Best Textile Solution And Entertainment

* EXCLUSIVE* free best online income site

2012-01-16T12:53:00.005-08:00

Business Plan

Free Package

Subscription Fee	$0.00
Per Day Add	100
Earn Per Add	$0.01
Per Day Earn (Total)	$1.00
Monthly Earn	$30.00
Per Week Binary Income	$0.00
Sponsor Income	$0.00
Generation Income	$0.0

Free member get their addclicks after 7 days of their joining.A free member get addclicks for 100 days
Free member unable to make any kind of transaction before their upgrade.

Basic Packgae

Subscription Fee	$100
Per Day Add	$10
Earn Per Add	$0.15
Per Day Earn (total)	$1.5
Monthly Earn	$45
Binary Income(per week)	$500
Sponsor income	Unlimited
Generation income:	unlimited

Silver Package

Subscription Fee	$250
Per Day Add	25
Earn Per Add	$0.15
Per Day Earn (total)	$3.75
Monthly Earn	$112.5
Per week binary income	$800
Sponsor income	Unlimited
Generation income:	unlimited

Gold Package

Subscription Fee	$500
Per day add	50
Earn per Add	$0.15
Per day earn (total)	$7.5
Monthly Earn	$225
Per week binary income	$1000
Sponsor income	Unlimited
Generation income:	unlimited

Diamond Package

Subscription Fee	$1000
Per day add	10
Earn per Add	$0.15
Per day earn (total)	$16.5 (15+1.5)
Monthly Earn	$495
Per week binary income	$1500
Sponsor income	Unlimited
Generation income:	unlimited

Diamond member get 110 add daily folling the package.but they need to click only 10 add.Rest of the 100 click will be clicked by Free members.

It's easy to get started earning, simply click the button below!

Free Online Income at Home Without Investment From Onlineaddclick

Have You A Computer With Internet Connection?

Work Per Day 30 Minutes Any Time

From 1 Account 1 Dollar Bangladeshi 70 Taka.

From 3 Account 3 Dollars Bangladeshi 210 Taka.

Balance Withdraw (Western Union Money Transfer)

www.onlineaddclick.com
rupom1353 ...............placement ID ..... rupom1353 (position:left)

If You Really Interested Then Call Me Any Time
8801675535659
or mail me-
rupom_1353@ymail.com
or-
friendsandco2011@yahoo.com

Textile Manufacture

2010-04-05T03:06:00.000-07:00

Textile manufacture is a major industry. It is based in the conversion of three types of fibre into yarn, then fabric, then textiles. These are then fabricated into clothes or other artifacts. Cotton remains the most important natural fibre, so is treated in depth. There are many sources of fibre, and variable processes available at the spinning and fabric-forming stages coupled with the complexities of the finishing and colouration processes to the production of a wide ranges of products. There remains a large industry that uses hand techniques to achieve the same results.

Processing of Cotton:

Cotton is the world's most important natural fibre. In the year 2007, the global yield was 25 million tons from 35 million hectares cultivated in more than 50 countries.

There are five stages:

* Cultivating and Harvesting

* Preparatory Processes

* Spinning

* Weaving

* Finishing

Cultivating and harvesting:

Cotton is grown anywhere with long, hot dry summers with plenty of sunshine and low humidity. Indian cotton, gossypium arboreum, is finer but the staple is only suitable for hand processing. American cotton, gossypium hirsutum, produces the longer staple needed for machine production.[3] Planting is from September to mid November and the crop is harvested between March and May. The cotton bolls are harvested by stripper harvesters and spindle pickers, that remove the entire boll from the plant. The cotton boll is the seed pod of the cotton plant, attached to each of the thousands of seeds are fibres about 2.5 cm long.

Ginning:

The seed cotton goes in to a Cotton gin. The cotton gin separates the seeds and removes the "trash" (dirt, stems and leaves) from the fibre. In a saw gin, circular saws grab the fibre and pull it through a grating that is too narrow for the seeds to pass. A roller gin is used with longer staple cotton. Here a leather roller captures the cotton. A knife blade, set close to the roller, detaches the seeds by drawing them through teeth in circular saws and revolving brushes which clean them away.

The ginned cotton fibre, known as lint, is then compressed into bales which are about 1.5m tall and weigh almost 220 kg. Only 33% of the crop is usable lint. Commercial cotton is priced by quality, and that broadly relates to the average length of the staple, and the variety of the plant. Longer staple cotton ( 2 1/2 in to 1 1/4 in) is called Egyptian, medium staple ( 1 1/4 in to 3/4 in) is called American upland and short staple ( less than 3/4 in) is called Indian.

The cotton seed is pressed into a cooking oil. The husks and meal are processed into animal feed, and the stems into paper.

Issues:

Cotton is farmed intensively and uses large amounts of fertiliser and 25% of the worlds insecticide. Native Indian variety were rainwater fed, but modern hybrids used for the mills need irrigation, which spreads pests. The 5% of cotton bearing land in India uses 55% of all pesticides.[3] Before mechanisation, cotton was harvested manually and this unpleasant task was done by the lower castes, and in the United States by slaves of African origin.

Preparatory Processes- Preparation of yarn:

# inning, bale-making and transportation is done in the country of origin.

# Opening and cleaning:

Cotton mills get the cotton shipped to them in large, 500 pound bales. When the cotton comes out of a bale, it is all packed together and still contains vegetable matter. The bale is broken open using a machine with large spikes. It is called an Opener.In order to fluff up the cotton and remove the vegetable matter, the cotton is sent through a picker, or similar machines. A picker looks similar to the carding machine and the cotton gin, but is slightly different. The cotton is fed into the machine and gets beaten with a beater bar, to loosen it up. It is fed through various rollers, which serve to remove the vegetable matter. The cotton, aided by fans, then collects on a screen and gets fed through more rollers till it emerges as a continuous soft fleecy sheet, known as a lap.

Blending:

Mixing & Scutching:

Carding machine:

Carding: the fibres are separated and then assembled into a loose strand (sliver or tow) at the conclusion of this stage.

The cotton comes off of the picking machine in laps, and is then taken to carding machines. The carders line up the fibres nicely to make them easier to spin. The carding machine consists mainly of one big roller with smaller ones surrounding it. All of the rollers are covered in small teeth, and as the cotton progresses further on the teeth get finer (i.e. closer together). The cotton leaves the carding machine in the form of a sliver; a large rope of fibres.

Note: In a wider sense Carding can refer to these four processes: Willowing- loosening the fibres; Lapping- removing the dust to create a flat sheet or lap of cotton; Carding- combing the tangled lap into a thick rope of 1/2 in in diameter, a sliver; and Drawing- where a drawing frame combines 4 slivers into one- repeated for increased quality.

Combing is optional,but is used to remove the shorter fibres, creating a stronger yarn.

A Combing machine:

Drawing the fibres are straightened:

Several slivers are combined. Each sliver will have thin and thick spots, and by combining several slivers together a more consistent size can be reached. Since combining several slivers produces a very thick rope of cotton fibres, directly after being combined the slivers are separated into rovings. These rovings are then what are used in the spinning process. Generally speaking, for machine processing a roving is about the width of a pencil.Next, several slivers are combined. Each sliver will have thin and thick spots, and by combining several slivers together a more consistent size can be reached. Since combining several slivers produces a very thick rope of cotton fibres, directly after being combined the slivers are separated into rovings. These rovings (or slubbings) are then what are used in the spinning process.

Generally speaking, for machine processing, a roving is about the width of a pencil.

* Drawing frame: Draws the strand out

* Slubbing Frame: adds twist, and winds on to bobbins

* Intermediate Frames: are used to repeat the slubbing process to produce a finer yarn.

* Roving frames: reduces to a finer thread, gives more twist, makes more regular and even in thickness, and winds on to a smaller tube.

Spinning- Yarn manufacture

Spinning:

The spinning machines take the roving, thins it and twists it, creating yarn which it winds onto a bobbin.[12]

In mule spinning the roving is pulled off a bobbin and fed through some rollers, which are feeding at several different speeds.This thins the roving at a consistent rate. If the roving was not a consistent size, then this step could cause a break in the yarn, or could jam the machine. The yarn is twisted through the spinning of the bobbin as the carriage moves out, and is rolled onto a cop as the carriage returns. Mule spinning produces a finer thread than the less skilled ring spinning.

* The mule was an intermittent process, as the frame advanced and returned a distance of 5ft.It was the descendant of 1779 Crompton device. It produces a softer less twisted thread that was favoured for fines and for weft. It requires considerable skill, so was womens work.

* The ring was a descendant of the Arkwright water Frame 1769. It was a continuous process, the yard was coarser, had a greater twist and was stronger so was suited to be warp. Requiring less skill it was mens work. Ring spinning is slow due to the distance the thread must pass around the ring, other methods have been introduced. These are collectively known as Break or Open-end spinning.

Sewing thread, was made of several threads twisted together, or doubled.

Checking:

This is the process where each of the bobbins is rewound to give a tighter bobbin.

Folding and twisting:

Plying is done by pulling yarn from two or more bobbins and twisting it together, in the opposite direction that that in which it was spun. Depending on the weight desired, the cotton may or may not be plied, and the number of strands twisted together varies.[15]

Singe#Textiles and Gassing:

Gassing is the process of passing yarn, as distinct from fabric very rapidly through a series of Bunsen gas flames in a gassing frame, in order to burn off the projecting fibres and make the thread round and smooth and also brighter. Only the better qualities of yarn are gassed, such as that used for voiles, poplins, venetians, gabardines, many Egyptian qualities, etc. There is a loss of weight in gassing, which varies' about 5 to 8 per cent., so that if a 2/60's yarn is required 2/56's would be used. The gassed yarn is darker in shade afterwards, but should not be scorched.

Measurements:

Units of textile measurement:

Cotton Counts:

The number of pieces of thread, 840 yards long needed to make up 1 lb weight. 10 count cotton means that 10x840 yds weighs 1lb. This is coarser than 40 count cotton where 40x840 yards are needed. In the United Kingdom, Counts to 40s are coarse (Oldham Counts), 40 to 80s are medium counts and above 80 is a fine count. In the United States ones to 20s are coarse counts.

* Hank: A length of 7 leas or 840 yards

* Thread: A length of 54 in (the circumference of a warp beam)

* Bundle: Usually 10 lbs

* Lea: A length of 80 threads or 120 yards

* Denier: this is an alternative method. It is defined as a number that is equivalent to the weight in grams of 9000m of a single yarn. 15 denier is finer than 30 denier.

* Tex: is the weight in grams of 1 km of yarn.

The Worsted hank is only 560yd

Weaving-Fabric manufacture:

The weaving process uses a loom. The lengthway threads are known as the warp, and the cross way threads are known as the weft. The warp which must be strong needs to be presented to loom on a warp beam. The weft, passes across the loom in a shuttle, that carries the yarn on a pirn. These pirns are automatically changed by the loom. Thus, the yarn needs to be wrapped onto a beam, and onto pirns before weaving can commence.

Winding:

After being spun and plied, the cotton thread is taken to a warping room where the winding machine takes the required length of yarn and winds it onto warpers bobbins

Warping or beaming:

A Warper:

Racks of bobbins are set up to hold the thread while it is rolled onto the warp bar of a loom. Because the thread is fine, often three of these would be combined to get the desired thread count.[citation needed].

Sizing:

Slasher sizing machine needed for strengthening the warp by adding starch.

Drawing in, Looming:

The process of drawing each end of the warp separately through the dents of the reed and the eyes of the healds, in the order indicated by the draft.

Pirning (Processing the weft):

Pirn winding frame was used to transfer the weft from cheeses of yarn onto the pirns that would fit into the shuttle

Weaving:

At this point, the thread is woven. Depending on the era, one person could manage anywhere from 3 to 100 machines. In the mid nineteenth century, four was the standard number. A skilled weaver in 1925 would run 6 Lancashire Looms. As time progressed new mechanisms were added that stopped the loom any time something went wrong. The mechanisms checked for such things as a broken warp thread, broken weft thread, the shuttle going straight across, and if the shuttle was empty. Forty of these Northrop Looms or automatic looms could be operated by one skilled worker.

A Draper loom in textile museum,Lowell, Massachusetts

The three primary movements of a loom are shedding, picking, and beating-up.

Shedding:

The operation of dividing the warp into two lines, so that the shuttle can pass between these lines. There are two general kinds of sheds-"open" and "closed." Open Shed-The warp threads are moved when the pattern requires it-from one line to the other. Closed Shed-The warp threads are all placed level in one line after each pick.

* Picking:The operation of projecting the shuttle from side to side of the loom through the division in the warp threads. This is done by the overpick or underpick motions. The overpick is suitable for quick-running looms, whereas the underpick is best for heavy or slow looms.

* Beating-up: The third primary movement of the loom when making cloth, and is the action of the reed as it drives each pick of weft to the fell of the cloth.

The Lancashire Loom was the first semi-automatic loom. Jacquard looms and Dobby looms are looms that have sophisticated methods of shedding. They may be separate looms, or mechanisms added to a plain loom. A Northrop Loom was fully automatic and was mass produced between 1909 and the mid 1960s. Modern looms run faster and do not use a shuttle: there are air jet looms, water jet looms and rapier looms.

Measurements:

* Ends and Picks: Picks refer to the weft, ends refer to the warp. The coarseness of the cloth can be expressed as the number of picks and ends per quarter inch square, or per inch square. Ends is always written first. For example: Heavy domestics are made from coarse yarns, such as 10's to 14's warp and weft, and about 48 ends and 52 picks.

associated job titles-

* Piecer

* Scavenger

* Weaver

* Tackler

* Draw boy

* Pirner

Issues:

When a hand loom was located in the home, children helped with the weaving process from an early age. Piecing needs dexterity, and a child can be as productive as an adult. When weaving moves from the home to the mill, children were often allowed to help their older sisters, and laws have to be made to prevent child labour becoming established,

Knitting- Fabric manufacture

A circular knitting machine.

Close-up on the needles.

Knitting by machine is done in two different ways; warp and weft. Weft knitting (as seen in the pictures) is similar in method to hand knitting with stitches all connected to each other horizontally. Various weft machines can be configured to produce textiles from a single spool of yarn or multiple spools depending on the size of the machine cylinder (where the needles are bedded). In a warp knit there are many pieces of yarn and there are vertical chains, zigzagged together by crossing the yarn.

Warp knits do not stretch as much as a weft knit, and it is run-resistant. A weft knit is not run-resistant, but stretches more, this is especially true if spools of Lycra are processed from separate spool containers and interwoven through the cylinder with cotton yarn giving the finished product more flexibility making it less prone to having a 'baggy' appearance. The average t-shirt is a weft knit. [24]

Finishing- Processing of Textiles:

The grey cloth,woven cotton fabric in its loom-state, not only contains impurities, including warp size, but requires further treatment in order to develop its full textile potential. Furthermore, it may receive considerable added value by applying one or more finishing processes.

Desizin:

Depending on the size that has been used, the cloth may be steeped in a dilute acid and then rinsed, or enzymes may be used to break down the size.[27]

Scouring:

Scouring, is a chemical washing process carried out on cotton fabric to remove natural wax and non-fibrous impurities (eg the remains of seed fragments) from the fibres and any added soiling or dirt. Scouring is usually carried in iron vessels called kiers. The fabric is boiled in an alkali, which forms a soap with free fatty acids. (saponification). A kier is usually enclosed, so the solution of sodium hydroxide can be boiled under pressure, excluding oxygen which would degrade the cellulose in the fibre. If the appropriate reagents are used, scouring will also remove size from the fabric although desizing often precedes scouring and is considered to be a separate process known as fabric preparation. Preparation and scouring are prerequisites to most of the other finishing processes. At this stage even the most naturally white cotton fibres are yellowish, and bleaching, the next process, is required.

