Section 5: DIAGONALS Diagonals is a turning-defined technique in which all tablets are threaded with the same arrangement of colours. On four-holed tablets it is called Egyptian diagonals. Plate 5-1 shows some colour charts that can be used with this technique. Typically three colours are used but more are possible. In Plate 5.1(b.), one of these colour charts is selected: white in A and B, pink in C and D, blue in E and F. The tablets are then rotated into the starting positions shown, which is the flat twill angle. Later the steep angles will be explored. By turning all backward turns the textile illustrated will be woven, with Z- diagonals and colours repeating in the same sequence as in the colour chart. This pattern is the background or fundamental weave for this technique. This colour chart, threading and starting position set-up is assumed for the remainder of the study of the flat twill version of this technique. In Plate 5-2, the squared area (a.) is a turning chart. Each column represents a tablet, and each row represents a shed for weft insertion. When the entry for a tablet is a white square, it indicates that the tablet should be turned backward. If the entry is a gray square then the tablet should be turned forward. Notice that for the first three rows of weaving all tablets are turning backwards. As a result, the fragment of textile that corresponds to those rows is the expected background weave. Designs are created on this background by an overlay that is made up of 3x3 gray squares. These squares are shaded gray because they are regions of forward turns embedded in our grid of backward turns. In order to obtain predictable results with this approach, gray squares should be fitted between the red and blue grid lines drawn on the chart. Failure to do that will affect the colour continuity of the maze. The 3x3 squares can be grouped into larger shapes such as crosses and stairs. These squares create symmetry on each of their four edges. Looking at the shapes that are outlined in the simulated weaving (b.), we can see that symmetry over the horizontal edges is perfect in both line and colour. Over the vertical edges the lines reflect but the colour continuity breaks. The blue Six-Holed Tablet Weaving, Section 5 1
diagonals are continuous, but the other two colours interchange at these edges. Plate 5-3 shows how to reproduce a design from a woven band or from a sketch. This process is similar to the way we made the Ram s Horn pattern. Start by shading in gray the areas that have S diagonals on the original, then approximate these shapes using 3x3 squares. Overlay these gray squares onto the white grid. These patterns produce the weavings simulated on the right. Plate 5-4 shows how easy it is to take a regularly repeating image and use it as the basis of a design. On the top is a design derived from the key band that we considered earlier, only now the key is drawn in 3x3 blocks rather than individual squares. It produces the rather complex looking weaving to the right. Below is a design based on large triangles of each type of turn. Plate 5-5 shows some examples of designs derived from weaving drafts. So far we ve dealt with the flatter of the two twills possible, obtained by arranging tablets in the starting position [0,5,4,3,2,1], repeated for the width of the weaving. Now let s turn our attention to the steeper twill. Recall that the steep twill is woven by arranging the starting positions of the tablets to be offset by two, so now the standard start position is [0,4,2], repeated for the width of the weaving. Two simulated weaves are shown in Plate 5-6, both woven from the same pattern (a.). Simulation (b.) is the flat twill that we have already examined, and (c.) is the steep twill. The first thing we notice is the steeper incline of the lines. A close examination of the portions outlined shows that the striping is not just steeper, but narrower too, since the outlines now contain twice as many stripes. A more subtle effect is illustrated in the lower section. Since the darkened cells on the pattern follow a 45-degree angle, that section woven on the flat twill creates lines that are approximately perpendicular to the stripes in the ground weave, with a constant edge where the two meet. But on the steep twill this is not the case, and the edge no longer follows a coloured stripe. Six-Holed Tablet Weaving, Section 5 2
To obtain an edge at which the coloured stripes meet in a regular way, the steps need to be changed from 3x3 cells, shown again in Plate 5-7 (a.), to 3x6 cell units, as shown in (b.). Using the steep diagonal with designs in which the turn reversals are rectangular blocks produces taller, slimmer versions if the imagery. The turning chart (a.) in Plate 5-8 results in (b.) on the flat twill, and (c.) on the steep twill. Similarly, chart 5-8 (d.) produces (e.) on the flat twill and (f.) on the steep twill. Plate 5-9 shows the designs discussed before that are derived from drawdowns. The top one already has 3x6 units and therefore weaves into a pleasing design on the steep diagonal without any changes. For the lower one, the pattern has been modified so that the steps are 3x6 rather than the 3x3 that we had for the flat diagonal, and as expected this produces a weave with solid lines at a 60-degree angle. Six-Holed Tablet Weaving, Section 5 3
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