© Folens 2009 Learning objectives/aims All students: must be able to understand the factors that make a fabric ‘fit for purpose’. Most students: should be able to use simple fabric tests to identify the properties of fabrics. Fabric properties
© Folens 2009 Fabric properties and characteristics When we look at fabrics and describe how they look and feel we are looking at the fabrics’ properties and characteristics. You will need to know about the physical characteristics and properties of a range of fibres and fabrics. This refers to how they feel and behave in use. You will also need to know about the aesthetic characteristics and properties of a range of fibres and fabrics. This refers to their appearance.
© Folens 2009 Examples of fabric properties Creasing Fraying Absorbency Strength Elasticity Flammability Wearability Durability Warmth After care Itchy Fluffy Comfort Stain resistance Pilling Smooth Abrasion Static Snagging Shrinking Colourfast Safety
© Folens 2009 Fitness for purpose (1) Designers must choose fabrics that are ‘fit for purpose’. In other words the fabrics must be suitable for the job they have been chosen for. To do this they have to consider the properties of the fabrics and match these to the properties of the product being made, e.g. if they are designing a raincoat the fabric will need to be water repellent.
© Folens 2009 Fitness for purpose (2) When choosing fabrics a designer needs to know: What the intended product will be. When, where and how it will be used. Who the target market is. The price bracket the product will fit into.
© Folens 2009 Testing fabrics Designers will compare different fabrics to find the one that is most suitable for the product they are making. They will also test and evaluate fabrics to make sure they have the right properties for the product being made. There is a wide range of tests that can be done on fabrics to identify their properties. Look at the worksheet ‘Fabric testing’ for more details.
© Folens 2009 Fabric testing in industry (1) British Standard Institute (BSI) fabric tests are often used in industry. These are a set of standard procedures for testing fabrics that companies can buy. Using a set of standard tests helps make sure all tests are carried out fairly and to the same standard each time. Multi-fibre strips are made from strips of different fibres. In industry they are attached to fabrics being tested and the fibre strips show changes when washed. This example shows a fabric that has lost its colour when washed. Notice how only some of the fibres have been stained. Fabric testing machines are used in industry and these help ensure accuracy. You can see some of these machines on the next few slides. Look at the BSI website for more information on fabric testing:
© Folens 2009 Fabric testing in industry (2) Abrasion testing Fabric is stretched across metal plates and rubbed in circular motions. The machine counts the number of rubs it takes for the fabric to go into holes.
© Folens 2009 Snag testing Sharp edges are dragged across the fabric to see if the surface threads are pulled loose. Fabric testing in industry (3)
© Folens 2009 Pilling (bobbling) testing Fabric is wrapped around cones and put into the boxes which then rotate causing the cones to tumble and rub against each other. Fabric testing in industry (5)
© Folens 2009 Tensometer Fabric is clamped into the machine which slowly moves the clamps apart and measures the pressure that can be applied before the fabric rips. When testing the strength of a seam this is called ‘seam slippage’. Fabric testing in industry (4)