Textile-Weft and Warp Knitting

Weft and Warp Knitting Differences

Weft and Warp knitting are technical terms that describe two different types of knitting used by either machine or hand. They refer to the widths and lengths of the thread and how many needles are used.  Knitting is typically done by hand, although some machines are used today.  These terms are technical terms mostly used when discussing machine knitting, although weft knitting can be done by hand, too. There are many differences between weft knitting and warp knitting, and since many knitters don’t commonly know these terms, we’ll discuss them here.  There is a lot to learn about weft and warp knitting, so continue reading to expand your knowledge of the ancient art of knitting.

Weft Knitting Versus Warp Knitting

Weft and warp knitting are completely different knitting techniques that result in two different types of fabrics.  The most obvious difference in these two techniques is that weft is a yarn that runs back and forth, while warp is a yarn that runs up and down. Due to these different techniques, the finished product is entirely different, too.  For example, weft knitting can produce shaped garments and highly drapeable fabrics while warp knitting produces only coarse yardage.

Weft Knitting

Weft knitting, which can be done by hand or machine, uses a continuous thread to form courses and loops in the fabric.  This technique can produce either fabric yardage or shaped garments such as circular fabrics.  Due to the fact that it uses one continuous thread to create a finished product, it is very hard to unravel and creates a very elastic and thin fabric.  However, this fabric is more likely to shrink than fabric created using warp knitting, and needs to be washed and dried by hand rather than in a machine.

While weft knitting offers many more options in terms of finished products, the technique is generally more complicated and takes a longer time to complete.

There are three fundamental stitches used in weft knitting, which are:

•    Plain knit

•    Rib knit

•    Purl knit

This knitting technique creates many of the classic knitting looks you’ve come to recognize, and is more likely used by hand knitters everywhere.

Warp Knitting

On the other side of the knitting spectrum is warp knitting.  Usually knitting machines are used for this technique. It is much simpler and faster than weft knitting, which makes it more likely for commercial knitting fabrics. Another advantage to warp knitting is that the finished fabric can be washed in a machine with much less risk of shrinkage.

Unlike with weft knitting, each needle on a knitting machine uses it’s own loop of yarn to form parallel rows.  These rows and loops are interlocked to form fabric like the knitted fabrics you can find in stores.  Due to the restrictions of this technique, warp knitting is only used for fabric yardage rather than shaped and fitted garments. Very large widths of fabric can be created using warp knitting.  In addition, the fabrics are generally coarse, and thicker than those produced using weft knitting.

There are six fundamental stitches used in warp knitting, which are:

•    Tricot knit, which is soft and less prone to wrinkles.

•    Milanese knit, which can be recognized by the rib pattern on the face.

•    Simplex knit, which is pretty thick and dense.

•    Raschel knit, which creates nets, veils, and lace.

•    Ketten raschel knit, which creates a raised pattern on the fabric.

•    Crochet knit, which is the basic hand-crochet stitch.

While these terms are most commonly used to refer to machine knit fabrics, warp and weft knitting can be used to describe some hand-knit pieces as well.  In fact, as mentioned above, weft knitting can be done by either machine or hand.  Knowing these terms can help you choose which techniques you need to use for your project, since they result in entirely different fabrics.  If you are looking for a thinner, more elastic fabric, or need to shape your project as you go, weft knitting is the way to go. However, if it is more important to you to have a fabric that can go in the washing machine, warp knitting will give you the finished product you are looking for.  Whichever way you go, it is important to know the differences between weft and warp knitting if you are creating commercial knitting fabrics.

Definition of Warp Knitting | Definition of Weft Knitting | Comparison Between Weft and Warp Knitting

What is Weft Knitting?

In case of weft knitting, a horizontal raw of loops can be made by using one yarn, where the yarn runs in the horizontal direction.

What is Warp Knitting?

In case of warp knitting, each loop in horizontal direction is made from a different yarn and the number of yarn which is used for producing fabric is at least equal to the no. of loops in the horizontal raw. It’s should be noted here that, the used yarn run through in the vertical way.

