T.J. Mahar, R.C. Dhingra and R. Postle
The mechanical properties of fabric longitudinal extension and compression, shear and bending have an important influence on the performance of fabrics during tailoring and also…
Abstract
The mechanical properties of fabric longitudinal extension and compression, shear and bending have an important influence on the performance of fabrics during tailoring and also on the performance of garments during use. Fabrics are overfed or underfed in tailoring during the sewing operations in such a way that longitudinal compression and extension are allowed in the fabric plane in order to produce the three‐dimensional shape or fullness of the garment. Fabric buckling or puckering at the seams should not occur, or if it does, should be removed during subsequent steam pressing operations. An experiment is described to measure the maximum limit of overfeeding that is possible during seaming without the subsequent formation of seam puckers. The relationships are studied between the maximum degree of overfeed, the bias angle between the feed direction and the fabric warp or weft, fibre type and fabric mechanical properties, especially fabric formability defined as the product of fabric bending rigidity and fabric longitudinal compressibility. When fabrics are extended or compressed longitudinally at a bias angle to the warp or weft direction during seaming in order to produce garment fullness, the warp and weft threads are rotated relative to each other in such a way that a local shear deformation is applied to the fabric adjacent to the seam‐line. Measurements are reported of the variations in the local shear angle along the shoulder seam‐line of a men's jacket and the measured values are related to the high degree of overfeed required in the bias direction in this area of the garment. Finally, hygral expansion measurements for wool fabrics and yarns unravelled from the fabrics are measured and compared for six different wool fabrics.
Details
Keywords
T.J. Mahar, I. Ajiki, R.C. Dhingra and R. Postle
In Parts 1 and 2 of this series of papers, we have investigated the important mechanical and physical properties of fabrics which determine their performance during tailoring…
Abstract
In Parts 1 and 2 of this series of papers, we have investigated the important mechanical and physical properties of fabrics which determine their performance during tailoring especially fabric tensile, shear, bending and dimensional properties. The conditions for structural balance of seams has been quantitatively evaluated as well as the relationship between the degree of fabric overfeed during sewing and the natural curvature or curling couple of the seamed fabric assembly. Fabric forming and draping behaviour is strongly dependent on fabric bending and the fabric membrane properties of extension, longitudinal compression and shearing in the fabric plane. In this paper, the influence of these basic fabric mechanical properties on subjectively assessed garment appearance is also studied. These mechanical properties can be used to distinguish between fabrics which make up into suits of good and poor appearance. The investigation of the bending properties of overfed fabrics has established an empirical relationship between the level of fabric overfeed and the natural curvature of the overfed seamed fabric composite for three different fabric configurations.
Details
Keywords
T.J. Mahar, I. Ajiki and R. Postle
In Part 1 of this series of papers, we investigated the importance of fabric overfeed in the sewing operations during tailoring. It was also shown how fabric bending rigidity…
Abstract
In Part 1 of this series of papers, we investigated the importance of fabric overfeed in the sewing operations during tailoring. It was also shown how fabric bending rigidity, formability, shear and hygral expansion are important in clothing manufacture. The present paper is concerned with the measurement and experimental study of seam balance, breaking elongation and bending properties of seams. The aim is to evaluate quantitatively the consumption of sewing thread and the relationship between the degree of fabric overfeed during sewing and the curvature of the seam in the garment. Balanced seams have much higher breaking elongation and more symmetrical bending properties than unbalanced seam structures. A natural curvature and curling couple result from fabric overfeed during sewing. The value of the curvature is time‐dependent because of fabric viscoelastic effect and also depends on the level of fabric overfeed, the tensile and longitudinal compressive module of the component fabrics and the structure of the seamed composite. The natural curvature of the seam may be derived quantitatively from the relative lengths of overfeed fabrics using a modified theory for a bimetallic themostatic strip.
Details
Keywords
U. Biglia, A.F. Roczniok, C. Fassina and N.G. Ly
A simple measurement of fabric pressing performance as indicated by crease angle has been developed and applied to the prediction of appearance of wool and wool blend tailored…
Abstract
A simple measurement of fabric pressing performance as indicated by crease angle has been developed and applied to the prediction of appearance of wool and wool blend tailored jackets. Industrial and laboratory trials have measured by the FAST system to give an assessment of garment appearance of lightweight fabrics after they are pressed.
Details
Keywords
M.Y. Leung, T.Y. Lo, R.C. Dhingra and K.W. Yeung
This paper investigates the relationships between fabric formability (a fundamental measure of fabric tailorability), bias extension and shear resistance. The experimental…
Abstract
This paper investigates the relationships between fabric formability (a fundamental measure of fabric tailorability), bias extension and shear resistance. The experimental investigation has been performed on a range of thirty-one (fifteen pure wool, twelve wooVpolyester blends, one wooVrayon blend and three pure linen) suiting and trousering materials varying in mass per unit area from 125 to 258 g/m2. Low stress mechanical properties measurements of fabric bending, shear and tensile deformations were obtained using the KES (Kawabata Evaluation System) testers. Furthermore, the 45-degree bias extension behaviour of these fabrics was measured using an Instron extensometer. Following Spivak and Treloar's analysis [12], the bias load-extension and recovery curves were analysed to obtain equivalent shear stress/strain hysteresis curves. The two measures of shear rigidity, one obtained from the KES shear hysteresis curves and the other calculated from the bias extension tests, have been compared for the series of 31 fabrics. Relationships between fabric formability (defined as the product of tensile extensibility under low load and the bending rigidity) and its shear resistance are analysed. In addition, the work also covers the investigation on the relationships between fabric shear properties and formability in bias direction.
