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The Different Types of Looms are : 

Hand Loom

What is Hand Loom | Hand Loom Weaving

The earliest looms were vertical shaft, with the heddles fixed in place in the shaft. The warp threads pass alternately

through a heddle and through a space between the heddles, so that raising the shaft will raise half the threads (those

passing through the heddles), and lowering the shaft will lower the same threads the threads passing through the

spaces between the heddles remain in place.

Types of Looms - Dobby Loom

A Dobby Loom is a type of floor loom that controls the warp threads using a device called a dobby. Dobby is short for

"draw boy" which refers to the weaver's helpers who used to control the warp thread by pulling on draw threads.

A dobby loom is an alternative to a treadle loom. Each of them is a floor loom in which every warp thread on the loom

is attached to a single shaft using a device called a heddle. A shaft is sometimes known as a harness, but this

terminology is becoming obsolete among active weavers. Each shaft controls a set of threads. Raising or lowering

several shafts at the same time gives a huge variety of possible sheds through which the shuttle containing the weft

thread can be thrown.

A manual dobby uses a chain of bars or lags each of which has pegs inserted to select the shafts to be moved. A

computer assisted dobby loom uses a set of solenoids or other electronic devices to select the shafts. Activation of

these solenoids is under the control of computer program. In either case the selected shafts are raised or lowered by

either leg power on a dobby pedal or electric or other power sources.

On a treadle loom, each foot-operated treadle is connected by a linkage called a tie-up to one or more shafts. More

than one treadle can operate a single shaft. The tie-up consists of cords or similar mechanical linkages tying the

treadles to the lams that actual lift or lower the shaft.

On treadle operated looms, the number of sheds is limited by the number of treadles available. An eight shaft loom

can create 254 different sheds. There are actually 256 possibilities which is 2 to the eight power, but having all

threads up or all threads down isn't very useful. However, most eight shaft floor looms have only ten to twelve

treadles due to space limitations. This limits the weaver to ten to twelve distinct sheds. It is possible to use both feet

to get more sheds., but that is rarely done in practice. It is even possible to change tie-ups in the middle of weaving a

cloth but this is a tedious and error prone process so this too is rarely done.

With a dobby loom, all 254 possibilities are available at any time. This vastly increases the number of cloth designs

available to the weaver. The advantage of a dobby loom becomes even more pronounced on looms with 12 shafts

(4094 possible sheds), 16 shafts (65,534 possible sheds), or more. It reaches its peak on a Jacquard loom in which

each thread is individually controlled.

Another advantage to a dobby loom is the ability to handle much longer sequences in the pattern. A weaver working

on a treadled loom must remember the entire sequence of treadlings that make up the pattern, and must keep track

of where they are in the sequence at all times. Getting lost or making a mistake can ruin the cloth being woven. On a

manual dobby the sequence that makes up the pattern is represented by the chain of dobby bars. The length of the

sequence is limited by the length of the dobby chain. This can easily be several hundred dobby bars, although an

average dobby chain will have approximately fifty bars.

Computer Dobby | Electronic Dobby

A computer dobby loom (Computer-Dobby) takes this one step further by replacing the mechanical dobby chain with

computer controlled shaft selection. In addition to being able to handle sequences that are virtually unlimited, the

construction of the shaft sequences is done on the computer screen rather than by building a mechanical dobby

chain. This allows the weaver to load and switch weave drafts in seconds without even getting up from the loom. In

addition, the design process performed on the computer provides the weaver with a more intuitive way to design

fabricas seeing it on the computer screen is easier than trying to visualize it by looking at the dobby chain.

Dobby looms expand a weavers capabilities and remove some of the tedious work involved in designing and

producing fabric. Many newer cloth design techniques such as network drafting can only reach their full potential on a

dobby loom.

Types of Looms - Jacquard Loom

What is Jacquard Loom | What is Jacquard

The Jacquard Loom is a mechanical loom, invented by Joseph Marie Jacquard in 1801, that simplifies the process of

manufacturing textiles with complex patterns such as brocade, damask, and matelasse. The loom is controlled by

punchcards with punched holes, each row of which corresponds to one row of the design. Multiple rows of holes are

punched on each card and the many cards that compose the design of the textile are strung together in order. It is

based on earlier inventions by the Frenchmen Basile Bouchon (1725), Jean Falcon (1728) and Jacques Vaucanson

(1740)

Jacquard Loom Cards

Each hole in the card corresponds to a "Bolus" hook, which can either be up or down. The hook raises or lowers the

harness, which carries and guides the warp thread so that the weft will either lie above or below it. The sequence of

raised and lowered threads is what creates the pattern. Each hook can be connected via the harness to a number of

threads, allowing more than one repeat of a pattern. A loom with a 400 hook head might have four threads connected

to each hook, resulting in a fabric that is 1600 warp ends wide with four repeats of the weave going across.

The term "Jacquard loom" is a misnomer. It is the "Jacquard head" that adapts to a great many dobby looms such as

the "Dornier" brand that allow the weaving machine to then create the intricate patterns often seen in Jacquard

weaving.

Jacquard looms, whilst relatively common in the textile industry, are not as ubiquitous as dobby looms which are

usually faster and much cheaper to operate. However unlike jacquard looms they are not capable of producing so

many different weaves from one warp. Modern jacquard looms are controlled by computers in place of the original

punched cards, and can have thousands of hooks.

The threading of a Jacquard loom is so labor intensive that many looms are threaded only once. Subsequent warps

are then tied in to the existing warp with the help of a knotting robot which ties each new thread on individually. Even

for a small loom with only a few thousand warp ends the process of re-threading can take days.

Jacquard Computing

The Jacquard loom was the first machine to use punch cards to control a sequence of operations. Although it did no

computation based on them, it is considered an important step in the history of computing hardware. The ability to

change the pattern of the loom's weave by simply changing cards was an important conceptual precursor to the

development of computer programming. Specifically, Charles Babbage planned to use cards to store programs in his

Analytical engine.

Jacquard Weaving

Jacquard weaving makes possible in almost any loom the programmed raising of each warp thread independently of

the others. This brings much greater versatility to the weaving process, and offers the highest level of warp yarn

control. This mechanism is probably one of the most important weaving inventions as Jacquard shedding made

possible the automatic production of unlimited varieties of pattern weaving.

In former times, the heddles with warp ends to be pulled up were manually selected by a second operator, apart from

the weaver. This was known as a drawloom. It was slow and labour intensive, with practical limitations on the

complexity of the pattern.

The Jacquard process and the necessary loom attachment are named after their inventor, Joseph Marie Jacquard

(1752 - 1834). He recognized that although weaving was intricate, it was repetitive, and saw that a mechanism could

be developed for the production of sophisticated patterns just as it had been done for the production of simple

patterns. (Similar ideas were pursued by others before 1750, but Jacquard perfected and popularized the concept by

about 1803.)

Jacquard's invention had a deep influence on Charles Babbage. In that respect, he is viewed by some authors as a

precursor of modern computing science

Mechanical Jacquard Looms

Originally the Jacquard machines were mechanical, and the fabric design was punched in pattern cards which were

joined together to form a continuous chain. The Jacquards often were small and only independently controlled a

relatively few warp ends. This required a number of repeats across the loom width. Larger capacity machines, or the

use of multiple machines, allowed greater control, with fewer repeats, and hence larger designs to be woven across

the loom width.