Difference Between Warp Knitting and Weft Knitting:

SL No.	Warp Knitting	Weft Knitting
01	Here, the used yarn runs in the horizontal direction.	Here the used yarn runs in the vertical direction.
02	Warp knitting is elastic to the length.	This type of knitting is elastic to the width.
03	It has less shrinkage than weft knitting.	It has higher shrinkage than warp knitting.
04	Used yarns are supplied from the beam.	Here, used yarns are supplied from the cone.
05	Warp knitted fabric is too much perfect for dry wash.	Weft knitted fabric is perfect for hand wash.
06	Warp knitting is suitable for producing coarse fabric.	This type of knitting is perfect for producing thin fabric.
07	Here, the loops are produced to the length of fabric.	Here, the loops are produced to the width of fabric.
08	Elasticity is less for warp knitted fabric.	Higher elasticity for weft knitted fabric.
09	More courses are required for each pattern raw.	Here, course is equal to the pattern.
10	Here, at least one yarn is required for each knitting needle.	Here, any number of knitting needle is required for one yarn.
11	It’s easy to produce any kinds of fabric design by using warp knitting process.	It’s tough to produce any kinds of fabric design by using this knitting process.

What is the difference between warp knitting and weft knitting and how to identify if the fabric is made by warp or weft?

If possible, please add pictures while explanation as it would be easier to understand.

Weft and Warp knitting are technical terms that describe two different types of knitting used by either machine or hand. They refer to the widths and lengths of the thread and how many needles are used.

Weft Knitting vs Warp Knitting

Weft and warp knitting are completely two different knitting techniques that result in two different types of fabrics. The most obvious difference in these two techniques is that weft is a yarn that runs back and forth, while warp is a yarn that runs up and down. Due to these different techniques, the finished product is entirely different, too. For example, weft knitting can produce shaped garments and highly drapeable fabrics while warp knitting produces only coarse yardage.

Warp Knitting

Knitting machines are used for this technique. It is much simpler and faster than weft knitting, which makes it more likely for commercial knitting fabrics. Warp knitting represents the fastest method of producing fabric from yarn. It differs from weft knitting in that each needle loops its own thread. The needles produce parallel rows of loops simultaneously that are interlocked in a zigzag pattern.

Fabric is produced in sheet or flat form using one or more sets of warp yarn. The yarns are fed from warp beams to a row of needles extending across the width of the machine. Another advantage t warp knitting is that the finished fabric can be washed in a machine with much less risk of shrinkage.

Unlike with weft knitting, each needle on a knitting machine uses it’s own loop of yarn to form parallel rows. These rows and loops are interlocked to form fabric like the knitted fabrics . Due to the restrictions of this technique, warp knitting is only used for fabric yardage rather than shaped and fitted garments. Very large widths of fabric can be created using warp knitting. In addition, the fabrics are generally coarse, and thicker than those produced using weft knitting.

There are six fundamental stitches used in warp knitting, which are:

• Tricot knit, which is soft and less prone to wrinkles.

 • Milanese knit, which can be recognized by the rib pattern on the face.

 • Simplex knit, which is pretty thick and dense.

 • Raschel knit, which creates nets, veils, and lace.

 • Ketten raschel knit, which creates a raised pattern on the fabric.

 • Crochet knit, which is the basic hand-crochet stitch.

Raschel

Coarser yarns are generally used for raschel knitting, and there has recently been interest in knitting staple yarns on these machines. In the Raschel machine, the needles move in a ground steel plate, called the trick plate. The top of this plate, the verge, defines the level of the completed loops on the needle shank. The loops are prevented from moving upward when the needle rises by the downward pull of the fabric and the sinkers between the needles. Guide bars feed the yarn to the needles.

In a knitting cycle, the needles start at the lowest point, when the preceding loop has just been cast off, and the new loop joins the needle hook to the fabric. The needles rise, while the new loop opens the latches and ends up on the shank below the latch. The guide bars then swing through the needles, and the front bar moves one needle space sideways. When the guide bar swings back to the front of the machine, the front bar has laid the thread on the hooks. The needles fall, the earlier loops close the latch to trap the new loops, and the old loops are cast off. Raschels, made in a variety of forms, are usually more open in construction and coarser in texture than are other warp knits.

Tricot

Tricot, a warp knit made with two sets of threads, is characterized by fine ribs running vertically on the fabric face and horizontally on its back. The tricot knitting machine makes light fabrics, weighing less than four ounces per square yard. Although approximately half of the tricot machines in current use make plain fabrics on two guide bars, there is increasing interest in pattern knitting. In this type of knitting, the warp-knitting cycle requires close control on the lateral bar motion, achieved by control chains made of chunky metal links.

