Plain weave derivatives
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The document discusses various weaving techniques in textile engineering, focusing on warp rib and weft rib weaves, including their characteristics and applications. Additionally, it describes haircord and hopsack weaves, emphasizing their structural differences and advantages in fabric strength and appearance. Overall, the text highlights the complexity and functionality of different weave types in fabric design.
Plain weave derivatives
- 1. Fabric Structure and Design Azmir Latif, MSc in Textile Engineering 25 Fig.3.1 Warp Rib Weaves Plain Weave Derivatives RIBS A weave in which either owing to the interlacing or to the yarns used, warp or weft is the stronger or remains comparatively straight, while the other material does all the bending. 1 Warp Rib Weaves Warp rib weaves are made by running two or more picks together, a shown in Figure3.1 This produces pronounced weft-way ribs, the surface of which consists of warp threads. The rib effect is emphasized by the use of a greater number of ends than picks and the insertion of coarser weft yarns. Consequently, the picks tend to lie rather straight with the ends bending round them, thus producing a warp rib structure in which the warp is mainly visible. The advantage of introducing two free weft yarns instead of one coarse yarn is that a broad rib is achieved without greatly increasing the thickness or weight of the cloth. Since some confusion can arise in the terminology used, it is worthwhile drawing attention particularly to the fact that 'warp rib' weaves produce ribs running weft-way. WARP RIB. Rib effects result from extending the plain weave vertically. The weft is thicker causing the warp to bend and form a warp surface rib running from selvedge to selvedge. Warp ribs are woven with a high warp sett, in which the ends cover the weft almost entirely. The ribs can be emphasized even more strongly by use of alternate slack and tight ends and thick and fine picks. 2 Weft Rib Weaves Weft rib weaves are the opposite to warp rib weaves, as shown in Figure 3.2. The weft is prominent on both sides of the cloths, which has warp-way ribs or cords running lengthwise. Such weaves are not commonly used in fabrics for clothing because it is uneconomic in weaving to insert the large number of picks which AZMIR
- 2. Fabric Structure and Design Azmir Latif, MSc in Textile Engineering 26 Fig.3.2 Weft Rib Weaves are required. It may be noted that in Oxford shirting the two ends weave as one (and help to increase the tearing strength of the fabric), but the other details of fabric construction, such as threads per centimeter and yarn count, are not designed to produce or emphasize a rib effect. This type of fabric is sometimes referred to as a double-end plain. WEFT RIB. Rib effects result from extending the plain weave horizontally. The warp is thicker forming a weft surface rib running lengthways up the piece. Weft ribs are woven with a high number of picks and a low number of ends. 3 Haircord Haircord is often used for cotton dress fabric, especially in children's wear. The weave is characterized by the use of a plain weave in which pairs offends weave as one and alternate with single ends, as shown in Figure 3.5.The cloth has a fine warp-way rib caused by the pairs of ends. 4 Hopsack, mat or Basket Weaves HOPSACK WEAVES Hopsack weaves (synonym 'matt') are produced as 2/2 or 3/3 hopsack, for example. See Figures 3.3. It will be seen that two or more ends and two or more picks weave as one, giving a fabric with a smooth surface but with a greatly enlarged coarse plain-weave structure. Fabrics bearing the name of this weave are commonly made from worsted yarns. If two fabrics of otherwise similar construction are woven as a plain and a 2/2 hopsack, it will be found that because of its fewer intersections the hopsack weave will tend to be less stiff. In addition, when a 2/2 hopsack fabric is torn, the threads will break in pairs and the cloth will, therefore, have a greater resistance to tearing than a comparable plain cloth, in which the threads break one at a time. The ordinary “HOPSACK” weaves are enlargements of plain weave with two or more threads and picks interlacing alike. On account of the loose method in which the threads interlace, large designs are only employed in fine fabrics. It is possible to obtain well interlaced effects in coarser fabrics by combining hopsacks with warp and weft ribs.
- 3. Fabric Structure and Design Azmir Latif, MSc in Textile Engineering 27 Fig.3.3 Hopsack Weaves The ends which work together tend to twist or roll round each other as the cloth in woven. The twisting of the ends can be prevented by tending them in such a manner that those which work alike are separated by the wires of the reed. BASKET WEAVES Under this head are included the weaves as shown in Figure 3.4 in which perpendicular and horizontal breaks or recesses occur at intervals where adjacent warp and weft threads are stitched in opposite order. Fig. 3.4 Basket Weaves Fig. 3.5 Haircord and Twilled Hopsack