A factory must choose looms and shedding mechanisms to suit its commercial requirements. As a rule the more warp

control required the greater the expense. So it would not be economical to purchase Jacquard machines if one could

make do with a dobby mechanism. As well as the capital expense, the Jacquard machines are also more costly to

maintain, as they are complex and require higher skilled personnel; also an expensive design system will be required

to prepare the designs for the loom, and possibly also a card-cutting machine. Weaving will be more costly as

Jacquard mechanisms are more liable to produce faults than dobby or cam shedding. The looms will not run as fast,

and down time will increase as it takes time to change the continuous chain of cards when a design changes.

Therefore with mechanical Jacquards it is best to weave larger batch sizes.

Electronic Jacquard

Looms Bonas Machine Company Ltd. launched the first electronic Jacquard at ITMA, Milan in 1983 . Although the

machines were initially small, modern technology has allowed Jacquard machine capacity to increase significantly,

and single end warp control can extend to more than 10,000 warp ends. This avoids the need for repeats and

symmetrical designs and allows almost infinite versatility. The computer-controlled machines significantly reduce the

down time associated with changing punched paper designs, thus allowing smaller batch sizes. However, electronic

Jacquards are costly and may not be required in a factory weaving large batch sizes, and smaller designs. The larger

machines allowing single end warp control are very expensive, and can only be justified where great versatility is

required, or very specialized design requirements need to be met. For example, they are an ideal tool to increase the

ability and stretch the versatility of the niche linen Jacquard weavers who remain active in Europe and the West,

while most of the large batch commodity weaving has moved to low cost areas.

Linen products associated with Jacquard weaving are linen damask napery, Jacquard apparel fabrics and damask

bed linen.

Jacquard weaving of course uses all sorts of fibers and blends of fibers, and it is used in the production of fabrics for

many end uses. Research is under way to develop layered and shaped items as reinforcing components for

structures made from composite materials.

The term "Jacquard" is not specific or limited to any particular loom, but rather refers to the added control mechanism

that automates the patterning.

Types of Looms - Lancashire Loom

The Lancashire Loom was a semi automatic power loom invented by James Bullough and William Kenworthy in

1842. Although it is self-acting, it has to be stopped to recharge empty shuttles.It was the mainstay of the Lancashire

cotton industry for a century.

The principal advantage of the Lancashire loom was that it was semi automatic, when a warp thread broke the

weaver was notified. When the shuttle ran out of thread, the machine stopped. An operative thus could work 4 or

more looms whereas previously they could only a single loom. Indeed the term A Four Loom Weaver was used to

describe the operatives. Labour cost was quartered. In some mills an operative would operate 6 or even 8 looms. .

Though this was governed by the thread being used. By 1900, the loom was challenged by the Northrop Loom which

was fully automatic and could be worked in larger numbers. The Northrop was suitable for coarse thread but for fine

cotton, the Lancashire loom was still prefered. By 1914, Northop looms made up 40% of looms in American mills but

in the United Kingdom, labour costs were not as significant and they only supplied 2% of the British market.

Types of Looms - Northrop Loom

Northrop had worked as a mechanic and foreman, he invented spooler guide while employed by Draper. He

unsuccessfully tried to be a chicken farmer. And it was there he worked on his shuttle-charger for Mr Otis Draper,who

saw a model of the device on March 5, 1889. Draper was also developing the Rhoades shuttle-charger. Northrop was

given a loom to test his idea.

By May 20 he had concluded that his first idea was not practical, and had thought of another idea, On July 5, the

completed loom was running, and as it seemed to have more advantages than the Rhoades loom. The Northrop

device was given a mill trial in October 1889 at the Seaconnett Mills in Fall River. More looms were constructed.

Meanwhile he invented a self-threading shuttle and shuttle spring jaws to hold a bobbin by means of rings on the butt.

This paved the way to his filling-changing battery of 1891, the basic feature of the Northrop loom. Other members of

the Draper organization had developed a workable warp stop motion which was also included. The first Northrop

looms were marketed in 1894.

Northrop Automatic Loom

The principal advantage of the Northrop loom was that it was fully automatic; when a warp thread broke the loom

stopped until it was fixed. When the shuttle ran out of thread, Northrop's mechanism, ejected the depleted pirn, and

loaded a new full one without stopping. An operative thus could work 16 or more looms whereas previously they

could only operate 8. Thus the labour cost was halved. Mill owners had to decide whether the labour saving was

worth the capital investment in a new loom. By 1900, Draper had sold over 60,000 Northrop looms, They were

shipping 1500 a month, were employing 2500 men and enlarging their works to increase that output. In all 700,000

looms were sold.

By 1914, Northop looms made up 40% of American looms. However in the United Kingdom, labour costs were not as

significant and they only supplied 2% of the British market. Northrops were especially suitable for coarse cottons, but

it was said not particular suitable for fines, thus the financial advantage in their introduction into Lancashire was not

as great as it had been in the States. Henry Philip Greg imported some of the first Northrops into Britain in 1902, for

his Albert Mill in Reddish, and encouraged his brother Robert Alexander Greg to introduce Northrops into Quarry

Bank Mill in 1909. The output increased from 2.31 lbs/manhour in 1900, to 2.94 lbs/manhour in 1914. Labour costs

decreased from 0.9d per pound to 0.3d per lb.

Types of Looms - Projectile Loom (Gripper Shuttle Loom)

The multi gripper projectile weaving machine,introduced by sulzer brothers in 1953,was the first system to begin

shuttle weaving.The company and its successors have remained the sole suppliers of projectile weaving machinery.

Pick lengths of weft yarn are drawn from large cones by a weft accumulator.The free end is held in the jaws of a weft

carrier gripper(projectile),88mm long weighing 40kg and the accumulated yarn is threaded to a sophisticated

tensioning and braking system.The Projectile is lifted to the picking position and is propelled across the warp shed by

a torsion bar system.At the other side of the loom,the projectile is recieved,the yarn is released and the projectile is

ejected for eventual return to the picking side.The weft is cut at the picking side and is held at both sides by a

selvedge grippers during beat up and shed change.During the next machine cycle,tucking needles draw the outer

ends of weft yarn into fabric to form selvedges.Usually 10-12 projectiles are associated with a single-width loom.

picking rates are typically 380-420ppm for worsted yarns and 250-300 ppm for woolen yarns.

It offers the following advantages

Low power consuption

Reduced waste of filling material due to unique clean ,tucked-in selvedges

Quick warp and style change

Mechanical and operatonal reliability and ease of use

Low spare parts requirement and easy maintaince

Long machine life

Types of Looms - Rapier Loom

Rapier Weaving is offered by many loom manufacturers and consequently is in widespread use in the worsted and

woolen industry.

In this type of weaving a flexible or rigid solid element called rapier, is used to insert the filling yarn and carries it

through thr shed .after reaching the destination, the rapier head returns empty to pick up the next filling yarn,which

completes a cycle.a rapier performs a reciprocating motion.