Bleaching:

Bleaching improves whiteness by removing natural coloration and remaining trace impurities from the cotton; the degree of bleaching necessary is determined by the required whiteness and absorbency. Cotton being a vegetable fibre will be bleached using an oxidizing agent, such as dilute sodium hydrochlorite or dilute hydrogen peroxide. If the fabric is to be dyed a deep shade, then lower levels of bleaching are acceptable, for example. However, for white bed sheetings and medical applications, the highest levels of whiteness and absorbency are essential.

Mercerising:

A further possibility is mercerizing during which the fabric is treated with caustic soda solution to cause swelling of the fibres. This results in improved lustre, strength and dye affinity. Cotton is mercerized under tension, and all alkali must be washed out before the tension is released or shrinkage will take place. Mercerizing can take place directly on grey cloth, or after bleaching. [29]

Many other chemical treatments may be applied to cotton fabrics to produce low flammability, crease resist and other special effects but four important non-chemical finishing treatments are:

Singeing:

Singeing is designed to burn off the surface fibres from the fabric to produce smoothness. The fabric passes over brushes to raise the fibres, then passes over a plate heated by gas flames.

Raising:

Another finishing process is raising. During raising, the fabric surface is treated with sharp teeth to lift the surface fibres, thereby imparting hairiness, softness and warmth, as in flannelette.

Calendering:

Calendering is the third important mechanical process, in which the fabric is passed between heated rollers to generate smooth, polished or embossed effects depending on roller surface properties and relative speeds.

Shrinking (Sanforizing):

Finally, mechanical shrinking (sometimes referred to as sanforizing), whereby the fabric is forced to shrink width and/or lengthwise, creates a fabric in which any residual tendency to shrink after subsequent laundering is minimal.

Dyeing:

Finally, cotton is an absorbent fibre which responds readily to colouration processes. Dyeing, for instance, is commonly carried out with an anionic direct dye by completely immersing the fabric (or yarn) in an aqueous dyebath according to a prescribed procedure. For improved fastness to washing, rubbing and light, other dyes such as vats and reactives are commonly used. These require more complex chemistry during processing and are thus more expensive to apply.

Printing:

Printing, on the other hand, is the application of colour in the form of a paste or ink to the surface of a fabric, in a predetermined pattern. It may be considered as localised dyeing. Printing designs on to already dyed fabric is also possible.

Economic, environmental and political consequences of cotton manufacture:

The growth of cotton is divided into two segments i.e. organic and genetically modified.Cotton crop provides livelihood to millions of people but its production is becoming expensive because of high water consumption, use of expensive pesticides, insecticides and fertiliser. GM products aim to increase disease resistance and reduce the water required. The organic sector was worth $583 million. GM cotton, in 2007, occupied 43% of cotton growing areas.

The consumption of energy in form of water and electricity is relatively high, especially in processes like washing, de-sizing, bleaching, rinsing, dyeing, printing, coating and finishing. Processing is time consuming. The major portion of water in textile industry is used for wet processing of textile (70 per cent). Approximately 25 per cent of energy in the total textile production like fibre production, spinning, twisting, weaving, knitting, clothing manufacturing etc. is used in dyeing. About 34 per cent of energy is consumed in spinning, 23 per cent in weaving, 38 per cent in chemical wet processing and five per cent in miscellaneous processes. Power dominates consumption pattern in spinning and weaving, while thermal energy is the major factor for chemical wet processing.

Processing of other vegetable fibres- other processes:

Flax:

Flax is a bast fibre, which means it comes in bundles under the bark of the Linum usitatissimum plant. The plant flowers and is harvested.

* Retting

* Breaking

* Scutching

* Hackling or combing

It is now treated like cotton.

Jute:

Jute is a bast fibre, which comes from the inner bark of the plants of the Corchorus genus. It is retted like flax, sundried and baled. When spinning a small amount of oil must be added to the fibre. It can be bleached and dyed. It was used for sacks and bags but is now used for the backing for carpets.[32]

Hemp:

Hemp is a bast fibre from the inner bark of Cannabis sativa. It is difficult to bleach, it is used for making cord and rope.

* Retting

* Separating

* Pounding

Other bast fibres:

These bast fibres can also be used: kenaf, urena, ramie, nettle.

Other leaf fibres:

Sisal is the main leaf fibre used; others are: abacá and henequen.

Processing of Protein fibres:

Wool comes from domesticated sheep. It forms two products, woolens and worsteds. The sheep has two sorts of wool and it in the inner coat that is used. This can be mixed with wool that has been recovered from rags. Shoddy is the term for recovered wool that is not matted, while mungo comes from felted wool. Extract is recovered chemically from mixed cotton/wool fabrics.

The fleece is cut in one piece from the sheep.This is then skirted to remove the soiled wool, and baled. It is graded into long wool where the fibres can be up to 15 in, but anything over 2.5 inches is suitable for combing into worsteds. Fibres less than that form short wool and are described as clothing or carding wool.

At the mill the wool is scoured in a detergent to remove grease (the yolk) and impurities. This is done mechanically in the opening machine. Vegetable matter can be removed chemically using sulkphuric acid (carbonising). Washing uses a solution of soap and sodium carbonate. The wool is oiled before carding or combing.

Woollens: Use noils from the worsted combs, mungo and shoddy and new short wool

Worsteds:

Combing: Oiled slivers are wound into laps, and placed in the circular comber. The worsted yarn gathers together to form a top. The shorter fibres or noils remain behind and are removed with a knife.

Angora:

Silk:

The processes in silk production are similar to those of cotton but take account that reeeled silk is a continuous fibre. The terms used are different.

* Opening bales. Assorting skeins:where silk is sorted by colour, size and quality, scouring: where the silk is washed in water of 40 degrees for 12 hours to remove the natural gum, drying:either by steam heating or centrifuge, softening: by rubbing to remove any remaining hard spots.

* Silk throwing (winding). The skeins are placed on a reel in a frame with many others. The silk is wound onto spools or bobbins.

* Doubling and twisting. The silk is far too fine to be woven, so now it is doubled and twisted to make the warp, known as organzine and the weft, known as tram. In organzine each single is given a few twists per inch (tpi), and combine with several other singles counter twisted hard at 10 to 14 tpi. In tram the two singles are doubled with each other with a light twist, 3 to 6 tpi. Sewing thread is two tram threads, hard twisted and machine-twist is made of three hard twisted tram threads. Tram for the crepe process is twisted at up to 80 tpi to make it 'kick up'.

* Stretching. The thread is tested for consistent size. Any uneven thickness is stretched out. The resulting thread is reeled into containing 500 yds to 2500 yds. The skeins are about 50 in in loop length.

* Dyeing: the skeins are scoured again, and discoloration removed with a sulphur process. This weakens the silk. The skeins are now tinted or dyed. They are dried and rewound onto bobbins, spools and skeins. Looming, and the weaving process on power looms is the same as with cotton.

* Weaving. The organzine is now warped. This is a similar process to in cotton. Firstly, thirty threads or so are wound onto a warping reel, and then using the warping reels, the threads are beamed. A thick layer of paper is lain between each layer on the beam to stop entangling.

Processing of man made fibres:

Discussion of types of man made fibres:

Synthetic fibres are the result of extensive development by scientists to improve upon the naturally occurring animal and plant fibres. In general, synthetic fibers are created by forcing, or extruding, fibre forming materials through holes (called spinnerets) into the air, thus forming a thread. Before synthetic fibres were developed, cellulose fibers were made from natural cellulose, which comes from plants.

The first artificial fibre, known as art silk from 1799 onwards, became known as viscose around 1894, and finally rayon in 1924. A similar product known as cellulose acetate was discovered in 1865. Rayon and acetate are both artificial fibres, but not truly synthetic, being made from wood. Although these artificial fibres were discovered in the mid-nineteenth century, successful modern manufacture began much later in the 1930s. Nylon, the first synthetic fibre, made its debut in the United States as a replacement for silk, and was used for parachutes and other military uses.

The techniques used to process these fibres in yarn are essentially the same as with natural fibres, modifications have to be made as these fibers are of great length, and have no texture such as the scales in cotton and wool that aid meshing.

to be continued...................

Textile Weaving

2010-04-04T23:47:00.000-07:00

Weaving is the textile art in which two distinct sets of yarns or threads, called the warp and the filling or weft (older woof), are interlaced with each other to form a fabric or cloth. The warp threads run lengthways of the piece of cloth, and the weft runs across from side to side.

Cloth is woven on a loom, a device for holding the warp threads in place while the filling threads are woven through them. Weft is an old English word meaning "that which is woven".

The manner in which the warp and filling threads interlace with each other is known as the weave. The three basic weaves are plain weave, satin weave, and twill, and the majority of woven products are created with one of these weaves.

Woven cloth can be plain (in one colour or a simple pattern), or it can be woven in decorative or artistic designs, including tapestries. Fabric in which the warp and/or weft is tie-dyed before weaving is called ikat.

The ancient art of handweaving, along with hand spinning, remains a popular craft. The majority of commercial fabrics in the West are woven on computer-controlled Jacquard looms. In the past, simpler fabrics were woven on dobby looms, while the Jacquard harness adaptation was reserved for more complex patterns. Some believe the efficiency of the Jacquard loom, with its Jacquard weaving process, makes it more economical for mills to use them to weave all of their fabrics, regardless of the complexity of the design.

Process:

In general, weaving involves the interlacing of two sets of threads at right angles to each other: the warp and the weft. The warp are held taut and in parallel order, typically by means of a loom, though some forms of weaving may use other methods. The loom is warped (or dressed) with the warp threads passing through heddles on two or more harnesses. The warp threads are moved up or down by the harnesses creating a space called the shed. The weft thread is wound onto spools called bobbins. The bobbins are placed in a shuttle which carries the weft thread through the shed. The raising and lowering sequence of warp threads gives rise to many possible weave structures:

* plain weave,
* twill weave,
* satin weave, and
* complex computer-generated interlacings.

Both warp and weft can be visible in the final product. By spacing the warp more closely, it can completely cover the weft that binds it, giving a warpfaced textile such as rep weave. Conversely, if the warp is spread out, the weft can slide down and completely cover the warp, giving a weftfaced textile, such as a tapestry or a Kilim rug. There are a variety of loom styles for hand weaving and tapestry. In tapestry, the image is created by placing weft only in certain warp areas, rather than across the entire warp width.

Ancient and traditional cultures:

There are some indications that weaving was already known in the Palaeolithic era. An indistinct textile impression has been found at Pavlov, Moravia. Neolithic textiles are well known from finds in pile dwellings in Switzerland. One extant fragment from the Neolithic was found in Fayum at a site which dates to about 5000 BCE. This fragment is woven at about 12 threads by 9 threads per cm in a plain weave. Flax was the predominant fibre in Egypt at this time and continued popularity in the Nile Valley, even after wool became the primary fibre used in other cultures around 2000 BCE. Another Ancient Egyptian item, known as the Badari dish, depicts a textile workshop. This item, catalogue number UC9547, is now housed at the Petrie Museum and dates to about 3600 BCE. Enslaved women worked as weavers during the Sumerian Era. They would wash wool fibers in hot water and wood-ash soap and then dry them. Next, they would beat out the dirt and card the wool. The wool was then graded, bleached, and spun into a thread. The spinners would pull out fibers and twist them together. This was done by either rolling fibers between palms or using a hooked stick. The thread was then placed on a wooden or bone spindle and rotated on a clay whorl which operated like a flywheel.

The slaves would then work in three-woman teams on looms, where they stretched the threads, after which they passed threads over and under each other at perpendicular angles. The finished cloth was then taken to a fuller.

American Southwest:

Textile weaving, using cotton dyed with pigments, was a dominant craft among pre-contact tribes of the American southwest, including various Pueblo peoples, the Zuni, and the Ute tribes. The first Spaniards to visit the region wrote about seeing Navajo blankets. With the introduction of Navajo-Churro sheep, the resulting woolen products have become very well known. By the 1700s the Navajo had begun to import yarn with their favorite color, Bayeta red. Using an upright loom, the Navajos wove blankets and then rugs after the 1880s for trade. Navajo traded for commercial wool, such as Germantown, imported from Pennsylvania. Under the influence of European-American settlers at trading posts, Navajos created new and distinct styles, including "Two Gray Hills" (predominantly black and white, with traditional patterns), "Teec Nos Pos" (colorful, with very extensive patterns), "Ganado" (founded by Don Lorenzo Hubbell), red dominated patterns with black and white, "Crystal" (founded by J. B. Moore), Oriental and Persian styles (almost always with natural dyes), "Wide Ruins," "Chinlee," banded geometric patterns, "Klagetoh," diamond type patterns, "Red Mesa" and bold diamond patterns. Many of these patterns exhibit a fourfold symmetry, which is thought to embody traditional ideas about harmony.

Islamic world:

Hand weaving of Persian carpets and kilims has been an important element of the tribal crafts of many of the subregions of modern day Iran. Examples of carpet types are the Lavar Kerman carpet from Kerman and the Seraband rug from Arak.

An important innovation in weaving that was developed in the Muslim world during the Islamic Golden Age was the introduction of foot pedals to operate a loom. The first such devices appeared in Syria, Iran and Islamic parts of East Africa, where "the operator sat with his feet in a pit below a fairly low-slung loom." By 1177, it was further developed in Al-Andalus, where having the mechanism was "raised higher above the ground on a more substantial frame." This type of loom spread to the Christian parts of Spain and soon became popular all over medieval Europe.

Europe:

Dark Age and Medieval Europe:

Weighted-warp looms were commonplace in Europe until the development of more advanced looms around the 10th-11th centuries. Especially in colder climates, where a large floor loom would take up too much valuable floor space, the more primitive looms remained in use until the 20th Century to produce "homespun" cloth for individual family needs. The primary material woven in most of Europe was wool, though linen was also common, and imported silk thread was occasionally made into cloth. Both men and women were weavers, though the task often fell to the wife of a farming household. Fabric width was limited to the reach of the weaver, but was sufficient for the tunic-style garments worn in much of Europe at the time. A plain weave or twill was common, since professional weavers with skills to produce better fabrics were rare.

Weaving was a strictly local enterprise until later in the period, when larger weaving operations sprung up in places like Brugges, in Flanders. Within this setting, master weavers could improve their craft and pass skills along to apprentices. As the Middle Ages progressed, significant trade in fine cloth developed, and loom technology improved to allow very thin threads to be woven. Weaver's guilds (and associated craft guilds, like fullers) gained significant political and economic power in some of the bigger weaving cities.

Colonial America:

Colonial America was heavily reliant on Great Britain for manufactured goods of all kinds. British policy was to encourage the production of raw materials in colonies. Weaving was not prohibited, but the export of British wool was. As a result many people wove cloth from locally produced fibers in Colonial America.

In Colonial times the colonists mostly used wool, cotton and flax (linen) for weaving, though hemp fiber could be made into serviceable canvas and heavy cloth also. They could get one cotton crop each fall, but until the invention of the cotton gin it was a labor-intensive process to separate the seeds from the cotton fiber. Flax and hemp were harvested in the summer, and the stalks rendered for the long fibers within. Wool could be sheared up to twice yearly, depending on the breed of sheep.

A plain weave was preferred in Colonial times, and the added skill and time required to make more complex weaves kept them from common use in the average household. Sometimes designs were woven into the fabric but most were added after weaving using wood block prints or embroidery.

Textile Knitting

2010-04-04T23:30:00.000-07:00

Knitting is a method by which thread or yarn may be turned into cloth. Knitting consists of loops called stitches pulled through each other. The active stitches are held on a needle until another loop can be passed through them.

Knitting may be done by hand or by machine. By hand, there are numerous styles and methods. Flat knitting, which can be done on two straight needles or a circular needle, produces a length of cloth, while circular knitting, which is done on circular or double-pointed needles, produces a seamless tube.

