Knitted fabrics are made from interlocking loops of yarn. There are two main types of knitting: WEFT KNITS WARP KNITS In weft knitting the loops of yarn are linked across the width of the fabric. In warp knitting the loops are linked in a vertical direction. To recap on what we know about fabrics – they can be woven, non-woven or knitted. Today, we are going to learn a little bit more about knitted fabrics. Knitted fabrics are made from interlocking loops of yarn. Depending on the type of knit construction, this will either be a single yarn, or several yarns. If the loops are broken, the fabric will easily come apart. There are 2 types of knitted fabric: WARP & WEFT. Warp knitting machine

Weft Knitting Weft knitting is made using a single yarn. It can be made by hand knitting or by machines. Characteristics of weft knits: The fabric has high elasticity and stretch. The loops of yarn trap air which retains body heat to keep us warm. The right and wrong sides of the fabric look different. the fabrics can lose shape easily. Creases fall out easily. The fabric can unravel and ladder easily. Weft knitted fabrics curl up at the edges when they are cut. Weft knitting is the type we generally think of as a knitted fabric. It can be be very heavy gauge (thick & chunky) or very fine gauge (used for T-shirts & underwear). Weft knitting uses a single yarn & the loops are linked across the width of the fabric. It can be done by hand or by machine. This type of knitting can unravel, & will ladder if a stitch is dropped, or the yarn is broken (think of what happens to your tights if you snag or catch them on something). I’m going to show you some clips of how the knitting is formed, & then we’ll have a go at producing a bit of our own.

Weft Knitting Weft knitting machines being used in industry: http://www.youtube.com/watch?v=B4qzdAdhKIo What this looks like in slow motion: http://www.youtube.com/watch?v=SUXk-EHKD_c&feature=related How to knit by hand: http://www.youtube.com/watch?v=4ViZRI6oPPg&feature=related In industry, warp knitting is made on huge computerised machines. These can be flat bed, V-Bed or circular machines. We’ll have a look at a clip of a flat bed machine. The 2nd clip is of a home-made knitting machine. Its much slower but it shows quite clearly the single yarn going across the bed of needles & the loops that form each stitch. It’s these stitches that give knitting its V-shapes. (If clip doesn’t work, put in ‘knitting machine – handmade’ into search engine on You Tube) The last clip is of hand knitting. Watch closely, as we’re going to have a go at knitting this stitch ourselves. It’s the most basic knitting stitch & is called the garter stitch.

Warp Knitted Fabrics In warp knitting the yarn loops vertically up the fabric and the process uses many yarns rather than one. The fabric does not unravel or ladder. It is an industrial process only. Warp knitting uses lots of different yarns which are looped together vertically as well as horizontally. The fabric doesn’t unravel when it is cut, so it won’t ladder. It is very fast to produce. The fabric is elastic but will still keep its shape. However, the machinery is very complicated, so the fabric can be expensive to produce. Warp knitting is used to make lace & nets (such as lace curtains) & a fabric called lock-knit which is used for bed sheets, furnishing fabrics, velour & swimwear. Characteristics of warp knits: The production system is fast so the fabrics are quick to make. The fabric is elastic but it can keep its shape. It can be cut and sewn easily as it lies flat when cut. It is mainly used with synthetic filament yarns.

Warp Knitting A warp knitting machine http://www.youtube.com/watch?v=xrSU2XfkAdg&feature=related Making a narrow lace trim http://www.youtube.com/watch?v=Wpx5Cubq7oo&feature=related Warp knitting machines can be used to make lace which is currently very on-trend & fashionable. This 1st clip shows a modern warp knitting machine & you can see that there are many yarns being knitted & looped together (if clip doesn’t work, click on the thumbnail on the right that is called 1.m2ts) The 2nd clip shows an older piece of machinery using many small bobbins of yarn to make narrow lace trims. (if clip doesn’t work, click on thumbnail entitled lace making machine, then on another thumbnail for same thing but a darker image, as this is a better clip).

Uses of Knitted Fabrics Weft Knits T-shirts Jumpers Cardigans Sweatshirt fabrics Warp Knits Net curtains Swimwear Terry towelling fabrics Patterned tights Lace fabrics So finally, a quick re-cap on some of the products that are made from knitted fabrics. If there is time, & the plexi-scope is working, show the knitted construction under the microscope.