ieee 1. WEAVING nitive man for making m Bis4 and baskets from grass and recds log, | began with the invention cf the technique | The crude method used by the discovery of the art of weaving tliongh the actual tox of spinning, When and how did it start? History does not felt tribes to fasten together the shins which they used to protect Henihe Primitive looms were built around the horizontal tree branche: hold a group of threads known as the warp. The lower onc and lifted repeatedly to pass the filling yarns under and ov at the bottom allowed better control of the warp tension. 1. position for easy interlacing. With due course of time, han advancement of technology these were replaced by elaborated technique of interlacing the yams remained the same. The huge an minutes which our ancestors took days and; months - - a ee cae Weavingiis the technique of fabric construction in which two sets of fhezaed fay terlace a right angles to produce cloth. The specific manner of interlacing is avs i which the sets of threads are interlaced, determines to a great extent the characteris! .. The two sets of threads are — warp threads and weft threads. : 1. Warp threads : The warp threads are the length-wise threads running with the selvedge from the back to the front of the loom. Itis the thread put first in the loom which makes the foundation ofthe loth. Therefore, warp threads are given extra twist during spinning for adding strength but little stretdh. . Weft threads : The threads running across the cloth from one finished edge to the other are called filling threads or weft threads. Weft threads are woven in the warp threads with the help of a shuttle from left to right and back again, over and over again along the length of the warp threads. ‘The weft threads have to tolerate Jess strain during weaving, therefore, they may not be as strong as warp threads and may have some stretch when fabric is pulled width wise. 3. Selvedge : The finished edges formed by the weft threads form the selvedge. These edges do not ravel because of the loop formed. Depending upon the weaving process, the selvedge can be very tight or smooth and similarly woven as the rest of the cloth. The width of the selvedge is 14" to". art | toll us but the thread was used even by Nomadic | hemsolves from the ravages of Sun and cgig s, which were used as cross bar jy | dof the warp was tied to stones on the groung | ier them. A second cross bar added as a weighy ater the warp yarns were fastened in upright d operated looms came into being. With the power operated looms but the fundamenta} d powerful looms today accomplish in xn ABASIC LOOM Principle: As lifting of each warp yam for passing the weft threa the weavers devised a method to lift a number of alternate ‘warp yarns at'a time while the same number was left below This formed a shed and it was easy to pass the weft thread through it. Thus a simple l consists of two frames called hares ie Ardy dae ses Which hold the wires wit ‘can also be used in place of wires. The warp yams passthrough yy ae pea enstione tteet pal irowgheyein pe ust frame and even ones through the eyelets of the second fee When the © ama, The st a dwar yams are lied yp anda shed is formed bene the odd and even fist one goes down, the opposite stan eesse4 through it. Then the second frame lifted up and th it Such faster veving sy ched oes eain he shut carving wet yea ieee a te Such ister weaving using shed formation was fst developed cg > a eae are lifted in special pattems, the patterned cloth is mada Snzontal looms. Ifthe warp threads id was a slow and tiresome task,parts Asimple loom (Fig 4 -2) consis 1, The WAP BEANE The Warp he cads are wrapped in parallel ines ands other Beam called the cloth roi. ii tS Of the follow paris 4 bar place 7 diel ea the back of the loon on which tho warp he front of the loom where they aro attached Hedstos Reo Warp yam : Woven cloth Cloth roll Warp beam Filling yarn i res with eyélets in the centre through which the warp threads pass towards the warp beam (Fig 4.3). For domestic weaving, the heddles are made from thick and strong cotton yarn. Eye for warp yam B. 3. Harness Harness is a rectangular frame to which heddles are attached and held in position. It is also called the heddle frame. Harness is the important part of the loom as it controls the upward = downward shifting of the warp threads to form the desired type of sheds so that the shuttles are passe through them to Teun the required pattem, The number of hamesses varies depending upon the Sobre construction i.e. the weave e.g, two harnesses are required for plain weave, three or more for twill weave and five to twelve for satin weave. i : a 4. The shuttle : Shuttle holds the filling yam (Fig 4.4) and is moved forxerd a beckae through the shed to form the pattem. Number of shuttles depends upon the number of colo shed to . Pattern,athe, — shutilo Le Yorn corning ow — Bobbin ‘of shultlo from a holo bin v4.4. A Shuttle with bobbin, : a rm the comb like structure (Fig 4.5). is iti Ilel to the harness. The spaces | located in front of the hamess towards the cloth roll in a ae eee ae Hs {Source the ite aro called dents, The warp threads pass tntous a the warp yams ib | aeatse This Frame is pushed forward each tne after passing the SHUNT ON as separated and_ | compactly press back the filling yarns in position. The reed also keep: | ents their entangling. 5. The reed : It isa wooden frame containing wires to fo pre’ ‘Teeth of the reed which keep warp yarns apart Fig. 6. The cloth beam or cloth roll: It is located at the front of the loom on which the fabric is rolled as it is constructed. It also supports the warp yarns at the front side of the loom. Steps in Weaving Process Weaving process is completed in four steps : 1. Shedding : raising the required warp yams by using the harness and forming the shed. 2. Picking : Inserting the shuttle containing filling yarns through the shed, 3. Battening : Pushing the filling yams in place with the hel It is also called beating up. 4, Taking up and letting off : Winding the finished fabri jiauees Gan ia eae fabric on the cloth beam and releasing more of Ip of reed to form the compact structure. Sareeques of Fabric Construct ju 7 Picking : As the required munber af % : Wwanp yarn quale cartying the filling MD Yarns is raised yam is passed through sh the shed formed. A yams from one side to the other is cated a i Seen ; io ithrough the shed depending upon the kind of loom beiny Bu ashutile loom, a shuttle carrying th ae ea a a line te is used ty -s ype of loom which is very effective and easy to operate but tho deed zefimes causes abrasion on the warp yarns while passing through a os x eyare also noisier and slow as compared to many newly invented looms, To overcome these disadvantages, shuttle-less looms have been developed + iques for picking 1.¢. for passing of filling yarns. Missile or projectile looms ajectiles and have a speed of 300 picks per minute. Rapier looms use a device called r ader sword for thrusting) for this purpose and operate at a speed of 200-260 pi ag watersjet looms in which pre-measured length of filing yam is carried across th: ster at a high speed of 600 picks per minute. Air jet looms use a jet of air to pro; rough the shed at a rate of 600 picks per minute. 3. Battening : Battening frame resembles a comb and is called reed. The warp yarns p: itscomb like teeth. After each picking operation, the reed automatically moves forward, push: exh illing yarns against the fabric. Therefore, this operation is also called beating up. In early he _ beating up was done by iron combs. Battening operation gives the fabric a firm and compact 4, Taking up and letting off : With each shedding, picking and battening operation, | constructed fabric is wound on the cloth beam. This process is known as taking up. At the same time | warp yams are released from the warp beam. This process is called the letting off. In the tr al | kandloom, this was done by shifting the harness. The length of the warp let-off must be balanced by | ‘ubric take-up to maintain the required tension on the warp yarns. Wh the first operate phiquess are sin