Single Rapier Machines

A single,rigid rapier is used in these machines.the rigid rapier is a metal or composite bar usually with a circular cross

section.the rapier enters the shed from one side and pases it across the weaving machine while retracting .therefore

a single rapier carries the yarn in one way only and half of the rapier movement is wasted.also there is no yarn

transfer since there is only one rapier.the single rapiers length is equal to the width of the weaving machine; this

requires relatively high mass and rigidity of the rapier head.for these reasons,single rapier machines are not

popular.however since there is no yarn transfer to rapier tp rapier,they are suitable for filling yarns that are difficult

control.

Double Rapier Machines

Two rapiers are used in these machines.one rapier ,called the giver takes the filling yarn from the accumulator on one

side of the weaving machine, brings it to the center of the machine and transfers it to the decond rapier which is

called taker.the taker retracts and brings the filling yarn to the other side.similar to the single rapier machines,only half

of the rapier movements is used for filling insertion.

Rapier machines are known for their reliability and performance.since 1972,the rapier weaving machine has evolved

into successfull ,versatile and flexible weaving machine.

A very wide range of fabrics with 20 g/m2 to heavy fabrics with around 850 gm2 rapier machines are widely used for

household textiles and industrial fabrics.Designed for universal use,the rapier weaving machine can weave not only

the classic wool,cotton and manmade fibers,but also the most technicaly demanding filament yarns,finest silk and

fancy yarns.

Types of Looms - Air Jet Loom

Air jet loom, as one of the shuttleless looms, transports a yarn into warps using viscosity and kinetic energy of an air

jet. Performance of this picking system depends on the ability of instantaneous inhalation/exhaust, configuration of

nozzle, operation characteristics of a check valve, etc.

Air-jet weaving is an advanced weaving method with high efficiency and productivity

In air-jet looms, the weft is introduced into the shed opening by air flow.

The energy resulting from air pressure is converted into kinetic energy in the nozzle.

The air leaving from the nozzle transfers its pulse to stationary air and slows down.

To this end, in order to achieve a larger rib width, a confuser is developed, which maintains air velocity in the

shooting line.

The confuser drop wires are profiles narrowing in the direction of shoot, and they are of nearly circular cross

section open at the top.

These drop wires are fitted one behind the other as densely as possible. Therefore, they prevent in the

shooting line the dispersion of air jet generated by the nozzle.

Types of Looms - Water Jet Loom

A water jet is more coherant than an air jet.it does not break up easily, and the propulsive zone is elongated,making it

much more effective.it is effective in terms of energy requirements ,it is quite and when the jet does break up, it goes

into droplets which create very little turbulence to disturb the filling.

The droplets spread in such a way as to wet much of the warp; thus a sized warp containing a water soluble adhesive

can be adversely affected.because of this ,water jet weaving is usually restricted to filament yarn,but there is some

hope that it might become economically feasible to weave staple yarns on these looms.

Two main reasons for the efficiency of the water-jet loom are that there are no varying lateral forces to cause the

filling to contract and the moving element is more massive because it is wet.thus there is less chance of fault due to

contact with the warp.

The range of jet, and thus the width of the loom ,depends on the water pressure and the diameter odf the jet.water is

virtually incompressible and a simple jerk pump can be used to give adequate pressure with difficulty.

A firmans hose has a tremendous range but the jet is several cm in diameter;large volumes of water and

considerable pumping powers have to be used .in weaving , a much more modest jet is used; in fact , it is possible to

reduce the diameter of the jet to some 0.1 cm, and the amount of water used per pick is commonly less than 2c.c.

even with these small jets , it is possible to weave at upto 2 meters in width with small power consuptions.it is also

possible to weave at upto 1000 picks/min on narrower looms .several forms of water-jet loom have now become

established.

Type of Looms - Circular Loom

The circular weaving machine proposed by the invention is designed for the manufacture of tubular fabrics and has

an annular frame with an upper ring plate and a lower ring plate Vertically moving laces are fitted to direct the warp

ends and are mounted at constant intervals round at least one circular trackway . The two ring plates have bores in

them for mounting and directing the laces . The lower ends of the laces have follower rollers which operate in

conjunction with a cam plate.

History of Weaving

The weaving is a process of formation of fabric with interlacement of two or more sets of yarns using a stable

machine called loom. Human beings have started using the woven fabrics since the drawn of history. If we exclude

the stone age period, we may conveniently say the history of civilization is also, to some extent, the history of

weaving. Aitken says there is evidence that the Egyptians made woven fabrics over 6000 years ago. Though primitive

civilizations used coarser threads to make fabrics which were crude and coarse, there are references of fine fabrics

made from filament of silk in China. Silk was one of the most important product in China 4000 years ago. In India too,

there existed some of the finest hand woven fabrics.

Warp Yarn

In weaving, the warp is the set of lengthwise yarns through which the weft is woven. Each individual warp thread in a

fabric is called a warp end. Warp means "that which is thrown across" . When weaving with a loom, the warp yarns

are fully attached before weaving begins. Warp is spun fibre. The spin of the fiber can be in either an "s" twist or a "z"

twist. These twist directions make yarn that is similar to hands; each the reverse of the other. . These fibres provided

a strong enough thread to be held under tension as the warp. With the improvements in spinning technology during

the Industrial Revolution, it became possible to make cotton yarn of sufficient strength to be used as the warp. Later,

artificial or man-made fibres such as nylon or rayon were employed. The weft is the yarn that is woven back and forth

through the warp to make cloth.

Weft Yarn 

In weaving, weft or woof is the yarn which is drawn under and over parallel warp yarns to create a fabric.. The weft is

a thread or yarn of spun fibre. The original fibre was wool, flax or cotton. Nowadays, many synthetic fibers are used in

weaving. Because the weft does not have to be stretched in the way that the warp is, it can generally be less

strong.The weft is threaded through the warp using a shuttle. Hand looms were the original weaver's tool, with the

shuttle being threaded through alternately raised warps by hand. Inventions during the 18th century spurred the

Industrial Revolution, and the hand loom became the more robust spinning frame with the flying shuttle speeding up

production of cloth, and then the water frame using water power to automate the weaving process. The power loom

followed in the 19th century, when steam power was harnessed.

Handloom industry

It is still not certain when the weaving process was introduced to human society. It is clear from many historical

records that weaving originated long before the time of Jesus Christ. Except few activities else where, the major

developments in textile took place in England. In England the major shift from agriculture to woolen industry came in

the 14th century. During all these years and a few hundred years after 14th century, the cloth was produced on hand-

looms which were not equipped with fly shuttle. Prior to Industrial Revolution, woven fabrics was produced by atleast

two people employed on loom.

In 1733, John Kay invented the fly shuttle which enabled weft to be inserted more rapidly. John Kay, a weaver, further

incorporated a mechanism with which, a weaver could sit at the centre of the loom and merely pull the handle to

make the shuttle move from one end of the fabric to insert a weft thread.

As a result of increased weaving speed, the hand spinning method of yarn production could not meet the requirement

of fly shuttle looms and subsequently the mechanical spinning also developed rapidly in Britain with Hargreave's

spinning Jenny (1770), Ark Writh's spinning machine (1769) and cromption spinning mule (1779). The development

of the mechanical spinning system induced further developments in the loom. Edmund Cart Wright, an English clergy

man, invented a so called powerloom which could be operated from a single point by two strong man.