Different yarns and knitting needles may be used to achieve different end products by giving the final piece a different colour, texture, weight, or integrity. Using needles of varying sharpness and thickness as well as different varieties of yarn adds to the effect.

Structure:

Courses and wales:

Like weaving, knitting is a technique for producing a two-dimensional fabric from a one-dimensional yarn or thread. In weaving, threads are always straight, running parallel either lengthwise (warp threads) or crosswise (weft threads). By contrast, the yarn in knitted fabrics follows a meandering path (a course), forming symmetric loops (also called bights or stitches) symmetrically above and below the mean path of the yarn. These meandering loops can be stretched easily in different directions, which gives knitting much more elasticity than woven fabrics; depending on the yarn and knitting pattern, knitted garments can stretch as much as 500%. For this reason, knitting was initially developed for garments that must be elastic or stretch in response to the wearer's motions, such as socks and hosiery. For comparison, woven garments stretch mainly along one direction (the bias) and not very much, unless they are woven from stretchable material such as spandex. Knitted garments are often more form-fitting than woven garments, since their elasticity allows them to follow the body's curvature closely; by contrast, curvature is introduced into most woven garments only with sewn darts, flares, gussets and gores, the seams of which lower the elasticity of the woven fabric still further. Extra curvature can be introduced into knitted garments without seams, as in the heel of a sock; the effect of darts, flares, etc. can be obtained with short rows or by increasing/decreasing the number of stitches. Thread used in weaving is usually much finer than the yarn used in knitting, which can give the knitted fabric more bulk and less drape than a woven fabric.

If they are not secured, the loops of a knitted course will come undone when their yarn is pulled; this is known as ripping out, unravelling knitting, or humorously, frogging[1]. To secure a stitch, at least one new loop is passed through it. Although the new stitch is itself unsecured ("active" or "live"), it secures the stitch(es) suspended from it. A sequence of stitches in which each stitch is suspended from the next is called a wale.[2] To secure the initial stitches of a knitted fabric, a method for casting on is used; to secure the final stitches in a wale, one uses a method of binding off. During knitting, the active stitches are secured mechanically, either from individual hooks (in knitting machines) or from a knitting needle or frame in hand-knitting.

Weft and warp knitting:

There are two major varieties of knitting: weft knitting and warp knitting.[3] In the more common weft knitting, the wales are perpendicular to the course of the yarn; however, in warp knitting, the wales and courses run roughly parallel. In weft knitting, the entire fabric may be produced from a single yarn, by adding stitches to each wale in turn, moving across the fabric as in a raster scan. By contrast, in warp knitting, one yarn is required for every wale. Since a typical piece of knitted fabric may have hundreds of wales, warp knitting is typically done by machine, whereas weft knitting is done by both hand and machine.[4] Warp-knitted fabrics such as tricot and milanese are resistant to runs, and are commonly used in lingerie.

Weft-knit fabrics may also be knit with multiple yarns, usually to produce interesting color patterns. The two most common approaches are intarsia and double knitting. In intarsia, the yarns are used in well-segregated regions, e.g., a red apple on a field of green; in that case, the yarns are kept on separate spools and only one is knitted at any time. In the more complex double knitting, two or more yarns alternate repeatedly within one row and all the yarns must be carried along the row, as seen in Fair Isle sweaters. Double knitting can produce two separate knitted fabrics simultaneously, e.g., two socks; however, the two fabrics are usually integrated into one, giving it great warmth and excellent drape.

Knit and purl stitches:

In securing the previous stitch in a wale, the next stitch can pass through the previous loop either from below or above. If the former, the stitch is denoted as a knit stitch or a plain stitch; if the latter, as a purl stitch. The two stitches are related in that a knit stitch seen from one side of the fabric appears as a purl stitch on the other side.

The two types of stitches have a different visual effect; the knit stitches look like "V"'s stacked vertically, whereas the purl stitches look like a wavy horizontal line across the fabric. Patterns and pictures can be created in knitted fabrics by using knit and purl stitches as "pixels"; however, such pixels are usually rectangular, rather than square, depending on the gauge of the knitting. Individual stitches, or rows of stitches, may be made taller by drawing more yarn into the new loop (an elongated stitch), which is the basis for uneven knitting: a row of tall stitches may alternate with one or more rows of short stitches for an interesting visual effect. Short and tall stitches may also alternate within a row, forming a fish-like oval pattern.

Two courses of red yarn illustrating two basic fabric types. The lower red course is knit into the white row below it and is itself knit on the next row; this produces stockinette stitch. The upper red course is purled into the row below and then is knit, consistent with garter stitch.

In the simplest knitted fabrics, all of the stitches are knit or purl; these fabrics are denoted as stockinette and reverse stockinette, respectively. Vertical stripes (ribbing) are possible by having alternating wales of knit and purl stitches; for example, a common choice is 2x2 ribbing, in which two wales of knit stitches are followed by two wales of purl stitches, etc. Horizontal striping (welting) is also possible, by alternating rows of knit and purl stitches; the simplest of these is garter stitch, so-called because its great elasticity made it well-suited for garters. Checkerboard patterns (basketweave) are also possible, the smallest of which is known as seed stitch: the stitches alternate between knit and purl in every wale and along every row.

Fabrics in which the number of knit and purl stitches are not the same, such as stockinette, have a tendency to curl; by contrast, those in which knit and purl stitches are arranged symmetrically (such as ribbing, garter stitch or seed stitch) tend to lie flat and drape well. Wales of purl stitches have a tendency to recede, whereas those of knit stitches tend to come forward. Thus, the purl wales in ribbing tend to be invisible, since the neighboring knit wales come forward. Conversely, rows of purl stitches tend to form an embossed ridge relative to a row of knit stitches. This is the basis of shadow knitting, in which the appearance of a knitted fabric changes when viewed from different directions.

Typically, a new stitch is passed through a single unsecured ("active") loop, thus lengthening that wale by one stitch. However, this need not be so; the new loop may be passed through an already secured stitch lower down on the fabric, or even between secured stitches (a dip stitch). Depending on the distance between where the loop is drawn through the fabric and where it is knitted, dip stitches can produce a subtle stippling or long lines across the surface of the fabric, e.g., the lower leaves of a flower. The new loop may also be passed between two stitches in the present row, thus clustering the intervening stitches; this approach is often used to produce a smocking effect in the fabric. The new loop may also be passed through two or more previous stitches, producing a decrease and merging wales together. The merged stitches need not be from the same row; for example, a tuck can be formed by knitting stitches together from two different rows, producing a raised horizontal welt on the fabric.

Not every stitch in a row need be knitted; some may be left as is and knitted on a subsequent row. This is known as slip-stitch knitting.The slipped stitches are naturally longer than the knitted ones. For example, a stitch slipped for one row before knitting would be roughly twice as tall as its knitted counterparts. This can produce interesting visual effects, although the resulting fabric is more rigid, because the slipped stitch "pulls" on its neighbours and is less deformable. Slip-stitch knitting plays an important role in mosaic knitting, an important technique in hand-knitting patterned fabrics; mosaic-knit fabrics tend to be stiffer than patterned fabrics produced by other methods such as Fair-Isle knitting.

In some cases, a stitch may be deliberately left unsecured by a new stitch and its wale allowed to disassemble. This is known as drop-stitch knitting, and produces a vertical ladder of see-through holes in the fabric, corresponding to where the wale had been.

Right- and left-plaited stitches:

Both knit and purl stitches may be twisted: usually once if at all, but sometimes twice and (very rarely) thrice. When seen from above, the twist can be clockwise (right yarn over left) or counterclockwise (left yarn over right); these are denoted as right- and left-plaited stitches, respectively. Hand-knitters generally produce right-plaited stitches by knitting or purling through the back loops, i.e., passing the needle through the initial stitch in an unusual way, but wrapping the yarn as usual. By contrast, the left-plaited stitch is generally formed by hand-knitters by wrapping the yarn in the opposite way, rather than by any change in the needle.

Although they are mirror images in form, right- and left-plaited stitches are functionally equivalent. Both types of plaited stitches gives a subtle but interesting visual texture, and tend to draw the fabric inwards, making it stiffer. Plaited stitches are a common method for knitting jewelry from fine metal wire.

Edges and joins between fabrics:

The initial and final edges of a knitted fabric are known as the cast-on and bound-off edges. The side edges are known as the selvages; the word derives from "self-edges", meaning that the stitches do not need to be secured by anything else. Many types of selvages have been developed, with different elastic and ornamental properties.

Vertical and horizontal edges can be introduced within a knitted fabric, e.g., for button holes, by binding off and re-casting on again (horizontal) or by knitting the fabrics on either side of a vertical edge separately.

Two knitted fabrics can be joined by embroidery-based grafting methods, most commonly the Kitchener stitch. New wales can be begun from any of the edges of a knitted fabric; this is known as picking up stitches and is the basis for entrelac, in which the wales run perpendicular to one another in a checkerboard pattern.

Types:

Flat knitting versus circular knitting:

Circular knitting (also called "knitting in the round") is a form of knitting that creates a seamless tube. Knitting is worked in rounds (the equivalent of rows in flat knitting) in a spiral. Originally, circular knitting was done using a set of four or five double-pointed knitting needles. Later, circular needles were invented. A circular needle resembles two short knitting needles connected by a cable between them. Flat knitting, on the other hand, is used, in its most basic form, to make flat, rectangular pieces of cloth.[11] It is done with two straight knitting needles and is worked in rows, horizontal lines of stitches.

Circular knitting is employed to create pieces that are circular or tube-shaped, such as hats, socks, mittens, and sleeves. Flat knitting is usually used to knit flat pieces like scarves, blankets, afghans, and the backs and fronts of sweaters.

There is also such a thing as finger knitting. It is not done like on needles, it is done on your fingers. This produces a tube-like piece.

Felting:

Felting is a technique for joining wool fibres. The finished product is put in a hot wash and agitated until it has shrunk. The end result is typically smaller. Bags, mittens, socks and hats are just a few ideas of items that could be felted.

Properties of fabrics:

The topology of a knitted fabric is relatively complex. Unlike woven fabrics, where strands usually run straight horizontally and vertically, yarn that has been knitted follows a loopy path along its row, as with the red strand in the diagram at left, in which the loops of one row have all been pulled through the loops of the row below it.

Because there is no single straight line of yarn anywhere in the pattern, a knitted piece can stretch in all directions. This elasticity is unavailable from woven fabrics, which only stretch along the bias. Many modern stretchy garments, even as they rely on elastic synthetic materials for some stretch, also achieve at least some of their stretch through knitted patterns.

Close-up of stockinette stitch

Close-up of reverse stockinette stitch

The basic knitted fabric (as in the diagram, and usually called a stocking or stockinette pattern) has a definite "right side" and "wrong side". On the right side, the visible portions of the loops are the verticals connecting two rows, arranged in a grid of V shapes. On the wrong side, the ends of the loops are visible, both the tops and bottoms, creating a much more bumpy texture sometimes called reverse stockinette. (Despite being the "wrong side," reverse stockinette is frequently used as a pattern in its own right.) Because the yarn holding rows together is all on the front, and the yarn holding side-by-side stitches together is all on the back, stockinette fabric has a strong tendency to curl toward the front on the top and bottom, and toward the back on the left and right side.

Stitches can be worked from either side, and various patterns are created by mixing regular knit stitches with the "wrong side" stitches, known as purl stitches, either in columns (ribbing), rows (garter, welting), or more complex patterns. Each such fabric has different properties: a garter stitch has much more vertical stretch, while ribbing stretches much more horizontally. Because of their front-back symmetry, these two fabrics have little curl, making them popular as edging, even when their stretch properties are not desired.

Different combinations of knit and purl stitches, along with more advanced techniques, generate fabrics of considerably variable consistency, from gauzy to very dense, from highly stretchy to relatively stiff, from flat to tightly curled, and so on.

Materials:

Yarn for hand-knitting is usually sold as balls or skeins (hanks), although it may also be wound on spools or cones. Skeins and balls are generally sold with a yarn-band, a label that describes the yarn's weight, length, dye lot, fiber content, washing instructions, suggested needle size, likely gauge, etc. It is common practice to save the yarn band for future reference, especially if additional skeins must be purchased. Knitters generally ensure that the yarn for a project comes from a single dye lot. The dye lot specifies a group of skeins that were dyed together and thus have precisely the same color; skeins from different dye-lots, even if very similar in color, are usually slightly different and may produce a visible stripe when knitted together. If a knitter buys insufficient yarn of a single dye lot to complete a project, additional skeins of the same dye lot can sometimes be obtained from other yarn stores or online.

The thickness or weight of the yarn is a significant factor in determining the gauge, i.e., how many stitches and rows are required to cover a given area for a given stitch pattern. Thicker yarns generally require thicker knitting needles, whereas thinner yarns may be knit with thick or thin needles. Hence, thicker yarns generally require fewer stitches, and therefore less time, to knit up a given garment. Patterns and motifs are coarser with thicker yarns; thicker yarns produce bold visual effects, whereas thinner yarns are best for refined patterns. Yarns are grouped by thickness into six categories: superfine, fine, light, medium, bulky and superbulky; quantitatively, thickness is measured by the number of wraps per inch (WPI). The related weight per unit length is usually measured in tex or dernier.

Transformation of a hank of lavender silk yarn (top) into a ball in which the knitting yarn emerges from the center (bottom). The latter is better for knitting, since the yarn is much less likely to tangle.

Before knitting, the knitter will typically transform a hank into a ball where the yarn emerges from the center of the ball; this making the knitting easier by preventing the yarn from becoming easily tangled. This transformation may be done by hand, or with a device known as a ballwinder. When knitting, some knitters enclose their balls in jars to keep them clean and untangled with other yarns; the free yarn passes through a small hole in the jar-lid.

A yarn's usefulness for a knitting project is judged by several factors, such as its loft (its ability to trap air), its resilience (elasticity under tension), its washability and colorfastness, its hand (its feel, particularly softness vs. scratchiness), its durability against abrasion, its resistance to pilling, its hairiness (fuzziness), its tendency to twist or untwist, its overall weight and drape, its blocking and felting qualities, its comfort (breathability, moisture absorption, wicking properties) and of course its look, which includes its color, sheen, smoothness and ornamental features. Other factors include allergenicity; speed of drying; resistance to chemicals, moths, and mildew; melting point and flammability; retention of static electricity; and the propensity to become stained and to accept dyes. Different factors may be more significant than others for different knitting projects, so there is no one "best" yarn. The resilience and propensity to (un)twist are general properties that affect the ease of hand-knitting. More resilient yarns are more forgiving of irregularities in tension; highly twisted yarns are sometimes difficult to knit, whereas untwisting yarns can lead to split stitches, in which not all of the yarn is knitted into a stitch. A key factor in knitting is stitch definition, corresponding to how well complicated stitch patterns can be seen when made from a given yarn. Smooth, highly spun yarns are best for showing off stitch patterns; at the other extreme, very fuzzy yarns or eyelash yarns have poor stitch definition, and any complicated stitch pattern would be invisible.

The two possible twists of yarn:

Although knitting may be done with ribbons, metal wire or more exotic filaments, most yarns are made by spinning fibers. In spinning, the fibers are twisted so that the yarn resists breaking under tension; the twisting may be done in either direction, resulting in an Z-twist or S-twist yarn. If the fibers are first aligned by combing them, the yarn is smoother and called a worsted; by contrast, if the fibers are carded but not combed, the yarn is fuzzier and called woolen-spun. The fibers making up a yarn may be continuous filament fibers such as silk and many synthetics, or they may be staples (fibers of an average length, typically a few inches); naturally filament fibers are sometimes cut up into staples before spinning. The strength of the spun yarn against breaking is determined by the amount of twist, the length of the fibers and the thickness of the yarn. In general, yarns become stronger with more twist (also called worst), longer fibers and thicker yarns (more fibers); for example, thinner yarns require more twist than do thicker yarns to resist breaking under tension. The thickness of the yarn may vary along its length; a slub is a much thicker section in which a mass of fibers is incorporated into the yarn.

