What are 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.
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.
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.
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.
What is 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.
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.
What is 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.
What is 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.
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.
Types of Weaving Looms
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.
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.
What is a 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.
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.
Weft Preparation for Shuttleless Weaving
- 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.
Sizing for Shuttleless Weaving
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.
Warping requirements for Shuttleless Weaving
- 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.
Winding requirements for Shuttleless Weaving
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.
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.
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.
Shuttleless Weaving
- Modern 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.
Introduction
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 war p and sized beam which consequentially gives and efficient weaving operation both qualitatively and quantitatively.Loom 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
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.
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
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.
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.
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.
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.
Electronic Control Mechanism
- 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.
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.
Minimum Down Time of Looms
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.
Production Rates of various 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 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.
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.
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.
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 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
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
Taniko Weaving
- Taniko (or taaniko), is a traditional weaving technique of the Māori of New Zealand related to "twining". It may also refer to the resulting bands of weaving, or to the traditional designs.
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.
Procedure of Tablet Weaving
- 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.
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
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.
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.
Inkle weaving is commonly used for narrow work such as trims, straps and belts.
Equipment For Inkle Weaving
- 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.
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.
Finger weaving
- 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
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.
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.
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.
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.
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.
- Projectile Looms
- Rapier Looms
- Fluid Jet Looms
- Multiphase Looms
Developments in 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.
Development of Handlooms
- 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.
Weft
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.
Warp
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.
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.
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)
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)
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.
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.
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 | Loom Types
The Different Types of Looms are :
Hand Loom
Dobby Loom
Jacquard Loom
Northrop Loom
Overview of Looms
Loom
- A 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.
Hand Looms
- The first and original 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
- They 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.
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.
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