Powerlooms

Earlier version of powerloom were run by two man. Fortunately steam power was available by 1765. Soon

powerlooms were driven by steam and most of the wooden parts were replaced with iron. After the steam engine and

cast iron in early 1800, great attention was paid to increasing productivity of the machine. To help achieve the

increase in productivity, William Radeliffe patented a dressing frame in 1803 for sizing and drying the warp threads

prior to winding on to a weavers beam. Fast development in the loom took place and by 1821 there were over 50,000

looms in operation in some 32 mills in the north of England. In just over 10 years from that date, the number had

increased to some 1,00,000 and the basic loom had almost developed to the machine we know today. Also between

1819 and 1842 the average speed of the powerloom had increased from 60 to 140 picks per minute with the rise on

productivity, as a result England became world's richest industrial power.

Automatic Looms

Traditional looms then were stopped every few minutes in order to replace the empty weft pirns or cop in the shuttle

and this limited the number of looms, a weaver could operate to about four. James Northrop, an English man who

emigrated to America and worked for the Draper Corporation, completed an automatic weft transfer system which

replaced the weft pirn in the shuttle without slowing or stopping the loom in 1889. This mechanism enabled the

weaver to tend 16 looms. The Northrop Automatic looms quickly came to use in America, so that by 1930, 90% of the

American looms were automatic compared with only 5% in Britain. Similar developments took place elsewhere also,

Ruti, a major loom maker of Switzerland manufactured automatic bobbin changing Northrop loom in 1898. In Japan

also, Toyoda, Sakamoto, Tsudakoma, etc also developed shuttle looms with automatic weft transfer. After World War

II, more productivity and efficiency were essential to overcome increasing labour costs in Western countries. It was

also realised that more productivity is the key to reducing manufacturing costs of the loom. All attempts were

concentrated to studying various factors affecting speed of the loom and the loom with higher speed were made

available.

Limitations of Shuttle Looms

Despite the relatively high speed and efficiencies in loom with conventional picking, productivity of these machines

will continue to be limited as long as their fundamental constructions involved the use of a shuttle propulsion. Vincent

has shown that the power required for picking is proportional to the cube of the loom speed. If the loom speed is

increased from 200 to 300 picks per minute, the power requirement would increase by a factor of (3/2)3 i.e. 3.4 times

approximately. This results in following disadvantages 

Greater strain imposed on the picking mechanism, thus rendering it liable to frequent failure.

Greater amount of noise and vibration.

Because of superior energy in shuttle, greater strain is again imposed on the checking mechanism.

The movement of shuttle will be more difficult to control and there will be a greater possibility of its ejection

from the loom.

The dynamic problems created by the picking and checking mechanism and the inherent process of pirn winding for

shuttle looms had encouraged the loom makers to develop alternative means of weft insertion in which heavy shuttle

is not projected forwards and backwards across the width of the loom. It is customary to refer these looms as

shuttleless looms. The various shuttleless loom that have been developed over a period of about 50 years can be

classified into various groups.

Projectile Looms

Rapier Looms

Fluid Jet Looms

Multiphase Looms

Parts of a Loom | Loom Components | Looms and Weaving | Looming The Major Loom Components are the warp beam, heddles, harnesses, shuttle, reed and takeup roll. In the

loom, yarn processing includes shedding, picking, battening and taking-up operations

Weaving Shedding | Shedding | What is Shedding

Shedding is the raising of the warp yarns to form a shed through which the filling yarn, carried by the shuttle,

can be inserted. The shed is the vertical space between the raised and unraised warp yarns. On the modern

loom, simple and intricate shedding operations are performed automatically by the heddle or heald frame,

also known as a harness. This is a rectangular frame to which a series of wires, called heddles or healds,

are attached. The yarns are passed through the eye holes of the heddles, which hang vertically from the

shedding harnesses. The weave pattern determines which harness controls which warp yarns, and the

number of shedding harnesses used depends on the complexity of the weave. Two common methods of

controlling the heddles are dobbies and a Jacquard Head.

Picking

As the shedding harnesses raise the heddles or healds, which raise the warp yarns, the shed is created.

The filling yarn in inserted through the shed by a small carrier device called a shuttle. The shuttle is normally

pointed at each end to allow passage through the shed. In a traditional shuttle loom, the filling yarn is wound

onto a quill, which in turn is mounted in the shuttle. The filling yarn emerges through a hole in the shuttle as

it moves across the loom. A single crossing of the shuttle from one side of the loom to the other is known as

a pick. As the shuttle moves back and forth across the shed, it weaves an edge, or selvage, on each side of

the fabric to prevent the fabric from raveling.

Battening

As the shuttle moves across the loom laying down the fill yarn, it also passes through openings in another frame

called a reed (which resembles a comb). With each picking operation, the reed presses or battens each filling yarn

against the portion of the fabric that has already been formed. The point where the fabric is formed is called the fell.

Conventional shuttle looms can operate at speeds of about 150 to 160 picks per minute.

With each weaving operation, the newly constructed fabric must be wound on a cloth beam. This process is called

taking up. At the same time, the warp yarns must be let off or released from the warp beams. To become fully

automatic, a loom needs a filling stop motion which will brake the loom, if the weft thread breaks

For all this to happen, the yarn has to be prepared. The weft, or filling must be wound tightly on the correct size pirns,

quills or bobbins. Weaving happens at great speed so the yarn must be at the correct tension when it leaves the

shuttle. The warp passes through the heddles which stretch it at each pick, and through the reeds which are abrasive.

The warp is thus sized, that is coated with a mixture that can include china clay and flour, to give it extra strength and

to act as a lubricant. It is dressed or wetted while passing through the loom. The warp, hundreds of ends of yarn

rolled in parallel, comes on a wooden beam. Before weaving can commence each end must be passed through the

heddles and and reeds, a process known as looming.

Chilkat weaving

Chilkat weaving is a traditional form of weaving practiced by Tlingit, Haida, Tsimshian, and other Northwest coastal

tribes of Alaska and British Columbia. Chilkat blankets are worn by high-ranking tribal members on civic or

ceremonial occasions, including dances.

Background of Chilkat Weaving 

The name derives from the Chilkat tribe in Klukwan, Alaska on the Chilkat River. The Tsimshian might have invented

the technique. Chilkat weaving can be applied to blankets, robes, dance tunics, aprons, leggings, shirts, vests, bags,

hats, and wall-hangings. Chilkat clothing features long wool fringe that sways when the wearer dances. Traditionally

chiefs would wear Chilkat blankets during potlatch ceremonies.

Chilkat weaving is one of the most complex weaving techniques in the world. It is unique in that the artist can create

curvilinear and circular forms within the weave itself. A Chilkat blanket can take a year to weave. Traditionally

mountain goat wool, dog fur, and yellow cedar bark are used in Chilkat weaving. Today sheep wool might be used.

The designs used Northwest Coast formlines, a traditional aesthetic language made up of ovoid, U-form, and S-form

elements to created highly stylized, but representational, clan crests and figures from oral history - often animals and

especially their facial features. Yellow and black are dominant colors in the weavings, as is the natural buff color of

the undyed wool. Blue can be an secondary color.