The spun fibers are generally divided into animal fibers, plant and synthetic fibers. These fiber types are chemically different, corresponding to proteins, carbohydrates and synthetic polymers, respectively. Animal fibers include silk, but generally are long hairs of animals such as sheep (wool), goat (angora, or cashmere goat), rabbit (angora), llama, alpaca, dog, cat, camel, yak, and muskox (qiviut). Plants used for fibers include cotton, flax (for linen), bamboo, ramie, hemp, jute, nettle, raffia, yucca, coconut husk, banana trees, soy and corn. Rayon and acetate fibers are also produced from cellulose mainly derived from trees. Common synthetic fibers include acrylics,[19] polyesters such as dacron and ingeo, nylon and other polyamides, and olefins such as polypropylene. Of these types, wool is generally favored for knitting, chiefly owing to its superior elasticity, warmth and (sometimes) felting; however, wool is generally less convenient to clean and some people are allergic to it. It is also common to blend different fibers in the yarn, e.g., 85% alpaca and 15% silk. Even within a type of fiber, there can be great variety in the length and thickness of the fibers; for example, Merino wool and Egyptian cotton are favored because they produce exceptionally long, thin (fine) fibers for their type.

A single spun yarn may be knitted as is, or braided or plied with another. In plying, two or more yarns are spun together, almost always in the opposite sense from which they were spun individually; for example, two Z-twist yarns are usually plied with an S-twist. The opposing twist relieves some of the yarns' tendency to curl up and produces a thicker, balanced yarn. Plied yarns may themselves be plied together, producing cabled yarns or multi-stranded yarns. Sometimes, the yarns being plied are fed at different rates, so that one yarn loops around the other, as in bouclé. The single yarns may be dyed separately before plying, or afterwards to give the yarn a uniform look.

The dyeing of yarns is a complex art. Yarns need not be dyed; or they may be dyed one color, or a great variety of colors. Dyeing may be done industrially, by hand or even hand-painted onto the yarn. A great variety of synthetic dyes have been developed since the synthesis of indigo dye in the mid-19th century; however, natural dyes are also possible, although they are generally less brilliant. The color-scheme of a yarn is sometimes called its colorway. Variegated yarns can produce interesting visual effects, such as diagonal stripes; conversely, a variegated yarn may frustrate an otherwise good knitting pattern by producing distasteful color combinations.

Tools:

1.Needles:

The process of knitting has three basic tasks:

1. the active (unsecured) stitches must be held so they don't drop

2. these stitches must be released sometime after they are secured

3. new bights of yarn must be passed through the fabric, usually through active stitches, thus securing them.

In very simple cases, knitting can be done without tools, using only the fingers to do these tasks; however, knitting is usually carried out using tools such as knitting needles, knitting machines or rigid frames. Depending on their size and shape, the rigid frames are called knitting boards, knitting rings (also called knitting looms) or knitting spools (also known as knitting knobbies, knitting nancies, or corkers). Other tools are used to prepare yarn for knitting, to measure and design knitted garments, or to make knitting easier or more comfortable.

Knitting needles in a variety of sizes (US 2, 4, 5, 6, 7, 8, 9, 10, 11, 13 and 15 from the bottom). The US size 7 and 15 needles are bamboo and wood, respectively, whereas the others are aluminum. Having a smoother surface, metal needles tend to produce faster knitting but stitches are more likely to slide off by accident.

There are three basic types of knitting needles (also called "knitting pins"). The first and most common type consists of two slender, straight sticks tapered to a point at one end, and with a knob at the other end to prevent stitches from slipping off. Such needles are usually 10-16 inches long but, due to the compressibility of knitted fabrics, may be used to knit pieces significantly wider. The most important property of needles is their diameter, which ranges from below 2 mm to 25 mm (roughly 1 inch). The diameter affects the size of stitches, which affects the gauge of the knitting and the elasticity of the fabric. Thus, a simple way to change gauge is to use different needles, which is the basis of uneven knitting. Although knitting needle diameter is often measured in millimeters, there are several different size systems, particularly those specific to the United States, the United Kingdom and Japan; a conversion table is given at knitting needle. Such knitting needles may be made out of any materials, but the most common materials are metals, wood, bamboo, and plastic. Different materials have different frictions and grip the yarn differently; slick needles such as metallic needles are useful for swift knitting, whereas rougher needles such as bamboo are less prone to dropping stitches. The knitting of new stitches occurs only at the tapered ends, and needles with lighted tips have been sold to allow knitters to knit in the dark.

Double-pointed knitting needles usually come in sets of four (US size 1, on right) or five (US size 8, on left).

The second type of knitting needles are straight, double-pointed knitting needles (also called "dpns"). Double-pointed needles are tapered at both ends, which allows them to be knit from either end. Dpns are typically used for circular knitting, especially smaller tube-shaped pieces such as sleeves, collars, and socks; usually one needle is active while the others hold the remaining active stitches. Dpns are somewhat shorter (typically 7 inches) and are usually sold in sets of four or five.

Circular knitting needles in three different lengths and sizes. The tips of the outermost, longest one is US size 5 and chrome-plated for speed, whereas the innermost tips are wood and US size 15; the middle red metal tips are US size 9.

Cable needles are a special case of dpns, although they usually are not straight, but dimpled in the middle. Cable needles are typically very short (a few inches), and are used to hold stitches temporarily while others are being knitted. Cable patterns are made by permuting the order of stitches; although one or two stitches may be held by hand or knit out of order, cables of three or more generally require a cable needle.

The third needle type consists of circular needles, which are long, flexible double-pointed needles. The two tapered ends (typically 5 inches (130 mm) long) are rigid and straight, allowing for easy knitting; however, the two ends are connected by a flexible strand (usually nylon) that allows the two ends to be brought together.

Circular needles are typically 24-60 inches long, and are usually used singly or in pairs; again, the width of the knitted piece may be significantly longer than the length of the circular needle. Special kits are available that allow circular needles of various lengths and diameters to be made as needed; rigid ends of various diameters may be screwed into strands of various lengths. The ability to work from either end of one needle is convenient in several types of knitting, such as slip-stitch versions of double knitting. Circular needles may be used for flat or circular knitting.

Industrial applications:

Industrially, metal wire is also knitted into a metal fabric for a wide range of uses including the filter material in cafetieres, catalytic converters for cars and many other uses. These fabrics are usually manufactured on circular knitting machines that would be recognised by conventional knitters as sock machines.

Graffiti:

In the past few years, a practice called yarn bombing, or the use of knitted or crocheted cloth to modify and beautify one's (usually outdoor) surroundings, emerged in the U.S. and spread worldwide.[21] Yarn bombers sometimes target existing pieces of graffiti for beautification. For instance, Dave Cole is a contemporary sculpture artist who practiced knitting as graffiti for a large-scale public art installation in Melbourne Australia for the Big West Arts Festival in 2009. The work was vandalized the night of its completion.

Charity:

Knitting garments for free distribution to others has become common practice among knitting groups. Girls and women knit socks, sweaters, scarves, mittens, gloves, and hats for soldiers in Crimea, the American Civil War, and the Boer Wars; this practice continued in both world wars and Korea, and continues for soldiers in Iraq and Afghanistan. In the historical projects, yarn companies provided patterns approved by the various branches of the armed services; the modern projects usually entail the knitting of helmet liners; the liners provided for soldiers must be of 100% worsted weight wool.

One of the most successful modern projects has been the chemo-cap project, started in Nazareth, Pennsylvania in 2002 in memory of a woman who died of uterine cancer. The chemo cap project, and other related projects such as the Headhuggers, No Hair Day project, provide caps and head coverings for chemotherapy patients. Like the helmet liner projects, yarn companies offer free patterns; fiber must be 100% cotton or acrylic, and machine washable.

Textile Spinning

2010-04-04T23:08:00.000-07:00

Spinning is an ancient textile art in which plant, animal or synthetic fibers are twisted together to form yarn. For thousands of years, fiber was spun by hand using simple tools, the spindle and distaff. Only in the High Middle Ages did the spinning wheel increase the output of individual spinners, and mass-production only arose in the 18th century with the beginnings of the Industrial Revolution. Hand-spinning remains a popular handicraft.

Spinning in conversion of fibers into yarn. These fibers can be natural fibers (cotton) or manmade fibers (polyester). Spinning also entails production of manmade filament yarn (yarn that is not made from fibers). Final product of spinning is yarn.

Cotton value chain starts from Ginning that adds value to it by separating cotton from seed and impurities. However Spinning can be called as the first process in the chain that adds value to cotton by converting into a new product i.e. conversion of ginned cotton into cotton yarn. Spinning is the foundation process and all the subsequent value additions i.e. Weaving, Knitting, Processing, Garments and Made ups, depend upon it. Any variation in quality of Spinning product directly effects the entire value chain.

Characteristics of spun yarn vary based on the material used, fiber length and alignment, quantity of fiber used, and degree of twist.

Hand spinning:

A man from Ramallah spinning wool. Hand tinted photograph from 1919, restored.

Rhof-kardierenSpinnenStricken.ogg

Play video

Irreler Bauerntradition shows carding, spinning and knitting in the Roscheider Hof, Open Air Museum

The origins of spinning fiber to make string or yarn are lost in time, but archaeological evidence in the form of representation of string skirts has been dated to the Upper Paleolithic era, some 20,000 years ago.In the most primitive type of spinning, tufts of animal hair or plant fiber are rolled down the thigh with the hand, and additional tufts are added as needed until the desired length of spun fiber is achieved. Later, the fiber is fastened to a stone which is twirled round until the yarn is sufficiently twisted, whereupon it is wound upon the stone and the process repeated over and over.

The next method of twisting yarn is with the spindle, a straight stick eight to twelve inches long on which the thread is wound after twisting. At first the stick had a cleft or split in the top in which the thread was fixed. Later, a hook of bone was added to the upper end. The bunch of wool or plant fibers is held in the left hand. With the right hand the fibers are drawn out several inches and the end fastened securely in the slit or hook on the top of the spindle. A whirling motion is given to the spindle on the thigh or any convenient part of the body. The spindle is then dropped, twisting the yarn, which is wound on to the upper part of the spindle. Another bunch of fibers is drawn out, the spindle is given another twirl, the yarn is wound on the spindle, and so on.

The distaff was used for holding the bunch of wool, flax, or other fibers. It was a short stick on one end of which was loosely wound the raw material. The other end of the distaff was held in the hand, under the arm or thrust in the girdle of the spinner. When held thus, one hand was left free for drawing out the fibers.[2]

A spindle containing a quantity of yarn rotates more easily, steadily, and continues longer than an empty one; hence, the next improvement was the addition of a weight called a spindle whorl at the bottom of the spindle. These whorls are discs of wood, stone, clay, or metal with a hole in the center for the spindle, which keep the spindle steady and promote its rotation. Spindle whorls appeared in the Neolithic era.

Industrial spinning:

Modern powered spinning, originally done by water or steam power but now done by electricity, is vastly faster than hand-spinning.

The spinning jenny, a multi-spool spinning wheel invented circa 1764 by James Hargreaves, dramatically reduced the amount of work needed to produce yarn, with a single worker able to work eight or more spools at once. At roughly the same time, Richard Arkwright and a team of craftsmen developed the spinning frame, which produced a stronger thread than the spinning jenny. Too large to be operated by hand, a spinning frame powered by a waterwheel became the water frame.

In 1779, Samuel Crompton combined elements of the spinning jenny and water frame to create the spinning mule. This produced a stronger thread, and was suitable for mechanisation on a grand scale. A later development, from 1828/29, was Ring spinning.

In the 20th century, new techniques including Open End spinning or rotor spinning were invented to produce yarns at rates in excess of 40 meters per second.

Characteristics of spun yarns:

Materials:

Yarn can be, and is, spun from a wide variety of materials, including natural fibers such as animal, plant, and mineral fibers, and synthetic fibers. It was probably first made from plant fibers, but animal fibers soon followed.

Twist and ply:

The direction in which the yarn is spun is called twist. Yarns are characterized as S-twist or Z-twist according to the direction of spinning (see diagram). Tightness of twist is measured in TPI (twists per inch or turns per inch)[4]

Two or more spun yarns may be twisted together or plied to form a thicker yarn. Generally, handspun single plies are spun with a Z-twist, and plying is done with an S-twist.

Plying methods:

Yarns can be made of two, three, four, or more plies, or may be used as singles without plying. Two-ply yarn can also be plied from both ends of one long strand of singles using Andean plying, in which the single is first wound around one hand in a specific manner that allows unwinding both ends at once without tangling. Navajo plying is another method of producing a three-ply yarn, in which one strand of singles is looped around itself in a manner similar to crochet and the resulting three parallel strands twisted together. This method is often used to keep colors together on singles dyed in sequential colors. Cabled yarns are usually four-ply yarns made by plying two strands of two-ply yarn together in the direction opposite to the plying direction for the two-ply yarns.

Contemporary hand spinning:

Hand-spinning is still an important skill in many traditional societies. Hobby or small scale artisan spinners spin their own yarn to control specific yarn qualities and produce yarn that is not widely available commercially.Sometimes these yarns are made available to non-spinners online and in local yarn stores. Handspinners also may spin for self-sufficiency, a sense of accomplishment, or a sense of connection to history and the land. In addition, they may take up spinning for its meditative qualities [6].

Within the recent past, many new spinners have joined into this ancient process, innovating the craft and creating new techniques. From using many new applications of dyeing before spinning, to mixing in random elements (Christmas Garland, eccentric beads, money, etc.) that would not be in a traditional yarn, to creating new techniques like coiling[7], this craft is constantly evolving and shifting.

Queen Berthe instructing girls to spin flax on spindles using distaffs

To make various yarns, besides adding random elements, spinners can vary all the same things as in a machined yarn, i.e., the fiber, the preparation, the color, the spinning technique, the direction of the twist, etc. A common misconception is yarn spun from rolags may not be as strong, but the strength of a yarn is actually based on the length of hair fiber and the degree of twist. When working with shorter hairs, such as llama or angora rabbit, the spinner may choose to integrate longer fibers, such as mohair, to prevent yarn breakage. Yarns made of shorter fibers are also given more twist than yarns of longer fibers, and are generally spun with the short draw technique.

The fiber can be dyed at any time, but is often dyed before carding or after the yarn has been spun.

Wool may be spun before or after washing, although excessive amounts of lanolin may make spinning difficult, especially when using a drop-spindle. Careless washing may cause felting. When done prior to spinning, this often leads to unusable wool fiber. In washing wool the key thing to avoid is too much agitation and fast temperature changes from hot to cold. Generally, washing is done lock by lock in warm water with dish-soap.

Techniques:

A tightly spun wool yarn made from fiber with a long staple length in it is called worsted. It is hand spun from a roving or combed top, and the fibers all lie in the same direction as the yarn. A woolen yarn, in contrast, is hand spun from a rolag, where the fibers are not as strictly aligned to the yarn created. The woolen yarn, thus, captures much more air, and makes for a softer and generally bulkier yarn. There are two main techniques to create these different yarns: short draw creates worsted yarns, and long draw creates woolen yarns. Often a spinner will spin using a combination of both techniques and thus make a semi-worsted yarn.

Spinning in the grease:

Handspinners are split, when spinning wool, as to whether it is better to spin it 'in the grease' (with lanolin still in) or after it has been washed. More traditional spinners are more willing to spin in the grease, as it is less work to wash the wool after it is in yarn form. Spinners who spin very fine yarn may also prefer to spin in the grease as it can allow them to spin finer yarns with more ease. Spinning in the grease covers the spinner's hands in lanolin and, thus, softens the spinner's hands.

