From speaking to the weavers as they work, and from direct observation of the looms in action, I am beginning to comprehend the methods and mechanisms used to create patterns and different structures in woven cloth. Before Joseph Marie Jacquard invented the punch card system in 1804, the ‘draw-boy’ would perform the task of lifting the threads in order atop of the loom for each stage of the weaving process, while the weaver passed the shuttle back and forth at the front. Jacquard’s invention of the punch card mechanism automated the design of the weave on the loom. Diverse, interlaced thread structures can be realised by changing the instructions on the punch card. First a peg plan is made and then this information is transposed onto a punch card.
Zoe from The Bristol Weaving Mill kindly gave me some punch cards from her college days, such lovely objects in their own right, made from dense card and laced together with pastel coloured threads. She told me that any notation shown in black on a threading or peg plan is ‘active’ and so is an instruction to lift a shaft. Throughout the design studio and the mill there are notebooks, print outs, reference books and computer screens with checkerboard like data containing countless weave structures. The warp threads that pass from the front to the back of the loom are called ends. The weft threads which the shuttle passes from side to side are called picks.
There is digital software that feeds the equivalent punch card instruction to the majority of the hand looms and the Jacquard loom at Dash & Miller. While at The Bristol Weaving Mill downstairs, there is a large industrial loom which works off plastic punch cards. From a prepared print out of the peg plan, the weavers punch the data into acetate sheets by hand, line by line, on a punch-card machine. The machine resembles a typewriter and there is a choice of up to 28 numbers to punch per line. Depending on the complexity of the weave and whether it alters as part of the design, the punch cards can vary significantly in length, from short tubes to very long looped sheets. When the punch card has been cross checked for errors and corrected, it can then be read by the loom. A metal plate called a dobby head on one side of the rapier weaving loom has a row of raised pins. By this mechanism, the card is read, one line at a time. If a hole is found, the corresponding shaft is lifted. This creates the ‘shed’, the space between the threads for the rapier (in place of the shuttle on a hand loom) to pass through.
In some instances, different threads are used in combination for the warp setup. If two materials are used, such as linen and cotton, these may be affected by temperature and humidity. This can cause problems with the tension of the warps, or can mean that one material weaves better or worse during the summer or winter. Changes in the atmosphere can mean that the warp ends may need to be tightened or adjusted as time goes on, otherwise the yarn may have a tendency to break. Sometimes the yarn is sprayed with water to prevent it from becoming brittle. Dressmaking pins are always to hand, and are used to tie on new warps when they have snapped under tension or friction.
Upstairs at Dash & Miller it is fascinating to observe the sensibilities of individual weavers coming through in their samples. I ask the women if they have a clear vision of what each fabric will look like once it’s woven and they each have a different way to describe what they see in their minds eye. Their depth of experience and the pace of making means that there is an intuitive vibrancy to the work produced. Once a piece is completed, the fabric is cut off, washed, dried and then trimmed. Certain fabrics are finished on a heat press, some may be brushed or whole areas of threads may be snipped to create a tufted or distressed surface. I sit at one of the Dobby hand looms and am surprised when the seat rocks backwards and forwards as my feet move on the treadles. On a wide loom the shuttle is not so easy to pass through the shed in one go, but it is wonderful feeling to be a part of the machine. I only wish that I too could be an expert, like all of the women here.