#4 Fabric Videos-Bethany Huizenga-Snyder

 Blog 4 Fabric videos 

WEAVES AND KNITS 

Weaving- 

weaving has been around for a long time. The systems are still the same, the machines have just become faster. The machines have a warp and a weft yarn. The warp yarns are tight in the heddles, and they move up and down. Old looms have shuttles, but they now use rapiers which pass the yarn off on the middle. The rapiers can hold more yarn so that makes it faster. To create patterns weft presenter which feeds different color yarns to the rapier. For complex patterns, a jacquard attachment is needed. This is where each thread is moved up and down individually. The threading of a jacquard loom is so labor-intensive that they only load it once. Because of the invention of the machine looms textiles have become much cheaper. 

 

Denim Manufacturing-

weaving states with a sized yarn coming off of a loom beam coming off in a single layer. Then it goes over a tension bar and through drop wires which serve as stop motion detectors. Then the warp yarns pass through a heddle, this controls the raising and lowering of each yarn. Then it passes through a reed which maintains the spacing of the yarns and pushes the weft yarn into place tightening the weave. Then the weft yarn is run through the warp yarn and the fabric is rolled up. There are machines that can tie new yarn to the old yarn when it runs out.

Twill Weaving-

twill fabrics are characterized by the diagonal pattern on a cloth made by the rising of the warp yarns over the weft yarns. If the twill line moves from the lower left to the upper right it is considered a right-hand or a Z twill, and it if moves the other way it is considered a left-hand twill or an S twill. The angle of the twill is the result of the ratio of warp to weft yarns. The sizes of the yarns also affect the angle of the twill. A 45% angle is considered a normal twill. Twill weaves are designated by what is known as the counter the counter twill designates the order of weaving of the first end of the repeat. The simplest of twills is a 1x2 twill.  The appearance of the twill line can be accentuated or diminished by the direction of the yarn twist. The tension on the warp yarns can also have an effect on the height of the twill. Herringbone twills are created by doing a left-hand twill then a right-hand twill and so on. 

   

Jacquard weaving- 

Before the 1800s complex patterns had to be done by hand and that took a long time. In 1801 Joseph Jacquard invented a new loom attachment. It automated how patterns were woven. First, the design was copied onto a grided paper, and then workers translated the design into punch cards. The cards were stitched together in a continuous belt and fed into the loom. Holes in the cards control which treads are raised for weaving the pattern. This meant intricate patterns were now available to more people. 

 

KNITS-

Weft and Warp Knitting- knitting is defined as the intermeshing of yarn into loops to form a fabric. There are two systems for knitting, weft, and warp. Weft knitting is accomplished by loops formed in a horizontal manner by adjacent needles. The most common machine used for this is the circular machine. Regardless of the machine used, needles palace next to each other and knit one after another in sequence to produce one row of loops out of one yarn. Warp knitting is accomplished by forming loops in a vertical direction. with warp knitting, each individual loop is created from separate lengthwise yarns wound onto a beam. With these machines needles knit simultaneously across the width of the machine. 

 

FIRE

Fiber Identification by Burning- 

Cotton- burns, doesn’t melt, smells like burning paper or wood, residue: fine gray ash

Falx- burns, doesn’t melt, smells like burning paper or wood, residue: fine gray ash

Wool- burns, doesn’t melt, strongly smells of burning hair or feathers, stops burning when removed from the fire, residue: black hollow bead that can be crushed to black powder. 

Silk- burns, doesn’t melt, strongly smells of burning hair or feathers, the odor is not as strong as wool, stops burning when removed from the fire, residue: black hollow bead that can be crushed to black powder. 

Rayon- burns, doesn’t melt, smells like burning paper or wood, residue: fine gray ash

Synthetics (Nylon/Polyester/Acrylic): Ignites and burns quickly and can continue to burn after a flame is removed—exercise caution. Fiber may shrink from the flame, melt, and drip (DANGER) leaving a hard plastic-like bead. Burning these fabrics will produce black smoke and hazardous fumes. Nylon smells like plastic when burnt but can also produce a celery-like smell; Acrylics burn with a strong, acrid, chemical smell. Polyester smells slightly sweet, also with a chemical odor.

Polyester- shrinks from heat, melts, burns, can drip, smells chemical, sweet, residue: hard cream or black cored bead that cannot be crushed.

Nylon- shrinks from the heat, melts, can burn, smells a bit like celery, residue: hard cream or black cored bead that cannot be crushed.

Acrylic- shrinks from heat, melts, and burns, sputters when burning, acrid smell, residue: hard black bead that can be partially crushed.

Acetate- shrinks from heat, melts, and burns smells like burning cellulosic fibers (of burned wood, paper) with a bit of vinegar, residue: hard black bead that can be partially crushed.

Cellulose (Cotton/Linen/Hemp/Rayon/Bamboo): Ignites and burns quickly, may flare, and leaves a glowing ember after the flame is extinguished. Smoke is white or light colored and smells like burnt paper or leaves. Ash is light gray or white and very soft.

Protein (Silk/Wool, Cashmere, Alpaca, etc): Burns slowly and shrinks or curls away from the flame. Will not stay lit after the flame is removed. Very little smoke is produced but it smells like burnt hair (wool) or feathers (silk). Ash is a gritty powder or a dark brittle, easily crushable bead.

Synthetics (Nylon/Polyester/Acrylic): Ignites and burns quickly and can continue to burn after a flame is removed—exercise caution. Fiber may shrink from the flame, melt, and can drip (DANGER) leaving a hard plastic-like bead. Burning these fabrics will produce black smoke and hazardous fumes. Nylon smells like plastic when burnt but can also can produce a celery-like smell; Acrylics burn with a strong, acrid, chemical smell. Polyester smells slightly sweet, also with a chemical odor.

 

Tensile Strength Testing- 

To determine the strength of the fabric they put it on a machine that stretches it. They cut the piece of fabric to 50 mm wide. When the fabric breaks, they stop the test. The machine calculates the amount of force it too to break the fabric. On a standard test, they would repeat that 5 times in the warp direction and 5 times in the weft direction.

 

Abrasion Testing-

In this video, we watched them do a variety of tests on fabrics. The first test they did was drawing on it with a pen, it drew on it in a circular motion. The next test they did was rubbing two of the same fabrics together in a circular motion. Then they rubbed two different materials together in a circular motion