Spinning in the grease only works really well if the fleece is newly sheared. After several months, the lanolin becomes sticky, which makes it harder to spin using the short draw technique, and almost impossible to spin using the long draw technique. In general, spinners using the long draw technique do not spin in the grease.

Spinners who don't spin in the grease generally buy their fibers pre-washed and carded, in the form of tow or roving. This means less work for the spinner, as they do not have to wash the lanolin out. It also means that one can spin predyed fiber, or blends of fibers, which are very hard to create when the wool is still in the grease. As machine carders cannot card wool in the grease, pre-carded yarn generally isn't spun in the grease. Some spinners, however, use spray-on lanolin-like products to get the same feel of spinning in the grease with this carded fib

Short draw spinning is used to create worsted yarns. It is spun from combed roving, sliver or wool top. The spinner keeps his/her hands very close to each other. The fibers are held, fanned out, in one hand, and the other hand pulls a small number from the mass. The twist is kept between the second hand and the wheel. There is never any twist between the two hands.

Long draw is spun from a carded rolag. The rolag is spun without much stretching of the fibers from the cylindrical configuration. This is done by allowing twist into a short section of the rolag, and then pulling back, without letting the rolag change position in your hands, until the yarn is the desired thickness. The twist will concentrate in the thinnest part of the roving; thus, when the yarn is pulled, the thicker sections with less twist will tend to thin out. Once the yarn is the desired thickness, enough twist is added to make the yarn strong. Then the yarn is wound onto the bobbin, and the process starts again.

Textile Chemistry

2010-04-04T22:57:00.000-07:00

Any of a number of textile fibers produced from chemical substances of natural origin or synthetic origin; the latter are also known as synthetic textile fibers. Among the natural sources of manufactured textile fibers are plant cellulose and protein, rubber, metals, and nonmetallic inorganics. The synthetic textile fibers are produced from organic intermediates derived from petroleum, coal, and natural gas. With the exceptions of glass and metal textile fibers, the manufactured textiles are made from very long chainlike molecules called linear polymers. These polymers may be naturally occurring (cellulose from cotton or wood pulp) or may be synthetic (polyester).

Irrespective of their chemical nature, textile fiber-forming polymers must possess the following characteristics:

(1) great length—at least 200 monomer units must be joined in a chain; (2) a high degree of intramolecular and intermolecular attraction, whether through primary chemical bonds or other attractive forces; (3) the ability to be oriented along the axis of the fiber; and (4) the ability to form well-ordered crystals or pseudocrystals. All of these parameters are sensitive to the chemical nature of the polymer and the processes of manufacture of the fiber. In turn, they establish the properties of the fiber, such as strength, flexibility, resilience, and abrasion resistance, which contribute to their usefulness in various end uses for apparel, home furnishings, and commercial and industrial applications. Only a fraction of those substances capable of forming textile fibers prove to have all of the characteristics necessary for commercial success. The fiber types of major importance in the United States are classified by composition as follows: cellulosic (composed of regenerated cellulose, cellulose diacetate, and cellulose triacetate); synthetic (composed of polyamide, polyester, polyacrylic, polyvinyl, and polyolefin resins); and inorganic (composed of glass and metal).

All of the manufactured fibers are produced according to the same principles:

(1) the textile fiber-forming material must first be made fluid; (2) the fluid is forced under pressure (extruded) through tiny holes into a medium which causes it to solidify; and (3) the solid textile fibers are further processed to obtain their optimum properties. Typically one of three procedures is used to produce fibers. In wet spinning, (for example, the production of rayon by the viscose process), the polymer is dissolved in an applicable reagent to form the fluid (dope). The fluid is then pumped through metal plates (spinnerets) containing many small holes into a liquid bath of appropriate composition. A chemical reaction between the spinning dope and the bath causes the fiber to solidify. In dry spinning, the polymer is again dissolved in an appropriate solvent and extruded through a spinneret. However, the liquid bath is replaced by a stream of warm gas (usually air) which evaporates the solvent and allows the polymer to solidify as a filament. Cellulose diacetate and triacetate are produced in this manner. In melt spinning, Nylon, polyester, and the other thermoplastic fibers are produced by melt spinning. No solvents or reagents are required since the polymer can be melted without appreciable decomposition. Thus, the fluid consists of hot molten polymer which, upon extrusion into a stream of cold air, solidifies into a filament. Depending upon the end use, filaments may be produced in various sizes ranging from finer than a human hair to thick bristles for toothbrushes. They may also be produced with different cross-sectional shapes, such as round, lobed, square, or dogbone. After extrusion, filaments are usually stretched (drawn). Drawing causes an increase in order (crystallinity) by extending the molecules of the fiber so that they pack more closely together, and orients the molecules along the longitudinal axis of the textile fiber. Higher orientation and increased crystallinity raise the strength of the fiber, decrease its stretch, and improve its elasticity. Often, the manufactured fibers are textured to improve their comfort properties. textile Fabrics made from smooth, straight filament yarns are not as comfortable as those made from yarns spun from the shorter natural fibers. Texturing introduces irregularities (crimp) along the length of the filament and leads to bulkier filament yarns which are closer to spun yarns in their performance. Advances in polymer and fiber technology have led to the development of fibers with exceptionally high temperature resistance and extremely high strength. These properties are desirable in applications such as upholstery and floor coverings in aircraft and other mass-transit vehicles, protective clothing for fire fighters and other emergency personnel, body armor for soldiers and police officers, tire cords, and industrial belting. Metallic textile fibers of silver and gold have been used for millennia to decorate fabrics. Today metallic fibers serve useful as well as decorative purposes. These fibers are formed by drawing metal wires through successively finer dies to achieve the desired diameter. Although gold and silver are the easiest to draw, modern methods have allowed the manufacture of steel, tantalum, and zirconium textile fibers. Because they are electrical conductors, metal textile fibers have been blended into textile fabrics to reduce the tendency to develop static electrical charges. Glass fibers are prepared by the melt spinning of previously formed glass marbles, and the molten filaments are drawn down to very fine dimensions. It is the fineness of the textile fibers that gives them their flexibility and allows them to be used in textiles. Unfortunately, the fibers are so stiff that when broken they can penetrate human skin. Thus, they are not well suited to use in apparel or upholstery. Glass is widely used in curtains and drapery because of its total resistance to the degrading effects of sunlight, its low cost, and its flame resistance. It provides a nonrotting, nonsettling insulating material for homes and industrial uses.textile Fiber properties include the physical, mechanical, chemical, biological, and geometrical characteristics of textile fibers. Some of the more important ones are tensile strength, elongation at break, modulus of elasticity or stiffness, fatigue under repeated stress, resilience or ability to recover from deformation, moisture absorption and wettability, electrostatic properties, friction, color, luster, density, and resistance to light, heat, weathering, abrasion, laundering, mildew, insects, chemicals, and solvents; and finally a number of geometric features, such as diameter, cross-sectional shape, and crimp. Such properties play an important part in determining whether or not the fiber can be made into a textile fabric that will be wrinkle-resistant, pleasing to the touch, comfortable, easy to clean, durable, and attractive in color, luster, drape, and general appearance. With a knowledge of textile of the physical properties of the available fibers, the textile engineer can choose the best textile fiber or best blend of several fibers to fit the intended use. The final result, however, is also dependent upon the proper choice and control of additional factors such as the yarn and fabric structure, the weave pattern, and the finishing of the cloth.

Textile Chemicals:

The enormous number of chemicals used in textile processing may be divided broadly into two categories: those intended to remain on the textile fiber, and those intended to wet or clean the textile fiber or otherwise function in some related operation. The former includes primarily dyes and finishes. The latter group consists mainly of surface-active agents, commonly known as surfactants.

Preparation:

Preparation is a term applied to a group of essentially wet chemical processes having as their object the removal of all foreign matter from the fabric. This results in a clean, absorbent substrate, ready for the subsequent coloring and finishing operations. The operations constituting preparation depend primarily on the fibers being handled. Synthetic fibers contain little or no natural impurities, so that the only materials that normally must be removed are the oils and lubricants or water-soluble sizes needed to facilitate earlier processing. This is generally accomplished by washing with water and a mild detergent capable of emulsifying the oils and waxes. On the other hand, natural fibers contain relatively high amounts of natural impurities, and in addition frequently are sized with materials presenting difficulties in removal. In the case of cotton, prolonged hot treatment with alkali, usually sodium hydroxide, and strong detergent is necessary to break down and remove the naturally occurring impurities. Special scours are necessary for cleaning such materials as wool and silk. The protein textile fibers are very sensitive to alkali and strong detergents; they are usually washed with mild soap or sulfated alcohols. After other impurities are removed from the fiber, it is usually desirable to remove any coloring material. This process is known as bleaching. By far the major bleaching agent in use is hydrogen peroxide, which is efficient in color removal, while still being considered relatively controllable and safe for use.

Mercerization:

Mercerization is a special process applied only to cotton. The textile fabric or yarn is treated with a strong sodium hydroxide solution while being held under tension. This process causes chemical and physical changes within the fiber itself, resulting in a substantial increase in luster and smoothness of the fabric, plus important improvements in dye affinity, stabilization, tensile strength, and chemical reactivity.

Coloring:

Although many textiles reach the consumer in their natural color or as a bleached white, most textiles are colored in one way or another. Coloring may be accomplished either by dyeing or printing, and the coloring materials may be either dyes or pigments.textile Dyeing essentially consists of immersing the entire fabric in the solution, so that the whole fabric becomes colored. On the other hand, printing may be considered as localized dyeing. In printing, a thickened solution of dyestuff or pigment is used. This thickened textile solution, or paste, is applied to specific areas of the fabric by means such as engraved rollers or partially porous screens. Application of steam or heat then causes the dyestuff to migrate from the dried paste into the interior of the fiber, but only in those specific areas where it has been originally applied.

Finishing:

Finishing includes a group of mechanical and chemical operations which give the textile fabric its ultimate feel and performance characteristics. Many desirable characteristics may be imparted to the textile fabric through the application of various chemical agents at this point. Softeners are used to give a desirable hand or feel to the fabric. These chemicals are generally long fatty chains, with solubilizing groups which may be cationic, nonionic, or occasionally anionic in character. They are essentially surfactants constructed so as to contain a relatively high proportion of fatty material in the molecule. Conversely, certain types of polymeric material such as polyvinyl acetate or polymerized urea formaldehyde resins are used to impart a stiff or crisp hand to a fabric. See also Polyvinyl resins; textile Urea-formaldehyde-type resins. It is in finishing that the so-called proof finishes are applied, including fire-retardant and water-repellent finishes. A fire-retardant finish is a chemical or mixture containing a high proportion of phosphorus, nitrogen, chlorine, antimony, or bromine. A truly waterproof fabric may be made by coating with rubber or vinyl, but water-repellent textile fabrics are produced by treating with hydrophobic materials such as waxes, silicones, or metallic soaps. Many other types of highly specialized treatments, such as antistatic, antibacterial, or soil-repellent finishes, may be applied to fit the fabric to a particular use.

Textile Dyeing

2010-04-04T22:46:00.000-07:00

Dyeing:

Dyeing is the process of imparting colours to a textile material in loose fibre, yarn, cloth or garment form by treatment with a dye.

Textile dyeing is concerned with organic (that is, carbon-based) compounds that can be dissolved in appropriate solvents, usually water. The dyes in solution are absorbed on the surface of the textile fibre then pass into the interior of the material by a process called diffusion.

The process of transferring the dye from solution to the fibre is called exhaustion, with 100% exhaustion meaning that there is no dye left in the dyebath solution. An important property of a dyeing is its levelness, in other words when the same depth of colour can be seen all over the material.

Another factor is good penetration, when the dye has penetrated deeply into the structure of the fibre, colouring it from the outer surface of the fibre to its interior.

Dye molecules are attracted by physical forces at the molecular level to the textile. The amount of this attraction is known as 'substantivity': the higher the substantivity the greater the attraction of the dye for the fibre.

Dye types:

For most of the thousands of years in which dyeing has been used by humans to decorate clothing, or fabrics for other uses, the primary source of dye has been nature, with the dyes being extracted from animals or plants. In the last 150 years, man has produced artificial dyes to achieve a broader range of colors, and to render the dyes more stable to resist washing and general use. Different classes of dye are used for different types of fiber and at different stages of the textile production process from loose fibers through yarn and cloth to completed garments.

Acrylic fibers are dyed with basic dyes, nylon and protein fibers such as wool and silk are dyed with acid dyes, polyester yarn is dyed with disperse dyes. Cotton is dyed with a range of dye types including vat dyes which are similar to the ancient natural dyes and modern synthetic reactive and direct dyes.

Methods:

Dyeing in Fes, Morocco.

Dyes are applied to textile goods by dyeing from dye solutions and by printing from dye pastes.

Direct application:

The term "direct dye application" stems from some dyestuff having to be either fermented as in the case of some natural dye or chemically reduced as in the case of synthetic vat and sulfur dyes before being applied. This renders the dye soluble so that it can be absorbed by the fiber since the insoluble dye has very little substantivity to the fiber. Direct dyes, a class of dyes largely for dyeing cotton, are water soluble and can be applied directly to the fiber from an aqueous solution. Most other classes of synthetic dye, other than vat and sulfur dyes, are also applied in this way.

The term may also be applied to dyeing without the use of mordants to fix the dye once it is applied. Mordants were often required to alter the hue and intensity of natural dyes and improve their color fastness. Chromium salts were until recently extensively used in dying wool with synthetic mordant dyes. These were used for economical high color fastness dark shades such as black and navy. Environmental concern has now restricted their use and they have been replaced with reactive and metal complex dyes which need no mordant.

Yarn dyeing:

There are many forms of yarn dyeing. Common forms are: at package form and at hanks form. Cotton yarns are mostly dyed at package form, and acrylic or wool yarn are dyed at hank form. In continuous filament industry, polyester or polyamide yarns are always dyed at package form, viscose rayon yarns are partly dyed at hank form because of technology

The common dyeing process of cotton yarn with reactive dyes at package form is given below in short: firstly the raw yarn is wound on a spring tube to achieve package suitable for dye penetration. Then, these softened packages are loaded on a dyeing carrier's spindle one on another. The packages are next pressed up to a desired height to achieve suitable density of packing. The carrier is then loaded on the dyeing machine and the yarn is dyed. After dyeing, the packages are unloaded from the carrier into a trolly. Next, all the packages are hydro extracted to remove the maximum amount of water. All the packages are then dried to achieve the final dyed package. At last the dyed yarn packages are packed and delivered.

Removal of dyes:

In order to remove natural or unwanted colour from material, the opposite process of bleaching is carried out.

If things go wrong in the dyeing process the dyer may be forced to remove the dye already applied by a process that normally known as stripping. This normally means destroying the dye with powerful reducing agents (sodium hydrosulphite) or oxidizing agents (Hydrogen peroxide or sodium hypochlorite). The process often risks damaging the substrate(fiber), where possible it is often less risky to dye the material a darker shade, black is often the easiest or last option.

Dye-fibre association:

In all dyeing processes the first step is to impregnate the textile material with dye solution. An important requirement is the movement of the dye into the structure of the fibre. In addition, the ability of certain types of dye to interact with the polymer material that makes up the fibre determines whether or not that type of dye is suitable for a particular fibre.

Organic dyes are classified into groups according to their ability to dye various fibres, and some of the main dye classes and their suitability for different fibres are shown opposite.