Looms used in Chilkat weaving only have a top frame and vertical supports, with no bottom frame, so the warp

threads hang freely. The weaver works in vertical sections, as opposed to moving horizontally from end to end.

Finger Weaving | How to Finger Weave

Fingerweaving is a Native American art form used mostly to create belts, sashes, straps, and other similar items

through a non-loom weaving process. Unlike loom-based weaving, there is no separation between weft and warp

strands, with all strands playing both roles

Finger Weaving History

North and Central American Finger weaving

Some patterns and color combinations were originally restricted to certain societies or clans, while others were

available for general use by all. Belts, sashes, leg bands, capes, gun straps, even dresses, shirts, and pants were

created by the sometimes intricate patterns and methods. Often beads or feathers were interwoven into the patterns

of the articles.

The French Voyagers (fur traders in the northern US and southern Canada) adapted the finger weaving patterns to

create belts and sashes which showed which company they belonged to. The belts were the original weight belts, as

they added extra support to their stomachs when they were lifting heavy canoes or packets of beaver pelts, which

sometimes weighed up to 600 lbs. The Spanish conquistadors used fingerwoven sashes to proclaim which command

they were in, as well as to record their conquests over the Native Americans.

South American Finger weaving

Although South American styles shared much in common with those from North America, some differences are

reliably observable. In addition to many of the specific weaves from the north, additional atyles were created by using

multiple weft strands at a time.

Basic Weaves

The most basic weave is called a diagonal weave, as it creates a series of parallel lines running down the length of

the weave at a diagonal. Whether one weaves from left to right or from right to left does not matter, as the pattern is

the same, however, the direction must stay the same or the pattern will change.

As with loom weaving, one starts with an even number of warp strands, but with no weft strand. Divide the warp

strands into two groups, a top and bottom row. Take the top left (or top right) strand, and run it between the top and

bottom rows, turning it into a weft. Reverse the position of each warp strand (from top to bottom or bottom to top),

making sure to keep all strands in the same order and placement to form a single interlocked row.

For the second row, take the new top left (or top right) warp strand, and tuck it between the top and bottom, forming a

new weft strand. Again, interlink the top and bottom rows, making sure to use the old weft strand from row #1.

Continue this process until the desired length is completed.

Other common, but more difficult patterns include those of lightning bolts, arrowheads, and chevrons. By making

slight changes to the weaving process, a wide variety of unique patterns can be created.

Inkle weaving

Inkle weaving is a type of warp-faced weaving where the shed is created by manually raising or lowering the warp

yarns, some of which are held in place by fixed heddles on a loom known as an inkle loom. Though inkle weaving

was brought to the United States of America (US) in the 1930s, the inkle itself seems to predate this by several

centuries, being referred to in Shakespeare's Love's Labour's Lost.

Inkle weaving is commonly used for narrow work such as trims, straps and belts.

Inkle Looms 

Inkle looms are constructed in both floor and table-top models. Either model is characterized by a wooden framework

upon which dowels have been fastened. These dowels will hold the warp threads when the loom has been dressed.

One of the dowels is constructed so that its position can be adjusted. This tensioning device will be taken in as

weaving commences and the warp threads become shorter. Additional equipment includes yarn of the weaver's

choice, yarn or thread for forming heddles and a shuttle to hold the weft. A notebook is also handy for charting

weaving diagrams.

Process of Inkle Weaving

The inkle loom is threaded with warp threads according to the weaver's design, alternating between yarn that that can

be raised and lowered and yarn that is secured in place through the use of the heddles. The raising and lowering of

these warp threads creates the shed through which the weft thread will be carried on a shuttle. The weaver should

make one pass with the shuttle with each opening of a shed through the raising and lowering of threads.

A simple raising and lowering of threads creates a plain-weave band in which warp threads are slightly offset. Weft

threads are only visible at the edges of the band and the weaver may wish to take this into account by warping

threads that will form the edges in the same color as the weft.

As the weaving commences, the warp threads will shorten on the loom and the weaver will need to adjust the tension

periodically. As the inkle band progresses, it will also get closer to the heddles. The weaver will also need to advance

the warp thread along the bottom of the loom to open up new weaving space. In her book "Inkle Weaving," Helene

Bress recommends loosening the tension when you are ready to advance the warp. Once you have done so, tighten

the tension again and resume your weaving.

There are other more advanced techniques in which, instead of merely allowing warp threads to alternate in their up

or down positions, individual threads are brought to the surface to form a brocaded pattern. One side of the band will

show the exposed surfaces of warp threads while, on the other side of the pattern, the weft thread will be visible

An inkle loom is also useful in the practice of tablet weaving for its added portability. Simply thread the warp onto the

loom but use cards instead of alternating between free-hanging and heddle-secured yarn.

Uses of Inkle Weaving

The narrow bands that inkle weaving forms are ideal for using as belts or for decorating the edges of a garment. (This

weaver finds a narrow strip of hand-made fabric to be ideal as a strap for use in yoga. The many varieties of color

and pattern are limited only by the weaver's imagination.

Tablet weaving

Tablet Weaving (often card weaving in the United States) is a weaving technique where tablets, also called 'cards',

are used to create the shed the weft is passed through. The technique is limited to narrow work such as belts, straps,

or garment trim.

The origins of this technique go back at least to the early Iron age. Examples have been found at Hochdorf,

Germany, and Apremont, France. Tablet-woven bands are commonly found in Iron age graves and are presumed to

be standard trim for garments among various peoples, including the Vikings. As the materials and tools are relatively

cheap and easy-to-obtain, tablet weaving is popular with hobbyist

weavers.

Tools

The tablets used in weaving are typically shaped as regular polygons, with holes near each vertex and possibly at the

center, as well. The number of holes in the tablets used is a limiting factor on the complexity of the pattern woven.

The corners of the tablets are typically rounded to prevent catching as they are rotated during weaving.

In the past, weavers made tablets from bark, wood, bone, horn, stone, leather, or a variety of other materials. Modern

cards are frequently made from cardboard. Some weavers even drill holes in a set of playing cards. This is an easy

way to get customized tablets or large numbers of inexpensive tablets. The tablets are usually marked with colors or

stripes so that their facings and orientations can be easily noticed.

Tablet Weaving Loom

The fundamental principle is to turn the tablets to lift selected sets of threads in the warp. The tablets may be turned

in one direction continually as a pack, turned individually to create patterns, or turned some number of times

"forward" and the same number "back". Twisting the tablets in only one direction can create a ribbon that curls in the

direction of the twist, though there are ways to thread the tablets that mitigate this issue.

Traditionally, one end of the warp was tucked into, or wrapped around the weaver's belt, and the other is looped over

a toe, or tied to a pole or furniture. Some traditional weavers weave between two poles, and wrap the weft around the

poles. Commercial "tablet weaving looms" adapt this idea, and are convenient because they make it easy to put the

work down.

Some modern weavers thread each card individually, but this is time consuming. The traditional threading method is

to put all the threads through the holes of an entire deck. Then, starting at the pair of cards farthest from the bobbins,

the threads are pulled from between each pair of cards out to the length of the warp, and hooked or tied on each end.