Details
Keywords
M.Y. Leung, T.Y. Lo, R.C. Dhingra and K.W Yeung
This paper investigates the relationships between fabric formability (a fundamental measure of fabric tailorability), bias extension and shear resistance. The experimental…
Abstract
This paper investigates the relationships between fabric formability (a fundamental measure of fabric tailorability), bias extension and shear resistance. The experimental investigation has been performed on a range of thirty-one (fifteen pure wool, twelve wool/polyester blends, one wool/rayon blend and three pure linen) suiting and trousering materials varying in mass per unit area from 125 to 258 g/m2. Low stress mechanical properties measurements of fabric bending, shear and tensile deformations were obtained using the KES (Kawabata Evaluation System) testers. Furthermore, the 45-degree bias extension behaviour of these fabrics was measured using an Instron extensometer. Following Spivak and Treloar's analysis [12], the bias load-extension and recovery curves were analysed to obtain equivalent shear stress/strain hysteresis curves. The two measures of shear rigidity, one obtained from the KES shear hysteresis curves and the other calculated from the bias extension tests, have been compared for the series of 31 fabrics. Relationships between fabric formability (defined as the product of tensile extensibility under low load and the bending rigidity) and its shear resistance are analysed. In addition, the work also covers the investigation on the relationships between fabric shear properties and formability in bias direction.
Details
Keywords
Mei-yi Leung, T.Y. Lo, R.C. Dhingra and K.W. Yeung
This paper investigates the relationships between the fabric crease performance, seam retention and the low stress mechanical and constructional properties for a series of…
Abstract
This paper investigates the relationships between the fabric crease performance, seam retention and the low stress mechanical and constructional properties for a series of thirty-one suiting and trousering materials. A newly developed test method (IWTO draft test method) and instrumentation for evaluating the fabric crease performance was used to compare with the commercial steam pressing (Hoffman pressing). This newly test method was further modified for examining the seam retention properties. It has been shown that seam retention properties are significantly related to the fabric crease performance and are not affected by the different testing methods used and grain direction. In fact, the low stress mechanical properties of fabrics were not significantly related to either fabric crease performance and seam retention properties.
Details
Keywords
G. Wang, R. Postle, D.G. Phillips and W. Zhang
The press performance of a range of wool and wool blend fabrics has been investigated with the aid of a temperature adjustable hand steam iron, a domestic ironing board and a…
Abstract
The press performance of a range of wool and wool blend fabrics has been investigated with the aid of a temperature adjustable hand steam iron, a domestic ironing board and a thermocouple digital temperature display.It was found that for a press duration of 10 seconds, the fabric crease angle is reduced with the increasing press temperature. The sharpest reduction in crease angle was found in the temperature range of 80°C to 120°C for all fabrics tested.At 100°C iron temperature, the fabric crease angle was reduced with increasing press duration until 20 seconds for wool fabrics and until 30 seconds for wool blend fabrics.The initial regain, or in other words, the relative humidity of the ambient atmosphere used to precondition the samples, has an important influence on the press performance. It was also found that the fabric crease recovery was greater for increasing ambient relative humidity.The fabric regain was greatly reduced during the first 10 seconds pressing time with further very slow reduction in fabric regain until 80 seconds pressing time. The regain in the upper layer of the fabric specimen was always lower than that in the lower layer.
Details
Keywords
The continuing development of the textile and clothing manufacturing industries depends in no small measure on the successful implementation of reliable objective methods for the…
Abstract
The continuing development of the textile and clothing manufacturing industries depends in no small measure on the successful implementation of reliable objective methods for the specification, prediction and control of fabric quality and performance attributes. In the last decade, we have seen several notable examples of fabric design and development, and production and quality control in textile processing and clothing manufacture in terms of fabric objective measurement technology. The quality and performance characteristics of fabrics are related to their low stress mechanical, surface and dimensional properties. The experimental errors involved in the measurement of these properties are known to be much smaller than the errors involved in subjective assessment of fabric quality attributes, especially those made by individual judges. We may define the concept of fabric objective measurement as a necessary and sufficient set of instrumentally measurable parameters which are required to specify the fabric quality, tailorability and clothing performance. In this way, fabric objective measurement technology provides a “fingerprint” of the fabric quality, tailorability and performance implying that any two fabrics will generally differ at least to some extent in their objectively measurable characteristics. Fabric objective measurement technology therefore provides the key for scientific and engineering principles to be used for fabric specification and design as well as process control. The most important consequence of the introduction of fabric objective measurement technology will be the promotion of technological communication between various sectors of the textile and clothing industry, research and development workers and all other sectors of industry (e.g. fibre producers, retailing, merchandising, machinery manufacturers) concerned with fibres, textiles and clothing.
Details
Keywords
Milanka D. Nikolic and Tatjana V. Mihailovic
The phenomenon of fabric deformation can be observed not only keeping in mind the type of material, the raw material, geometric and constructive parameters, but also the…
Abstract
The phenomenon of fabric deformation can be observed not only keeping in mind the type of material, the raw material, geometric and constructive parameters, but also the conditions which which material is exposed under action of tensile force (the size of force, time, velocity of acting and so on). Investigates the influence of the tensile force size on total deformation as well as the deformation components: elastic, viscoelastic and plastic. Reports an experiment conducted on clothing wool fabrics (18 different samples) which were exposed to various tensile forces (5, 10, 15, 20, 25, 30 and 35 per cent of breaking force) during 15 minutes. After this time limit had expired, their relaxation in a period of 24 hours was examined. From the diagrams of fabric relaxation (126 diagrams), determines deformation components and presents a summary using diagrams. On the basis of imposed analysis claims it can be stated that elastic deformation component predominates while no plastic deformation exists at lower values of tensile force.