Cellulosic: Direct, reactive, vat, sulphur

Wool Acid, premetallised, reactive (some)

Polyamide Acid, premetallised, reactive (some)

Acrylic Basic, disperse (some)

Polyester Disperse

Cellulose acetate Disperse

There are broadly four types of interaction between colorant and fibre molecules: hydrogen bonding; van der Waals forces; ionic or electrostatic bonds and covalent bonds.

The first three usually act in conjunction to varying degrees in most dye classes, although depending on the colorant and the fibre and the dyeing conditions used, one of these physical forces usually predominates. Covalent forces are only present between fibres and reactive dyes.

Some of the important dye classes include:

Direct dyes:

The first direct dye was called Congo red and was introduced in 1884. It was called a direct dye because it was the first dye to become available for colouring cellulose 'directly', without the use of a mordant. Direct dyes are applied in a boiling dyebath in the presence of salt.

Advantages:

• Cheap

• Simple to apply

• Wide range of colours

• Very good fastness to light

• Disadvantages:

• Poor wet fastness

• Moderate brightness

Reactive dyes:

Developed in the 1950s, these were the first dyes produced capable of reacting chemically with the fibre (usually cellulose) under alkaline conditions. The dye thereby becomes part of the fibres, rather than merely remaining as an independent chemical entity within the fibre. Reactive dyes are applied at relatively low temperatures, with controlled amounts of salt and alkali.

Advantages:

• Simple to apply

• Wide range of bright colours

• Good fastness to light and washing

Disadvantage:

• Relatively expensive

Disperse dyes:

Disperse dyes were introduced in the 1920s to dye acetate fibres, which were otherwise undyeable, although nowadays they are mainly used for polyester fibres. They are applied at relatively high temperatures

(over 100 °C).

Acid dyes:

These are most commonly used for dyeing protein fibres such as wool and silk, the term 'acid' referring to the fact that acid or an acid-producing compound is used in the dyebath. There are different types including:

Levelling acid dyes: these are available in a range of bright colours and have good light fastness, but their wash fastness is only moderate

Milling acid dyes: these are also available in a range of bright colours and have good light and wash fastness, but are more difficult to apply correctly than levelling dyes.

The first synthetic dyes for wool were acid dyes, a class of dye that has since grown into a large, diverse, versatile and widely used group. Acid dyes are sufficiently soluble to allow direct application from an aqueous solution. Some acid dyes may also be used for coloration of other animal fibres, including silk, and also of nylon, which like protein fibres has both amide linkages and amino groups in its structure.

Garments And Clothing

2010-03-31T10:49:00.000-07:00

A feature of all modern human societies is the wearing of clothing, a category encompassing a wide variety of materials that cover the body.

The primary purpose of clothing is functional, as a protection from the elements. Clothes also enhance safety during hazardous activities such as hiking and cooking, by providing a barrier between the skin and the environment. Clothes also provide a hygienic barrier, keeping toxins away from the body and limiting the transmission of germs.

Clothing performs important social and cultural functions. A uniform, for example, may identify civil authority figures, such as police and army personnel, or it may identify team or group or even political affiliations. In most societies, norms about clothing reflect standards of modesty, religious practices and social status. Clothing may also function as a form of adornment and an expression of personal taste or style.

Throughout history, many materials have been used for clothes. Materials have ranged from leather and furs to weaved and woven materials, to elaborate and exotic natural and synthetic fabrics.

Articles carried rather than worn (such as purses, canes, and umbrellas) are normally considered fashion accessories rather than clothing, but hats and small dress sweaters can be called either clothing or accessories.[citation needed] Jewelry and eyeglasses are usually considered as accessories ,[citation needed] even though in common speech these particular items are described as being worn rather than carried.

Recent scientific research estimates that humans have been wearing clothing for as long as 650,000 years.Others claim that clothing likely originated in the neolithic age.

Functions of clothing:

A baby wearing many items of winter clothing: headband, cap, fur-lined coat, shawl and sweater

One of the primary purposes of clothing is to keep the wearer comfortable. In hot climates clothing provides protection from sunburn or wind damage, while in cold climates its thermal insulation properties are generally more important. Shelter usually reduces the functional need for clothing. For example, coats, hats, gloves, shoes, socks, and other superficial layers would normally be removed when entering or once inside a warm home, particularly if one is residing or sleeping there. Similarly, clothing has seasonal and regional aspects, so that thinner materials and fewer layers of clothing are generally worn in warmer seasons and regions than in colder ones.

Clothing at times is worn as protection from specific environmental hazards, such as insects, noxious chemicals, weapons, and contact with abrasive substances. Clothing can protect against many things that might injure the uncovered human body. Clothes act as protection from the elements, including rain, snow and wind and other weather conditions, even from the sun. Clothes also reduce the level of risk during an activity, such as work or sport. Conversely, clothing may protect the environment from the clothing wearer, as for example wearing of medical scrubs.

Humans have shown extreme inventiveness in devising clothing solutions to environmental hazards. Some examples include: space suits, air conditioned clothing, armor, diving suits, swimsuits, bee-keeper gear, motorcycle leathers, high-visibility clothing, and other pieces of protective clothing. Meanwhile, the distinction between clothing and protective equipment is not always clear-cut, since clothes designed to be fashionable will often have some protective value and clothes which are designed to be functional will often consider fashion in their design.

Origin and history of clothing:

According to archaeologists and anthropologists, the earliest clothing likely consisted of fur, leather, leaves or grass which were draped, wrapped or tied around the body. Knowledge of such clothing remains inferential, since clothing materials deteriorate quickly compared to stone, bone, shell and metal artifacts. Archeologists have identified very early sewing needles of bone and ivory from about 30,000 BC, found near Kostunica, Russia in 1988. Dyed flax fibers that could have been used in clothing have been found in a prehistoric cave in the Republic of Georgia that date back to 36,000 BP.

Scientists are still debating when people started wearing clothes. Ralf Kittler, Manfred Kayser and Mark Stone king, anthropologists at the Max Planck Institute for Evolutionary Anthropology, have conducted a genetic analysis of human body lice that suggests clothing originated quite recently, around 107,000 years ago. Body lice is an indicator of clothes-wearing, since most humans have sparse body hair, and lice thus require human clothing to survive. Their research suggests the invention of clothing may have coincided with the northward migration of modern Homo sapiens away from the warm climate of Africa, thought to have begun between 50,000 and 100,000 years ago. However, a second group of researchers using similar genetic methods estimate that clothing originated around 540,000 years ago. For now, the date of the origin of clothing remains unresolved.

Some human cultures, such as the various people of the Arctic Circle, until recently made their clothing entirely of prepared and decorated furs and skins. Other cultures have supplemented or replaced leather and skins with cloth: woven, knitted, or twined from various animal and vegetable fibers.

Although modern consumers may take the production of clothing for granted, making fabric by hand is a tedious and labor intensive process. That the textile industry was the first to be mechanized — with the powered loom — during the Industrial Revolution attests to this fact.

Different cultures have evolved various ways of creating clothes out of cloth. One approach simply involves draping the cloth. Many people wore, and still wear, garments consisting of rectangles of cloth wrapped to fit — for example, the dhoti for men and the saree for women in the Indian subcontinent, the Scottish kilt or the Javanese sarong. The clothes may simply be tied up, as is the case of the first two garments; or pins or belts hold the garments in place, as in the case of the latter two. The precious cloth remains uncut, and people of various sizes or the same person at different sizes can wear the garment.

Another approach involves cutting and sewing the cloth, but using every bit of the cloth rectangle in constructing the clothing. The tailor may cut triangular pieces from one corner of the cloth, and then add them elsewhere as gussets. Traditional European patterns for men's shirts and women's chemises take this approach.

Modern European fashion treats cloth much more prodigally, typically cutting in such a way as to leave various odd-shaped cloth remnants. Industrial sewing operations sell these as waste; home sewers may turn them into quilts.

In the thousands of years that humans have spent constructing clothing, they have created an astonishing array of styles, many of which we can reconstruct from surviving garments, photos, paintings, mosaics, etc., as well as from written descriptions. Costume history serves as a source of inspiration to current fashion designers, as well as a topic of professional interest to costumers constructing for plays, films, television, and historical reenactment.

Fur:

The use of animal fur in clothing dates to prehistoric times. It is currently associated in developed countries with expensive, designer clothing, although fur is still used by indigenous people in arctic zones and higher elevations for its warmth and protection. Once uncontroversial, it has recently been the focus of campaigns on the grounds that campaigners consider it cruel and unnecessary. PETA, along with other animal rights and animal liberation groups have called attention to fur farming and other practices they consider cruel.

Sport and activity:

Most sports and physical activities are practiced wearing special clothing, for practical, comfort or safety reasons. Common sportswear garments include short pants, T-shirts, tennis shirts, tracksuits, and trainers. Specialized garments include wet suits (for swimming, diving or surfing), salopettes (for skiing) and leotards (for gymnastics). Also, spandex materials are often used as base layers to soak up sweat. Spandex is also preferable for active sports that require form fitting garments, such as wrestling, track & field, dance, gymnastics and swimming.

Clothing maintenance:

Clothing suffers assault both from within and without. The human body sheds skin cells and body oils, and exudes sweat, urine, and feces. From the outside, sun damage, moisture, abrasion and dirt assault garments. Fleas and lice may hide in seams. Worn clothing, if not cleaned and refurbished, will itch, look scruffy, and lose functionality (as when buttons fall off and zippers fail).

In some cases, people wear an item of clothing until it falls apart. Cleaning leather presents difficulties, and bark cloth (tapa) cannot be washed without dissolving it. Owners may patch tears and rips, and brush off surface dirt, but old leather and bark clothing will always look old.

But most clothing consists of cloth, and most cloth can be laundered and mended (patching, darning, but compare felt).

Laundry, ironing, storage:

Humans have developed many specialized methods for laundering, ranging from early methods of pounding clothes against rocks in running streams, to the latest in electronic washing machines and dry cleaning (dissolving dirt in solvents other than water). Hot water washing (boiling), chemical cleaning and ironing are all traditional methods of sterilizing fabrics for hygiene purposes.

Many kinds of clothing are designed to be ironed before they are worn to remove wrinkles. Most modern formal and semi-formal clothing is in this category (for example, dress shirts and suits). Ironed clothes are believed to look clean, fresh, and neat. Much contemporary casual clothing is made of knit materials that do not readily wrinkle, and do not require ironing. Some clothing is permanent press, having been treated with a coating (such as polytetrafluoroethylene) that suppresses wrinkles and creates a smooth appearance without ironing.

Once clothes have been laundered and possibly ironed, they are usually hung on clothes hangers or folded, to keep them fresh until they are worn. Clothes are folded to allow them to be stored compactly, to prevent creasing, to preserve creases or to present them in a more pleasing manner, for instance when they are put on sale in stores.

Many kinds of clothes are folded before they are put in suitcases as preparation for travel. Other clothes, such as suits, may be hung up in special garment bags, or rolled rather than folded. Many people use their clothing as packing material around fragile items that might otherwise break in transit.

Mending:

In past times, mending was an art. A meticulous tailor or seamstress could mend rips with thread raveled from hems and seam edges so skillfully that the darn was practically invisible. When the raw material — cloth — was worth more than labor, it made sense to expend labor in saving it. Today clothing is considered a consumable item. Mass-manufactured clothing is less expensive than the labor required to repair it. Many people will buy a new piece of clothing rather than expend time mending. The thrifty still replace zippers and buttons and sew up ripped hems.

Preparing Warp and Weft for Weaving

2010-03-30T11:55:00.000-07:00

Preparing Warp and Weft for Weaving:

The power loom is only one of a series of machines which revolutionized weaving. Although early inventors of the power loom did much to perfect its various movements, the commercial results were disappointing, chiefly because means had not been devised for preparing warp and weft in a suitable manner for such a machine. William Radcliffe, of Stockport, perceived these shortcomings, and concluded that, by division of labour, weaving could be brought into line with, the then recently invented, spinning machinery. He, therefore, set himself the task of solving the problems involved, and by inventing the beam warper, the dressing sizing machine, the shuttle tongue, and the pin cop, he enabled the power loom to become a factor in the textile industry. The term preparation embraces winding, warping, sizing, Yorkshire dressing, drawing-in, twisting and occasionally other operations.

Weft Winding:

Weft yarns invariably receive simpler treatment than warp yarns; in many cases none at all. Cops and ring spools pass direct to the loom unless their dimensions are unsuited to the shuttles, in which case they, together with wefts bleached or dyed in hanks or used in a saturated condition, require winding upon pirns, or into cops of suitable sizes. Pirn winders differ greatly in construction, but the majority are furnished with conical shapers, consisting either of slip cups, or of cone rollers mounted upon studs. A pirn, whose head is coned to fit inside a shaper, is slipped over a spindle, and both are passed, either vertically or horizontally, through a shaper; the basal end of the spindle being flattened to enter a rectangular hole in a wharve which is driven from a central tin drum. A thread is attached to a rotating pirn, and a vibrating guider leads it to and fro inside the shaper. Both spindle and pirn recede from the shaper until the pirn is full, when they become stationary. Hanks are carried by ryces, and cops and ring spools by skewers. Cop winders are chiefly used for coarse yarns, which they coil upon bare spindles. By this means a greater length of weft can be placed in a shuttle than when pirns are used.

Warping:

The number of longitudinal threads in a web vary according to their closeness and its breadth. It is the function of a warper to provide a sufficient number of parallel threads for a web, all of equal length, and to retain their parallelism. Warpers are of three types, viz. mill, beam and sectional.

Mill warping is the oldest type now in extensive use. A mill warper has a creel in which from so to upwards of 300 bobbins or cheeses, are supported horizontally upon pegs, and the mill has a vertical axis which carries three wheels, upon whose rims vertical staves are fixed about 1 ft. apart to form a reel, from 5 to upwards of 20 yds. in circumference. The threads from the creel are threaded in succession through leasing needles, then passed in groups of four to twenty threads between runners, and, finally, fastened by a peg to the mill staves. The needles are mounted alternately in two frames which may be moved up inclined planes; one to elevate odd threads, the other even ones, and both separations thus formed are retained upon separate pegs; this is the lease which enables a weaver to readily fix the position of a broken thread. As the mill rotates the threads form a tape about I in. wide, and the leasing apparatus slides down a post to coil the threads spirally upon the reel. When the full length of warp has been made the mill is stopped, a half beer lease is picked by hand from the divisions formed by the runners, and also retained upon pegs. The mill next reverses its direction of rotation, and as the leasing apparatus ascends the threads are folded back upon themselves. Hence, if a reel is 20 yds. in circumference, and zoo threads are in use to make a warp 600 yds. long, and containing 2000 threads, the reel will make 30 revolutions (600 4-20 =30) also 10 reversals, for at each reversal 200 additional threads will be added (2000 +200 = 10). When a warp is complete, strings are passed through the leases, and it is coiled into a ball, loosely linked into a chain, or dropped into a sheet. If a mill has its axis horizontal the leasing apparatus must slide horizontally.

Winding on Frame. - After a ball warp has been bleached, dyed or sized, the half beers are laid amongst the teeth of a coarse comb to open out the threads to the necessary breadth, in which condition they are coiled upon a loom beam.

Beam warping is the system most extensively used in the cotton trade. The creels for these machines have an average capacity of about 600 bobbins, and are often V-shaped in plan. In each leg of the V the bobbins are arranged in tiers of 16 to 20, and row behind row. The threads are drawn separately between the dents of an adjustable reed, then under and over a series of rollers; from here they are dropped amongst the teeth of an adjustable comb and led down to a warpers beam, which rests upon the surface of a drum. As the drum rotates the threads are drawn from the bobbins and wrapped in even coils upon the beam. On most of these machines mechanism is attached for arresting motion on the fracture of a thread, and also for accurately measuring and recording the lengths of warp made. When full, a warpers beam holds threads of much greater length than are needed for any warp, but they are insufficient in number. Thus: If 500 threads are in use, and warps of the above-named particulars are required, four similar beams must be filled (2000 + 500 = 4) and the threads from all are subsequently united. The chief parts of a beam warper may be used as a substitute for a mill warper, provided that mechanism be employed to contract the threads to the form of a loose rope and coil them into a cylindrical ball, which will be subsequently treated as a mill warp. Or, one of these warpers may be furnished with parts which, when the threads are roped, links them loosely into a chain.