If the cards remain "paired", so that alternate cards twist in opposite directions, continuous turning does not twist the

ribbon. Some weavers in some patterns flip alternate cards, "unpairing" them. This makes it easier to turn individual

cards.

A shuttle about twice as wide as the ribbon is placed in the shed to beat the previous weft, then carry the next weft

into the shed. Shuttles made for tablet weaving have sharp edges to beat down the weft. The best shuttles have

plates to cover the bobbin, and keep it from catching the warp. Simple flat wooden or plastic shuttles work well for

weaving with large yarns, but weaving with finer threads goes more quickly with a tablet-weaving shuttle.

Patterns are made by placing different-colored yarns in different holes, then turning individual cards until the desired

colors of the weft are on top. After that, a simple pattern, like a stripe, small diamond or check, can be repeated just

by turning the deck of tablets.

Tablet weaving is especially freeing, because any pattern can be created by turning individual tablets. This is in

contrast to normal looms, in which the complexity of the pattern is limited by the number of shafts available to lift

threads, and the threading of the heddles.

Tablet weaving can also be used to weave tubes or double weave. The tablets are made to have four levels in the

warp, and then two sheds are beat and wefted, one in the top pair of warps, and the other in the bottom pair, before

turning the deck. Since groups of tablets can be turned separately, the length, width and joining of the tubes can be

controlled by the weaver

Taniko Weaving | Taniko

Taniko (or taaniko), is a traditional weaving technique of the Māori of New Zealand related to twining. Taniko

Weaving may also refer to the resulting bands of weaving, or to the traditional designs.

The Taniko technique does not require a loom, although one can be used. Traditionally free hanging warps were

suspended between two weaving pegs and the process involved twining downward. The traditional weaving material

is "muka", fibre prepared from the New Zealand flax . The muka fibre was dyed using natural dyes

Tapestry Weaving | Tapestry 

Tapestry is a form of textile art, woven on a vertical loom. It is composed of two sets of interlaced threads, those

running parallel to the length (called the warp) and those parallel to the width (called the weft); the warp threads are

set up under tension on a loom, and the weft thread is passed back and forth across part or all of the warps. Tapestry

weaving is weft-faced weaving, in which all the warp threads are hidden in the completed work, unlike cloth weaving

where both the warp and the weft threads may be visible. In tapestry weaving, weft yarns are typically discontinuous;

the artisan interlaces each colored weft back and forth in its own small pattern area. It is a plain weft-faced weave

having weft threads of different colours worked over portions of the warp to form the design.

Most weavers use a naturally based warp thread such as linen or cotton. The weft threads are usually wool or cotton,

but may include silk, gold, silver, or other alternatives. Both craftsmen and artists have produced tapestries. The

'blueprints' on cardboard (also known as 'tapestry cartoons') were made by artists of repute, while the tapestries

themselves were produced by craftsmen

The emphasis on weaving productivity and weaving quality has developed the weaving technology very much and as

a result the working hours required to weave fabric from loom have been reduced from about 20 to 0.25 during the

last 125 years, and in the last 50 years there has been a reduction of 95% in operative hours per standard unit

produced. Majority of the developments are taking place on the shuttleless looms in the following directions :

To increase productivity of the loom.

To make the looms more flexible for different kinds of fabric.

To reduce the down time for changing style, etc.

Application of electronic control mechanisms to increase automation

Development of accessories such as dobby, jacquards, etc.

In addition to these, the newer looms are simple in design, the motions are more reliable, consumes less energy and

have lower maintenance cost.

Productivity of Looms

The Production rates of the various types of looms are presented for comparison in Table

Loom type Available width in cms Speed in rpm Weft insertion rates(ppm)

Projectile

Sulzer Ruti P7100             190-540                 320                      1100-1200

Sulzer Ruti P7200             190-540                 430                      1500

STB Russia                      180-330                 300                     750

Rigid Rapier

SACM                              150                       550                      1110

Dornier                            150-400                460                      1000

Gunne                             230                       330                      1200

Flexible Rapier

Somet                             165-410                 550                      1300

Vamatex                          160-380                510                      1300

Sulzer Ruti                       110-280                 325                      1200

Nuovo Pignone                 220-420                 440                      1000

Water Jet

Metor SPA                       230                         1000                    1600

Nisson                            150-210                   1000                    2000

Tsudakoma                    150-210                   1000                     2000

Air Jet

Sulzer Ruti                     upto 300                  750                       1600

Picanol Omni                  190-380                  800                       1800

Picanol Delta                  190                         1110                     2000

Toyoda                          150-330                  850                       2000                           

Tsudakoma                   152-340                   1000                     2200

Lakshmi Ruti                  190                         500                       1200

Dornier                          430                         600                       2520

Linear Multiphase

Elitex                            about 190               1100-1600               2000-3000

Drum type Multiphase 

Sulzer M8300                 190                        3230                       6088

Out of these single phase looms, Air jet loom is having maximum speed and maximum weft insertion rate. Because of

the very high quality of yarn required, the yarn must be of very high standard, otherwise the loom stoppages due to

warp breaks and weft breaks will be high. The efficiency achieved will be in the order of 93 to 95%.

Other looms like projectile and repair will give an efficiency of about 90 to 95%. The cover of the fabric in air jet will

not be as good as projectile and rapier looms. Efficiency in multiphase loom is in the order of 90 to 95% These are

the speeds obtained by the weavers at commercial level. The main reason for targeting higher productivity is to

reduce the cost of production, especially labour cost. The increase in speed is being achieved the improvement in all

major functional parts of the modern looms

Today the market particularly demands wide variety as much as possible at the lowest possible cost. These

machines provide the feature such as :

The possibility of weaving more difficult products in terms of yarn employed and also in combinations

Application potential in all weaving sectors.

Sulzer Ruti 6300 rapier loom will weave not only fashion, fabrics with us many as 8 weft colours but also furnishing

fabrics, simple print base fabrics and denims as efficiently as light to heavy weight industrial fabrics.

The terry plus airjet terry weaving machines of Gunne not only permit greater pile height and heavier fabrics, it also

offers greater flexibility in operation with the ability to change the fabric width and pile height. On the machine the

drawing width can be changed using the same reed, simply by shifting the weft stop motion and the weft cutter. The

pile height is programmable within the same fabric. Special fabric constructions with different pile heights on front and

back are also possible. For Sulzer P7300 projectile looms a variety of back rest roller and cloth take up systems are

available to suit the density and the type of fabric woven.

Minimum Down Time of Weaving Machine

Many of the weaving machine manufacturers offer quick style change (QSC) system. The basic idea of these

developments is to prepare module outside the weave room and keep them ready for a switch over with empty

module in the weaving machine. Dornier demonstrated quick style changes from a fine worsted fabric to a pure

cashmere fabrics in less than 30 minutes. Similarly, almost all major weaving machine makers offer their own version

of QSC. Dornier offers Fast Dobby Change (FDC) which allows a mill exchange a dobby shedding for a cam drive

when a basic style is being woven and higher shedding machine speeds are possible. The exchange times is not

more than 1.5 hours per occurrence.

