vegetable is worked on to produce black & white outlines suitable for the plotter-cutter. The broccoli stem slices for example were scanned into the computer, turned into black and white images using Photoshop, then plotter cut out of 1 mm thick sandblasting rubber and used to make embossed pattern on the ram pressed form. Some of these rubber stencils were glued together to make triple layered stencils, giving triple layered embossed pattern. SLIDE 24: Slip decorated ram pressed plate with plotter-cut broccoli stem pattern rubber stencils. SLIDE 25: Base of ram pressed plate with triple layer rubber stencils of broccoli pattern. While I was slicing the broccoli stem I realised that the actual pieces of broccoli themselves could be ram pressed into the clay. Water filled, firm vegetables, like broccoli, celery, onion etc ram pressed perfectly into the clay. One added bonus is that the vegetables dry and shrink faster than the clay does. When left out overnight, by the next day the vegetable shapes have dried and shrunk away from the clay and are easily removed , leaving behind perfect impressions of their surface and form. SLIDE 26: 3mm thick broccoli stem slices ram pressed into the surface of a plate. SLIDE 27: Glazed porcelain ram pressed plate with celery slices pressed into the surface. The glaze has pooled into the celery shaped depressions and these are translucent when the plate is held in light. Using fruits and vegetables for pattern work furthers my long standing interest in making tableware which is related to the food for which it is intended. Microscopes Just prior to applying for the research post in 1998 I received an award to buy a stereoscopic microscope. Along with the plotter-cutter, computer and ram press, I also used my second mortgage to invest in a high magnification microscope. I have used these microscopes to gather visual information from vegetables and fruits. The microscopes both have camera attachments which enable photographs to be taken of what ever image is being examined on the microscope. The 35mm slides taken of the microscopic imagery can be scanned into the computer, or can be sent off to a photographic processing company to have them put onto a CD. Once the images are on the computer they can be edited, added to and changed to suit the intended use. For example, the image could be turned into a black & white image, the outlines selected and then used to make a plotter-cut stencil. SLIDE 28: Cells from a broccoli stem photographed through my microscope. SLIDE 29: The image from slide 29 was simplified on the computer, outlines selected and used to plotter-cut vinyl stencils for use with the ram press. Conclusion I set out to identify and work with industrial technologies for tableware production which would enable an exploration of a crossover, or interface between industrial and hand made tableware. SLIDE 30: Ram pressed plate with plotter-cut broccoli pattern stencil. SLIDE 31: Detail of slide 31 I am hoping to combine the individuality, freshness and attention to detail possible with hand made tableware, with the making possibilities and efficiencies of industrially produced wares. My strategy for achieving this is to make individual interventions during the making of what would otherwise be identical pieces. This is a process of trial and error, with each step being recorded and evaluated which then informs the planning of the next set of investigations. This rational approach is balanced by giving equal importance to intuitive working practice, thereby allowing the sense of fun and curiosity generated by this new work to produce the unexpected. SLIDE 32: Ram pressed plate with runner bean plotter-cut stencils. SLIDE 33: Ram pressed plate with celery plotter-cut stencils. SLIDE 34: Detail of ram pressed plate with ådirect release¼ enamel colour from plotter cut stencils of runner bean stars pattern. SLIDE 5: Six ram pressed plates. I will continue to make a wide range of wheel thrown and turned tableware, with the ram press being used predominantly to make non-circular dinner plates and other flatwares.