Sectional warping is chiefly employed for coloured threads and its outstanding features consist in contracting the threads to form a ribbon of from 3 in. to 12 in. wide. This ribbon is coiled upon a block placed between flanges, and when completed is set aside until a sufficient number of similar sections have been made; after which they are slipped upon a shaft and by endlong pressure con - verted into a compact mass. All the threads are then collected and transferred in the form of a sheet to a loom beam; each section contributing its own width to that of the warp. Sectional warps are also made upon horizontal mills by superposing the coils of a ,ibbon of yarn upon a portion of the staves. When the first section is formed a second is wound against it, and the operation continued until all the sections have been made; after which the yarn is run upon a loom beam.

Yorkshire dressing is used to make striped warps from balled warps which have been dyed in different colours. The operation is as follows: The requisite number of threads of any colour is split from a uniformly dyed ball and set aside until warps of the remaining colours have been similarly treated. The split sections from the several balls collectively contain as many threads as are needed for a warp, but those threads have still to be placed in their proper sequence. This is done by drawing them in groups of two or four between the dents of a reed to a predetermined colour scheme, then all are attached to a loom beam which is supported in a frame. The beam is rotated by stepped cones and gearing, and winds the threads upon itself. But in order to hold the threads taut they are passed between weighted rollers and deflected by bars arranged ladder - wise; in passing from one part of the machine to another they are gradually opened out to the width of the beam.

Sizing:

In cases where single yarns are made from short fibrous materials, smooth surfaces are obtained by laying the outstanding ends of fibres upon the thread, and fastening the fibres together to impart sufficient strength to resist the strains of weaving. This is accomplished either by coating a thread or by saturating it with an adhesive paste. In hand-loom days the paste was applied by brushes to successive stretches of warp while in a loom. But with the advent of mechanical weaving it was found necessary to size a warp before placing it in a loom. Two systems were evolved, the one invented by William Radcliffe sizes, dries and beams a warp in one operation, the yarn is made to pass in the form of a sheet between a pair of rollers, the lower one being partly immersed in warm size. In rotating this roller carries upon its surface a film of size which it deposits upon the threads, while, by pr,essure, the upper roller distributes the size evenly. Brushes acting automatically smooth down the loose fibres and complete the distribution of size. As the yarn advances it is separated by reeds and lease rods, so that in passing over steam chests and fans the moisture contained in the threads may be quickly evaporated. This machine is a duplex one, for the warpers beams are divided into two sets and placed at opposite ends of the machine. Both halves receive similar treatment as they move to the centre, where the loom beam is placed.

The Ball Warp Sizer. - While efforts were being made to perfect Radcliffe's dressing machine a system of sizing ball warps was being gradually evolved and this system is still largely employed. The machine consists of a long trough, inside which a series of rollers are fitted, either in one horizontal plane or alternately in two horizontal planes; but over the front end of the trough a pair of squeezing rollers are mounted. The trough contains size, which is maintained at a boiling temperature and in sufficient quantity to submerge the rollers. Two warps, in the form of loose tapes, may be simultaneously led over, under and between the rollers. As the warps advance the threads become saturated with size, and the squeezing rollers press out all but a predetermined percentage, the latter being regulated by varying the pressure of the upper roller upon the lower one. If more size be required than can be put into the threads during one passage through the machine, they may be similarly treated a second time. This process does not lay all the loose fibres, but the threads remain elastic. After sizing, the warps are passed backward and forward, and over and under, a set of steam-heated cylinders by which the moisture contained in the threads is evaporated; they are next either reballed, or wound upon a loom beam.

Slasher Sizing:

For sizing cotton yarns Radcliffe's dressing machine has to a large extent been displaced by the slasher, but in some branches of the textile industry it is still retained under various modifications. In a slasher the threads from a number of warping beams are first combined into one sheet, then plunged into a trough filled ' with size which is kept at a boiling temperature by perforated steam pipes; and next squeezed between two pairs of rollers mounted in the trough. The under surfaces of the sizing rollers are in the size, but the upper squeezing rollers are covered with flannel, and rest by gravitation upon the lower ones. On leaving the size trough the sheet of yarn almost encircles two steam-heated cylinders whose diameters are respectively about 6 ft. and 4 ft.; these quickly expel moisture from the yarn, but so much heat is generated that fans have to be employed to throw cool air` amongst the threads. The yarn is next measured, passed above and below rods which separate threads that have been fastened together by size, smeared with piece marks, and coiled upon a loom beam by means of a slipping friction gear. The last-named is employed so that the surface speed of winding shall not be affected by the increasing diameter of the loom beam. By means of mechanism which greatly reduces the velocities of the moving parts, much necessary labour may be performed without actually stopping the machine; this relieves the yarn of strain, and gives better sizing, yet slashed warps are less elastic than dressed, or balled sized ones, and they lack the smoothness of dressed warps.

Hank sizing is chiefly, but not exclusively, employed for bleached and coloured yarns. Machines for doing this work consist of a tank which contains size, flanged revolving rollers and two hooks. One hook is made to rotate a definite number of times in one direction, then an equal number the reverse way; the other has a weight suspended from its outer end and can be made to slide in and out. Size in the tank is kept at the required temperature by steam pipes, and " doles " of hanks are suspended from the rollers with about one-third their length immersed in size. As the hanks rotate all parts of the yarn enter the size, and when sufficiently treated they are removed from the rollers to the hooks where they are twisted to wring out excess, and force in required size. If sufficient size has not been added by one treatment, when untwisted, the wrung-out hanks are passed to a similar machine containing paste of greater density than the first there to be again treated; if necessary this may be followed by a third passage. On the completion of sizing the hanks are removed either to a drying stove or a drying machine. If to the former, they are suspended from fixed, horizontal poles in a specially heated and ventilated chamber. If to the latter, loose poles containing hanks are dropped into recesses in endless chains, and slowly carried through a large, heated and ventilated box, being partially rotated the while. On reaching the front of the box they are removed, brushed and made up into bundles. After which the yarn is wound, warped and transferred to a loom beam.

Drawing-in, or entering, is the operation of passing warp threads through the eyes of a shedding harness, in a sequence determined by the nature of the pattern to be produced, and the order of lifting the several parts. It is effected by passing a hook through each harness eye in succession, and each time a thread is placed in the hook by an attendant, it is drawn into an eye by the withdrawal of the hook.

Twisting or looming consists in twisting, between the finger and thumb, the ends of a new warp separately upon those of an old one, the remains of which are still in the eyes of the shedding harness. The twisted portions adhere sufficiently to permit of all being drawn through the eyes simultaneously.

The Power Loom. - Little is known of the attempts made before the beginning of the 17th century to control all parts of a loom from one centre, but it is certain the practical outcome was inconsiderable. In the year 1661, a loom was set up in Danzig, for which a claim was made that it could weave four or six webs at a time without human aid, and be worked night and day; this was probably a ribbon loom. In order to prevent such a machine from injuring the poor people, the authorities in Poland suppressed it, and privately strangled or drowned the inventor. M. de Gennes, a French naval officer, in 1678 invented a machine whose chief features consisted in controlling the healds by cams, the batten by cams and springs and the shuttle by a carrier. From 1678 to 1745 little of importance appears to have been done for the mechanical weaving of broadcloth. But in the last-named year M. Vaucanson constructed a very ingenious, self - acting loom, on which the forerunner of the Jacquard machine was mounted; he also adopted de Gennes's shuttle carrier. All early attempts to employ mechanical motive power for weaving failed, largely because inventors did not realize that success could only be reached through revolution. Mechanical preparing and spinning machinery had first to be invented, steam was needed for motive power, and the industry required reorganization, which included the abolition of home labour and the introduction of the factory system.

During the last quarter of the 18th century it was generally believed that, on the expiry of Arkwright's patents, so many spinning mills would be erected as to render it impossible to consume at home the yarns thus produced, and to export them would destroy the weaving industry. Many manufacturers also maintained it to be impossible to devise machinery which would bring the production of cloth up to that of yarn. It was as a protest against the last-named assertions that Dr Edmund Cartwright, a clergyman of the church of England, turned his attention to mechanical weaving. More fortunate than his predecessors, he attacked the problem after much initial work had been done, especially that relating to mechanical spinning and the factory system, for without these no power loom could succeed. In 1785 Dr Cartwright patented his first power loom, but it proved to be valueless. In the following year, however, he patented another loom which has served as the model for later in - ventors to work upon. He was conscious that for a mechanically driven loom to become a commercial success, either one person would have to attend several machines, or each machine must have a greater productive capacity than one manually controlled. The thought and ingenuity bestowed by Dr Cartwright upon the realization of his ideal were remarkable. He added parts which no loom, whether worked manually or mechanically, had previously been provided with, namely, a positive let-off motion, warp and weft stop motions, and sizing the warp while the loom was in action. With this machine he commenced, at Doncaster, to manufacture fabrics, and by so doing discovered many of its shortcomings, and these he attempted to remedy: by introducing a crank and eccentrical wheels to actuate the batten differentially; by improving the picking mechanism; by a device for stopping the loom when a shuttle failed to enter a shuttle box; by preventing a shuttle from rebounding when in a box; and by stretching the cloth with temples that acted automatically. In 1792 Dr Cartwright obtained his last patent for weaving machinery; this provided the loom with multiple shuttle boxes for weaving checks and cross stripes. But all his efforts were unavailing; it became apparent that no mechanism, however perfect, could succeed so long as warps continued to be sized while a loom was stationary. His plans for sizing them while a loom was in operation, and also before being placed in a loom, both failed. Still, provided continuity of action could be attained, the position of the power loom was assured, and means for the attainment of this end were supplied in 1803, by William Radcliffe, and his assistant Thomas Johnson, by their inventions of the beam warper, and the dressing sizing machine.

For upwards of thirty years the power loom was worked under numerous difficulties; the mechanism was imperfect, as were also organization, and the preparatory processes. Textile workers were unused to automatic machinery, and many who had been accustomed to labour in their own homes refused employment in mills, owing to dislike of the factory system and the long hours of toil which it entailed, that spinners and manufacturers were compelled to procure assistants from workhouses; this rendered mill life more distasteful than it otherwise would have been to hand spinners and weavers. Their resentment led them to destroy machinery, to burn down mills, to ill-use mill workers and to blame the power loom for the distress occasioned by war and political disturbances. Yet improvements in every branch of the textile industry followed each other in quick successions, and the loom slowly assumed its present shape. By using iron instead of wood in its construction, and centring the batten, or slay, below instead of above the warp line, the power loom became more compact than the hand-loom.

Motion is communicated to all the working parts from a main shaft A (fig. 28), upon which two cranks are bent to cause the slay B to oscillate; by toothed wheels this shaft, drives a second shaft, C, at half its own speed. For plain weaving four tappets are fixed upon the second shaft, two, D, for moving the shuttle to and fro, and two others, E, for moving the healds, L, up and down through the medium of treadles M, M. For other schemes of weaving shedding tappets are more numerous, and are either loosely mounted upon the second shaft, or fixed upon a separate one. In either event FIG. 28. - Vertical Section of a Power Loom.

they are driven by additional gearing, for the revolutions of the tappets to those of the crank shaft must be as one is to the number of picks in the repeat of the pattern to be woven. Also, when two or more shuttles are driven successively from the same side of a loom, if the picking tappets rotate with the second shaft, those tappets must be free to slide axially in order to keep one out of action so long as the other is required to act. The warp beam F is often put under the control of chains instead of ropes, as used in hand looms, and the chains are attached to adjustably weighted levers, G, whereby the effectiveness of the weights may be varied at pleasure. In the manufacture of heavy fabrics, however, it may be necessary to deliver the warp by positive gearing, which is either connected, or otherwise, to the taking-up motion. The cloth is drawn forward regularly as it is manufactured by passing it over the rough surface of a roller, I, and imparting to the roller an intermittent motion each time a pick of weft is beaten home. This motion is derived from the oscillating slay, and is communicated through a train of wheels. The loom is stopped when the weft fails by a fork-and-grid stop motion, which depends for its action on the lightly balanced prongs of a fork, N. These prongs come in contact with the weft, between the selvage of the web and the shuttle box each time the shuttle is shot to the side at which the apparatus is fixed. If the prongs meet no thread they are not depressed, and being unmoved a connexion is formed with a vibrating lever, J; the latter draws the fork forward, and with it a second lever 0, by which the loom is stopped. On the other hand, if the prongs are tilted, the loom continues in action. If more than one shuttle is used it may be necessary to feel for each, instead of alternate threads of weft. In such cases a fork is placed beneath the centre of the cloth and lifted above a moving shuttle; if in falling it meets with weft it is arrested, and the loom continues in motion, but if the weft is absent the prongs fall far enough beneath the shuttle race for a stop to act upon a lever and bring the loom to a stand. To prevent a complete wreck of the warp it is essential to arrest the loom when a shuttle fails to reach its appointed box. For this purpose there are two devices, which are known respectively as fast and loose reed stop motions. The first was invented in 1796 by Robert Miller, and its action depends upon the shuttle, as it enters a box, raising two blades, K, which if left down would strike against stops, and so disengage the driving gear. The second was invented in 1834 by W. H. Hornby and William Kenworthy; i; it is an appliance for liberating the lower part of a reed when a shuttle remains in the warp, thus relieving it, for the time being, of its function of beating up the weft. On the release of a reed from the motion of the slay, a dagger stops the loom. Temples must keep a fabric distended to the breadth of the warp in the reed, and be selfadjusting. This is usually accomplished by small rollers whose surfaces are covered with fine, closely set points. The rollers are placed near the selvages of a web which is prevented from contracting widthwise by being drawn tightly over the points.

Looms are varied in details to suit different kinds of work, but as a rule fabrics figured with small patterns are provided with healds for shedding as at L, while those with large patterns are provided with the Jacquard and its harness. Healds may be operated either by tappets or dobbies, but the range of usefulness in tappets is generally reached with twelve shafts of healds and with patterns having sixteen picks to a repeat; where they are unsuitable for heald shedding a dobby is used. A dobby may resemble, in con - struction and action, a small Jacquard; if so the selection of healds that rise and fall for any pick is made by cards. In other types of dobbies the selection is frequently made by lags, into which pegs are inserted to pattern in the same manner that cards are perforated. By acting upon levers the pegs bring corresponding hooks into contact with oscillating grille bars, and these lift the required heald shafts. Such machines are made single and double acting, and some have rollers in place of pegs to form a pattern. When multiple shuttles are required for power looms one of two types is selected, namely, drop or rotating boxes; the former are applicable to either light or heavy looms, but the latter are chiefly confined to light looms. As previously stated, Robert Kay invented drop boxes in 1760, but they were not successfully applied to the power loom until 1845, when Squire Diggle patented a simple device for operating them automatically. Since his time many other methods have been introduced, the most successful of these being operated indirectly from the shedding motion. Revolving boxes were patented in 1843 by Luke Smith. They consist in mounting a series of shuttles in chambers formed in the periphery of a cylinder, and in moving the cylinder far enough, in each direction, to bring the required shuttle in line with the picker.