Electronic Control Mechanism in Weaving 

The use of central microprocessor control system and automatic functional with bidirection communication and

diagnostic features are the common features of most of these latest weaving machines. Sulzer Ruti P7100 with

central microprocessor control, electronically controls progressive weft break, automatic weft feed backup which

switches over to a feeder head with intact weft intact weft thread in the event of weft break, at the same time

informing the weaver an optical automatic weft break repair and package handling system.

In repair machines electronic control weft tensioner reduces the yarn tension specially during insertion. The opening

and closing time can be selected according to the material usually at yarn pick up. Automatic package switching

device prevents the machine from being stopped in the event of a weft break between the package and the weft

feeder. The microprocessor switches over immediately to a reduced number of packages in the circle, so that the

machine continues to run.

Electronically controlled warp let off and cloth take up units ensure high degree of fabric regularity and prevent all

kinds of start and stop marks. Electronic monitoring control system have simplified the communication with the

machine and facilitate its easy handling by any one concerned with the operation of the machine e.g. weaver,

technical, maintenance, personnel, etc.

In airjet weaving machine electronic let-off maintains consistent warp tension from full beam to empty beam.

Electronic cloth take up generates a pick density resolution of 0.1 picks/cm and holds it constant, under all operating

conditions.

In terry plus airjet terry weaving machine of Gunne Web Machinen Fabric GMBH & Co. The microprocessor monitors

the entire insertion cycle and keeps all the different elements perfectly synchronized.

Other Developments

(A) Tuck-in-Devices

Some of the important development are new tuck in motions based on pneumatic. The principle of pneumatic trucking

in is the use of air to hold the filling end and then forcing the filling end to be tucked in, in the next shed, by air. In

airjet weaving the automatic weft repairer which repairs the weft break and starts the machine automatically is made

simple by using mechano pneumatic device. It is a positive factor in higher weaver allocation and increased

efficiency. Dornier exhibited their pneumatic tucker on two airjet weaving machines (LTN F8/J and LWV2/E).

Tsudokama demonstrated their ZNT needleless tuck-in on two airjet weaving machine. Somet showed its patented

tucking motion on a clipper airjet machine. Elimination of tuck in needle by pneumatic tuck in motion enables the loom

run much faster as compared to mechanical devices.

(B) Electronic Jacquard Head

Grosse has introduced its patented UniShed positive electronic jacquard head. The shed formation in the UniShed is

achieved by leaf spring. Each leaf spring is connected to a heddle that controls one warp end. The leaf springs which

are controlled by actuators control the bottom shed as well as the top shed (positive shed type). The dimensions of

the jacquard head and the individual control of each heddle (warp end) allow the heddles to be set vertically. These

settings permit the elimination of harness cords, hooks, magnets, pulleys, pull down springs and more significantly,

the gantry. The jacquard head is mounted directly on the side frame of the weaving machine, thus allowing quick

style changes.

(C) Jacquard Shedding Mechanism

Staubli's Unival 100 electronic jacquard shedding mechanism offers a new concept. The shed formation is achieved

by controlling each individual warp end with a stepping motor. The harness cord / warp end selection is performed

electronically and hence fabric design is achieved in the same way as any electronic jacquard system. The design of

the Unival 100 permits the elimination of hook and the gantry.

(D) Weft Package Handling

Complete automatic weft package handling, loading the package frame and package changing can be incorporated

on Sulzer Ruti projectile weaving machines and Tsudakoma Airjet weaving machines. These include automation

equipment for detecting the broken picks with drawing it from the open shed, correcting the cloth fell position and

restarting the machine. The entire cycle is completed in about 12 seconds.

(E) A Loom Developed by SITRA

The modern shuttleless looms not only produce faster, but also the cloth produced by these looms possess much

better quality as compared to conventional looms. The main problem faced by the decentralized weaver is that

imported shuttleless looms are very expensive. In order to overcome this disadvantage to a decentralized sectoer

SITRA has developed a low cost rapier shuttleless loom with a likely price tag of around Rs. 3.5 lakhs. The major

advantages of this loom as compared to ordinary loom are:

The speed of the machine can be increased by 25%.

When the four colour weft is used, the speed increase will be more than 40% compared to drop box loom.

Weaving defects in fabric will be considerably reduced.

Since rapier machine feed weft yarn from cone, the process of pirn winding is eliminated.

10 to 15% increase in efficiency is possible when compared to ordinary power looms.

Higher work assignment is possible.

Because of low cost, power loom units can afford to install this machine

(F) Other Attachments

To achieve minimum defects in fabrics, with increase in loom efficiency and to meet the requirements of export

quality fabric, the following additional motions may be installed in ordinary power looms.

Electronic Weft Feelers

Electro Mechanical Weft Fork

Electronic Warp Stop Motion

Sudden Brake Motion

Positive Let off Motion

These devices will increase the productivity, reduce fabric defects due to double picks, weft cracks, starting marks,

broken picks, uneven pick density, etc.

The advantage derived like minimum defects, increase in production, improved quality and increase in efficiency will

enable the manufacturer to recover the amount invested in a very short period. Moreover the loom allotted to a

weaver can also be increased depending on the variety woven.

So the improve quality, production, efficiency and to face competition when textiles will be available from other

countries also, the manufacturers have to expeditiously modernize and tune up the operational efficiency of their

existing loom.

Modern Weaving - Shuttleless Weaving

Modern weaving machines | Shuttleless Weaving Machines stand out as an expensive class compared to

conventional machines in terms of capital investment. This basic difference requires certain prerequisites to be

considered while planning to venture into modern weaving machines.

The quality of yarn used on shuttleless weaving looms is the prime criteria considered for quality weaving. The

machine parameters to be controlled for an optimised preparatory operation have been dealt with respect to winding,

war ping and sizing operations. Guidelines for machine stoppages corresponding to warp and weft breakages in

weaving are considered as important in deciding the efficiency of a shuttless weaving shed.

Introduction to Shuttleless Weaving

For the successful installation of shuttleless looms, it becomes inevitable to go for quality yarn and optimization of the

preparatory operations prior to weaving. A better quality yarn leads to a quality warp and sized beam which

consequentially gives and efficient weaving operation both qualitatively and quantitatively. The parameters to be

checked as regards yarn quality, winding of warp and weft yarns, warping and sizing are dealt with in some detail in

the following sections.

Yarn Quality Requirements for Shuttleless Weaving 

Tension on the warp on a high speed shuttleless weaving machine is higher than that on conventional loom. On

some Repier looms, interference by rapiers, at the initial points of entry and terminal point of shed exit, can cause

bending of the top yarn sheet around the rapier head producing excessive warp strain on the selvedge region of war

p. Weft tension on Sulzer Ruti projectile weaving machine, is equally high, where tucked-in selvedge is for med.

Consistency of single end strength, C.V. of count and elongation is essential. Quality of yarn should be at least within

25% Uster which means the quality is among the best 25% of the mills in the world. Normally shuttleless weaving

machine works three to four times faster and if the quality of war p remains the same, warp breaks will increase three

to four times resulting in low production. Yarn should be more even and the following parameters of yarn are to be

critically reviewed; C. V. of count, single thread strength, C. V. of single thread strength, imperfections per 1,000

meters such as thick places, thin places, and neps. Hairy yarn will not be suitable in air jet weaving as it will misdirect

the weft insertion.

Warp and Weft Preparation for shuttleless weaving 

It is absolutely necessary that machine stoppage rate per 10,000 war p ends and 1,00,000 picks should be

considerably reduced for successful installation of shuttleless looms. Because of much smaller shed size,reed sweep

and abrasion time, the war preparation standards acceptable for automatic looms will lead to less warp breakages if

the same yarn is used on high speed looms. Yarn imperfections which would pass into the cloth on an automatic

loom fail to do so on a machine like projectile loom because of the following reasons:

The reed is less flexible.

The characteristics of beat-up are considered to be more detrimental than those with conventional sley.

When the movement of adjacent shed is impeded due to some projection hanging in the form of wild yarn,

fluff, scissoring action of the knots, etc, hindrance in the path of the yar n will be chopped off to cause a

multiple break.

Number of abrasion cycles is more because of high speed.

Winding

All medium and fine counts and all blended yarns with polyester components should be wound on automatic winding

machines like Autoconer, Murata, etc. In choosing optimum clearing settings, indiscrimate removal of thick places is

not desirable since removal of each fault is replaced by another fault namely a knot. Knots act as sharp instruments

on the adjacent threads, besides being responsible for peak tensions generated during weaving. Tail ends of knots

come in the way of clear shed formation and can be a cause of multiple breaks. Hence, each thick place is to be

assessed with respect to its length, and only objectionable faults may be removed. This is possible only with

electronic yarn clearer in conjuction with Uster Classimat which classifies yar n faults into twenty one categories

(reference length & C.S.) The size of the tail ends of knots should be small. The knotter is to be selected based upon

the yarn number. A spliced yarn gives good results. It would be desirable that a splicer is provided instead of a

knotter on the winding machine to give good results and to get rid of all the disadvantages of knots. A large no. of

automatic winding machines are equipped with knot / splice tester which ensures 90-95% prefect joints.

Warping

At warping, the goal should be to avoid missing ends. Number of thread breakages should not exceed seven per 10

million meters. This can be achieved by ensuring a top quality yarn package and by following the warping process

parameters mentioned below :

Precise creel alignment

Reliable stop motion on creel and on warping drum, so that broken ends are traceable for knotting.

Minimum wobbling of warping beams.

Uniform selvedge with good flanges.

Yarns should by preferably warped on spindle driven machines to avoid thermal damage due to abrasion.

Warping machines such as Benninger or Hacoba are preferable. With drum driven warpers such as the BC

Warper, the following precautionary measures are to be taken : 

A) Frictional drum should be kept in a polished state.

B) Brake should be very efficient.

C) Aluminium cast flanges should be used to get faulteless selvedges.

D) Breakages rate should not exceed 0.3~0.5 breaks per 1000 m / 500 ends.

E) For wider width looms, wider war ping machines are preferred.

Sizing

The process of sizing greatly influences the performance of the shuttleless weaving machine. The concept of single

end sizing is more ideal for yarn prepared for all shuttleless weaving machines particularly wider width machines with

a large number of ends. Single end sizing facilitates proper encapsulation of size on the yarn and reduces hairiness

particularly of blended yarns resulting in a ver y clear shed formation which is a must for shuttleless weaving. Double

size beams are recommended to avoid over crowding. An optimum number of ends in the size box is given by

optimum ends = 0.5 x (width of nip of size box) / dia. of yarn.

Weft Preparation

Weft insertion rate is high and unwinding is intermittent on shuttleless weaving machines. Hence it is necessary to

have a hard wound package. It is essential to have anti patterning device to prevent slough-off on the fabrics. For

spun yar ns, parallel wound package with core diameter of package of 95 mm and a traverse of 90 mm give a good

performance. Smaller core diameter of package increases the unwinding tension and enhances the possibility of high

weft breakage. Weft accumulators are to be used on high speed weaving machines when the weft insertion rate is

above 1000 m/min.

The parameters and machinery in preparatory for the conventional shuttle looms should be thoroughly assessed and

suitably modified or replaced for their performance for the efficient functioning of a shuttleless weaving shed. The

above factors play a deciding role in giving quality weaving and better returns thereof.

Loom

What is Loom | What is a Loom | Define Loom | Loom Definition | Definition of Loom

Loom is a machine or device for weaving thread or yarn into textiles. Looms can range from very small hand-held

frames, to large free-standing hand looms, to huge automatic mechanical devices. The ancient Egyptians and

Chinese used looms as early as 4000 BC. In practice, the basic purpose of any loom is to hold the warp threads

under tension to facilitate the interweaving of the weft threads. The precise shape of the loom and its mechanics may

vary, but the basic function is the same.

Types of Looms | Types of Weaving Looms

Hand Looms | Hand Loom Weaving

What is Hand Loom

The first and original hand loom was vertically twist-weighted types, where threads are hung from a wooden piece or

branch or affixed to the floor or ground. The weft threads are manually shoved into position or pushed through a rod

that also becomes the shuttle. Raising and lowering each warp thread one by one is needed in the beginning. It is

done by inserting a piece of rod to create a shack, the gap between warp threads in order for the woof to easily

traverse the whole warp right away.

Ground Looms

Horizontal ground looms permit the warp threads to be chained between a couple of rows of dowels. The weaver

needs to bend forward to perform the task easily. Thus, pit looms with warp chained over a ditch are invented to let

the weaver have his or her legs positioned below and leveled with the loom.

Back Strap Looms

Back Strap Looms are well recognized for their portability. The one end of this loom type is secured around the waist

of the weaver and the other end is attached around a fixed thing like door, stake, or tree. Pressure applied can be

customized by just bending back.

Frame Looms

Frame looms almost have the similar mechanisms that ground looms hold. Frame Loom was made of rods and

panels fastened at the right angles to construct a form similar to a box to make it more handy and manageable. This

type of loom is being utilized even until now due to its economy and portability.

Rigid Heddle Looms

Rigid Heddle Loom is the crisscross manifold loom types. The back strap looms and frame looms fall under this type.

This one normally features one harness, with its heddles attached in the harness. The yarn or thread goes in an

alternate manner all the way through a heddle and in the gap between the heddles. In this way, lifting the harness

also lifts half of the threads and letting down the harness also drops the same threads. Strands leading through the

gaps between the heddles stay in position.

Foot-treadle Floor Looms

Nowadays, hand weavers are likely to employ looms having no less than 4 harnesses. With every harness featuring a

set of heddles wherein wool can be strung, and by lifting the harnesses in diverse arrangements, a multiplicity of

designs are created. Looms having a couple of harnesses similar to these are applied for knitting tabby, the

unvarying weave textiles.

Haute Lisse and Basse Lisse Looms

These are generally employed for knitting conventional tapestry. Haute lisse has the yarn or thread hung straight up

between 2 spools. The basse lisse loom has the warp thread stretched out horizontally between spools.

Shuttle Looms

It is the key component of the loom along with the warp beam, shuttle, harnesses, heddles, reed, and take up roll. In

the loom, yarn processing includes detaching, battening, alternative, and taking-up operations.

Shuttleless Looms

Because the shuttle can cause yarns to splinter and catch, several types of shuttleless looms have been developed.

These operate at higher speeds and reduced noise levels.

Some of the common shuttleless looms include water-jet looms, air-jet looms, rapier looms, and projectile looms.