Automatic Weft Supply:

Many devices have been added to power looms with a view to reduce stoppages, amongst which those for the automatic supply of weft are probably the most important. These efforts originated with Charles Parker, who, in 1840, obtained the first patent, but no marked success was achieved until 1894, when J. H. Northrop patented a cop changer. By his plan a cylindrical hopper, placed over one shuttle box, is charged with cops or pirns. At the instant fresh weft becomes necessary the lowest cop in the hopper is pressed into a shuttle from above, the spent one is pressed out from beneath, and the new weft is led into the shuttle eye, while the loom is moving at its normal speed. The mechanism is controlled by the weft fork, or by a feeler which acts when only a predetermined quantity of weft remains inside a shuttle. Many inventions are designed to eject an empty shuttle and intro - duce a full one; others change a cop, but differ in construction and action from the Northrop, yet, at the time of writing, they have not been so successful as the last-named. By relieving a weaver of the labour of withdrawing, filling, threading and inserting shuttles it was seen that a large increase might be made in the number of looms allotted to one weaver, provided suitable mechanism could be devised for stopping a loom on the failure of a warp thread.

Warp Stopping Motions date from 1786, when Dr Cartwright suspended an independent detector from each warp thread until a fracture occurred, at which time a detector fell into the path of a vibrator and the loom was arrested. The demand for warp stop motions was, however, small until automatic weft supply mechanisms were adopted. The majority of those devices now in use are con - structed upon Dr Cartwright's lines, but some are so attached to wire healds that, at one position in every shed, an unbroken thread supports both heald and detector until a thread fails, when a de - tector is engaged by a vibrator, and the driving mechanism is dis - located. In other warp stop motions pairs of threads are crossed between the lease rods, and a wire passed between them is held forward by the crossed threads until one breaks; the wire then springs back, makes contact with a metal bar, and electro-mechanical connexions stop the loom.

Smallware Looms:

A loom, which was for a long period operated manually, but to which mechanical power could be applied, was brought into use more than a century before Dr Cartwright's in - vention. It was known as the Dutch engine loom, and was designed to weave from eight to upwards of forty tapes or ribbons simultane - ously. This machine may be regarded as a series of looms mounted in one frame, each having a complete set of parts, and as the first practical effort to connect and control all the motions of weaving from one centre. The place and date of its invention are uncertain; but it is known that in some districts its use was entirely prohibited, in others it was strictly limited, and that it was worked in Holland about 1620. In England the first patent was obtained by John Kay and John Snell, in 1745, for additions which enabled it to be worked by hand, by water, or other force, and in 1760 John Snell appears to have added the draw harness for weaving flowered ribbons. In 1765 a factory in Manchester was filled with ribbon looms which were either invented by M. Vaucanson, or Kay and Snell, but one weaver could only attend to one machine. When worked by hand it was known as the bar loom, because the weaver oscillated by hand a horizontal bar that set in motion all parts of the machine. The shuttles and reeds are actuated from the batten, the former originally by pegs, but later by a rack and pinion arrangement, which in action shoot the shuttles simultaneously across a web, to the right and left alternately, each into the place vacated by its next neighbour. One small warp beam is required for each web, but tappets, dobbies, or Jacquards are available for dividing the threads. Where differ - ently coloured wefts are needed in one web the shuttles are mounted in tiers and all raised or lowered at once to bring the proper colour in line with the shed.

In Swivel Weaving similar shuttles are added to the battens of broad looms in order to diaper small figure effects, in different colours or materials, over the surface of broad webs.

Pile Weaving. - Looms for weaving piled fabrics differ in certain important respects from those employed for ordinary weaving; they are also made to differ from each other to suit the type of fabric to be manufactured, as, for example, double and single, plain and figured, textures.

In Double Pile Looms the special features are those that control the pile threads, and those that sever the vertical lines of pile. Two ground warps are requisite, and unless they are kept a uniform distance apart the piled effects will be irregular. For plain goods the pile threads are wound upon two or more beams, and, as they move from web to web, cloth-covered rollers deliver them in fixed lengths. Meanwhile, a shuttle passes twice in succession through each ground warp, and the pile threads in moving above or beneath the wefts are bound securely. Both fabrics are furnished with taking-up rollers which draw the pieces apart and so stretch the uniting pile in front of a knife, which severs it, thus forming two pieces at once. A knife may consist of a short blade that merely moves to and fro across the webs, or of a disk mounted upon a spindle, which, in moving from side to side, revolves; in either case it is automatically sharpened. But if a knife is longer than the breadth of a fabric it receives only a slight lateral movement, and must be periodically removed for sharpening. In plain and printed goods healds control all the warps; but in figured goods, other than those made from printed warps, a Jacquard is needed to lift, and a creel to hold, the pile threads.

Single Pile Looms:

The chief feature which renders most single pile looms dissimilar from others is the mechanism by which wires are woven upon, and withdrawn automatically from, a ground texture. Wires are of two kinds, namely, without and with knives; the former, being flattened and somewhat pointed, are woven above the weft of a ground texture, but beneath the pile, hence, by with - drawing them, looped pile is formed. A wire terminating in a knife with a sloping blade, on being withdrawn, cuts the pile and produces a brush-like surface. The mechanism for operating the wires is placed at one end of a loom and consists of an arm which moves in and out; at each inward movement a wire is inserted, and at each outward movement one is withdrawn. In weaving tapestry carpets, and certain other fabrics, a wire and a shuttle move simultaneously, but a shuttle passes through the ground warp, while a wire passes beneath the pile. After several wires have been woven upon the ground texture the one first inserted is withdrawn by the vibrating arm, and at the next inward movement the same wire enters the warp near the reed, where it is beaten up with the weft, and, from this point, the operation is continuous. Tapestry carpets require three warps, one for the ground texture, a second, or stuffing warp, to give bulk and elasticity to the tread, and a third to form the pile. The last named is printed upon a large drum, thread by thread to the colour scheme of the design, then, when the colours have been fixed, and the threads accurately placed, they are wound upon a beam, and all the warps are operated by healds. For figured velvets, and Brussels and Wilton carpets, the pile warp beam is replaced by a creel, in order that each thread of pile may be wound upon a bobbin and separately tensioned. This is essential, because, in the weaving of a design, it is probable that no two threads of pile will be required in equal lengths. Creels are made in sections called frames, each of which usually carries as many bobbins as there are loops of pile across a web, and the number of sections equal the number of colours. In weaving these fabrics healds are used to govern the ground warp, but a Jacquard is needed for the pile. It must form two sheds, the lower one to receive a shuttle, the upper one to make a selection of threads beneath which the wire is to pass.

Terry Looms:

Looms for weaving piled textures, of the Turkish towel type, have the reed placed under the control of parts that prevent it from advancing its full distance for two picks out of every as those of the present day, with dragons, phoenixes, mystical bird forms, flowers and fruits.' At that time even Egypt, Assyria or Babylonia, Greece and Rome, seem to have been only learning of the fact that there was such a material as silk.' Their shuttle-weaving had been and was then concerned with spun wool and flax and possibly some cotton, whilst the ornamentation of their textiles, although sparkling on occasion with golden threads, was done apparently not by shuttle-weaving but by either embroidery or a sort of compromise between darning and weaving from which tapestry weaving descended (see Tapestry). The range of their colours was limited, reds, purples and yellows being the chief; and their shuttle-weaving was principally concerned with plain stuffs, and in a much smaller degree with striped, spotted and chequered fabrics. Remains of these, whether made by Egyptians thousands of years B.C., by Scandinavians of the early Bronze Age, by lake dwellers, by Aztecs or Peruvians long before the Spanish Conquest, display little if any technical difference when compared with those woven by nomads in Asia, hill tribes in India and natives in Central Africa and islands of the Pacific. Such ornamental effect as is seen in them depends upon the repetition of stripes or very simple crossing forms, still this principle of repetition is a prominent factor in more intricate designs which are shuttlewoven in broad looms and lengths of stuff.

The world's apparent indebtedness to the Chinese for knowledge of figured shuttle-weaving leads to some consideration of their early overland commerce westwards. About 200 B.C. during the Han Dynasty Chinese trade had extended beyond inner Asia to the confines of the Graeco-Parthian empire, then at its zenith, and the protection of the route by which the Seres (Chinese) sent their merchandise was fully recognized as a matter of importance. Seventy years later the emperor of China sent a certain Chang Kien on a mission to the Indo-Scythians; and according to his records the people as far west as Bactria (adjacent to the Graeco-Parthian territory) were knowing traders, and amongst other things under - stood the preparation of silk. Chinese weavings had for some time been coming into Persia, and doubtless instigated the more skilled weavers there to adapt their shuttle looms in course of time to the. weaving of stuffs with greater variety of effects than had been hitherto obtained by them; and into Persian designs were intro - duced details taken not only from Chinese textiles, but also from sculptured, embroidered and other ornament of Graeco-Parthian and earlier Babylonian styles. In A.D. 97 Chinese enterprise in still furthering their trade relations with the Far West is at least sug - gested by the fact that envoys from the emperor of China to Rome actually reached the eastern shores of the Mediterranean, but turned back frightened by the Parthian accounts of the terrors of the sea voyage.

Early in the 3rd century A.D. Heliogabalus is reputed to have been amongst the first of the Roman emperors to wear garments entirely of silk (holosericum), which, if figured (as is not unlikely), were probably of Syrian or Persian manufacture. Sidonius Apollinaris (5th century) writes of Persian patterned stuffs, - " Bring forth brilliant cushions and stuffs on which, produced by a miracle of art, we behold the fierce Parthian with his head turned back on a prancing steed; now escaping, now returning to hurl his spear, by turns fleeing from and putting to flight wild animals whom he pursues " - a description quite appropriate to such silk weaving as that in fig. 33. A number of kindred pieces have been recovered of late years from Egyptian burial-places of the Roman period. The Persians of the Sassanian dynasty (3rd to 7th century) traded in silks with Romans and Byzantines; King Chosroes (about 570) encouraged the trade, and ornamental weaving seems to have been an industry of some standing at Bagdad and other towns north, east and south, e.g. Hamadan, Kazvin Kashan, Yezd Persepolis, &c. To the north - west of Persia and north of Syria lay the Byzantine region of Anatolia (now Asia Minor), some towns in which became noted for their fine weavings: the mass of the population there was well off in the 6th century, the country highly cultivated and prosperous, and justice fairly administered,' thus affording favourable conditions for an industry like ornamental weaving, which had been and was prospering in neighbouring Syrian districts.

Preparation To Yarn Manufacture

2010-03-30T11:49:00.000-07:00

Yarn:

Yarn is a long continuous length of interlocked fibres, suitable for use in the production of textiles, sewing, crocheting, knitting, weaving, embroidery and ropemaking. Thread is a type of yarn intended for sewing by hand or machine. Modern manufactured sewing threads may be finished with wax or other lubricants to withstand the stresses involved in sewing.Embroidery threads are yarns specifically designed for hand or machine embroidery.

Structure:

Spun yarn is made by twisting or otherwise bonding staple fibers together to make a cohesive thread.Twisting fibers into yarn in the process called spinning can be dated back to the Upper Paleolithic, and yarn spinning was one of the very first processes to be industrialized. Spun yarns may contain a single type of fiber, or be a blend of various types. Combining synthetic fibers (which have high strength, artificial lustre, and fire retardant qualities) with natural fibers (which have good water absorbance and skin comforting qualities) is very common. The most widely used blends are cotton-polyester and wool-acrylic fiber blends. Blends of different natural fibers are common too, especially with more expensive fibers such as angora and cashmere. Yarns are made up of a number of plies, each ply being a single spun yarn. These single plies of yarn are twisted in the opposite direction (plied) together to make a thicker yarn. Depending on the direction of this final twist, the yarn will be known as s-twist or z-twist. For a single ply, the direction of the final twist is the same as its original twist. Filament yarn consists of filament fibers twisted together. Thicker monofilaments are typically used for industrial purposes rather than fabric production or decoration. Silk is a natural filament, and synthetic filament yarns are used to produce silk-like effects. Texturized yarns are made by a process of air texturizing (sometimes referred to as taslanizing), which combines multiple filament yarns into a yarn with some of the characteristics of spun yarns.

Measurement:

Craft yarns:

Cat with a ball of mixed-color yarn. Spool of all purpose sewing thread, closeup shows texture of 2-ply Z-twist mercerized cotton with polyester core. Yarn drying after being dyed in the early American tradition, at Conner Prairie living history museum. Yarn quantities are usually measured by weight in ounces or grams. In the United States, Canada and Europe, balls of yarn for handcrafts are sold by weight. Common sizes include 25g, 50g, and 100g skeins. Some companies also primarily measure in ounces with common sizes being three-ounce, four-ounce, six-ounce, and eight-ounce skeins. These measurements are taken at a standard temperature and humidity, because yarn can absorb moisture from the air. The actual length of the yarn contained in a ball or skein can vary due to the inherent heaviness of the fiber and the thickness of the strand; for instance, a 50 g skein of lace weight mohair may contain several hundred meters, while a 50 g skein of bulky wool may contain only 60 meters. There are several thicknesses of yarn, also referred to as weight. This is not to be confused with the measurement of weight listed above. The Craft Yarn Council of America is making an effort to promote a standardized industry system for measuring this, numbering the weights from 1 (finest) to 6 (heaviest). Some of the names for the various weights of yarn from finest to thickest are called lace, fingering, sock, sport, double-knit (or DK), worsted, aran, bulky, and super-bulky. This naming convention is more descriptive than precise; fiber artists disagree about where on the continuum each lies, and the precise relationships between the sizes. A more precise measurement of yarn weight, often used by weavers, is wraps per inch (wpi). The yarn is wrapped snugly around a ruler and the number of wraps that fit in an inch are counted. Labels on yarn for handcrafts often include information on gauge, known in the UK as tension, which is a measurement of how many stitches and rows are produced per inch or per centimeter on a specified size of knitting needle or crochet hook. The proposed standardization uses a four-by-four inch/ten-by-ten centimeter knitted or crocheted square, with the resultant number of stitches across and rows high made by the suggested tools on the label to determine the gauge. In Europe textile engineers often use the unit tex, which is the weight in grams of a kilometer of yarn, or decitex, which is a finer measurement corresponding to the weight in grams of 10 kilometers of yarn. Many other units have been used over time by different industries.

Thread:

Most types of embroidery thread come in a single size or weight; an exception is pearl or perle cotton, which comes in three weights, No. 3 (heaviest), No. 5, and No. 8 (finest).

Color:

Yarn may be used undyed, or may be colored with natural or artificial dyes. Most yarns have a single uniform hue, but there is also a wide selection of variegated yarns: • heathered or tweed: yarn with flecks of different colored fiber • ombre: variegated yarn with light and dark shades of a single hue • multi-colored: variegated yarn with two or more distinct hues (a "parrot colorway" might have green, yellow and red) • self-striping: yarn dyed with lengths of color that will automatically create stripes in a knitted or crocheted object • marled: yarn made from strands of different-colored yarn twisted together, sometimes in closely-related hues

OBJECT OF GINNING:

The primary object of the ginning consists in separating the fibres from the seed, and a Perfect ginning operation would be Performed if the separation of fibres from seed was effected without the slightest injury to either seeds or to the fiber.

DIFFERENT TYPES OF GIN:

Previous to the introduction of Modern Machinery, ginning was performed by hand or by machines of a primitive character such as the "Foot Roller" and its improvement the "Churka". As the cotton industry developed, greater production than these were capable of was necessary, and machines driven by power were introduced. Numerous forms of gins have been tried, but at the present time only three are used to any large extent. They are

1. KNIFE ROLLER GIN

2. SAW GIN

3. THREE TYPES OF MACARTHY GIN I.

Single acting macarthy gin. ii. Double acting macarthy gin iii. Double roller macarthy gin.

KNIFE ROLLER GIN:

Object: To separate the fibres from seed The constructional detail of the machine is clearly shown in fig. The seed cotton is placed in bulk on the table. By means of the reciprocating motion of the table by the crank arrangement, the seed cotton comes into contact with knife roller (formed of a number of knife discs).