Special effects in warp knits

The scope of warp knitting has been extended by the development of procedures for laying in nonknitted threads for colour, density, and texture effects (or inlaying), although such threads may also be an essential part of the structure. For example, in the form called “zigzagging across several pillars,” the ground of most raschel fabrics, the front bar makes crochet chains, or “pillars,” which are connected by zigzag inlays.

An extension of conventional warp knitting is the Co-We-Nit warp-knitting machine, producing fabrics with the properties of both woven and knitted fabrics. The machines need have only two warp-forming warps and provision for up to eight interlooped warp threads between each chain of loops. These warp threads are interlaced with a quasi weft, forming a fabric resembling woven cloth on one side.

Other interlaced fabrics

Net and lace making

The popularity of handmade laces led to the invention of lace-making machines. The early models required intricate engineering mechanisms, and the development of the modern lace industry originated when a machine was designed to produce laces . In the Heathcot, or bobbinet, machine, warp threads were arranged so that the threads moved downward as the beams unwound. Other threads were wound on thin, flat spools or bobbins held in narrow carriages that could move in a groove or comb in two rows. The carriages carrying the bobbins were placed on one side of the vertical warp threads and given a pendulum-like motion, causing them to pass between the warp threads.

The warp threads were then moved sideways, so that on the return swing each bobbin thread passed around one of them. Then the warp threads moved sideways in the opposite direction, thus completing a wrapping movement. In addition, each row of bobbins was moved by a rack-and-pinion gearing, one row to the left and one to the right. As these movements continued, the threads were laid diagonally across the fabric as the warp was delivered.

Many types of machine-made laces are made, frequently with geometrically shaped nets forming their backgrounds. Formerly made only of cotton, they are now frequently made from man-made fibre yarns. Bobbinet lace, essentially a hexagonal net, is used as a base for appliqué work for durable non-run net hosiery, and, when heavily sized, for such materials as millinery and veilings. Barmens lace has a fairly heavy texture and an angular pattern; flowing lines, heavy outline cords, and fine net backgrounds are not usually made on Barmens machines.

Weft Knitting

Weft knitting can be done by hand or machine. This technique uses a continuous thread to form courses and loops in the fabric. This technique can produce either fabric yardage or shaped garments such as circular fabrics. Due to the fact that it uses one continuous thread to create a finished product, it is very hard to unravel and creates a very elastic and thin fabric. However, this fabric is more likely to shrink than fabric created using warp knitting, and needs to be washed and dried by hand rather than in a machine.

While weft knitting offers many more options in terms of finished products, the technique is generally more complicated and takes a longer time to complete.

There are three fundamental stitches used in weft knitting, which are:

 • Plain knit

 • Rib knit

 • Purl knit

source : Weft and Warp Knitting Differences

The type of stitch used in weft knitting affects both the appearance and properties of the knitted fabric. The basic stitches are plain, or jersey; rib; and purl. In the plain stitch , each loop is drawn through others to the same side of the fabric. In the rib stitch, loops of the same course are drawn to both sides of the fabric. The web is formed by two sets of needles, arranged opposite to each other and fed by the same thread, with each needle in one circle taking up a position between its counterparts

in the other. In a 2:2 rib, two needles on one set alternate with two of the other. The interlock structure is a variant of the rib form in which two threads are alternately knitted by the opposite needles so that interlocking occurs. In the purl stitch , loops are drawn to opposite sides of the fabric, which, on both sides, has the appearance of the back of a plain stitch fabric. Jacquard mechanisms can be attached to knitting machines, so that individual needles can be controlled for each course or for every two, and complicated patterns can be knitted. To form a tuck stitch, a completed loop is not discharged from some of the needles in each course, and loops accumulating on these needles are later discharged together. The plaited stitch is made by feeding two threads into the same hook, so that one thread shows on the one side of the fabric and the other on the opposite side. A float stitch is produced by missing inter-looping over a series of needles so that the thread floats over a few loops in each course.

circular knitting machine

flat knitting machine

Knitting machines can be flat or circular. Flat machines have their needles mounted in a flat plate or needle bed or in two beds at right angles to each other and each at a 45° angle to the horizontal. The knitted fabric passes downward through the space between the upper edges of the plates, called the throat. In the knitting process, the needles are pushed up and down by cams attached to a carriage with a yarn guide, which moves over the length of the machine. The width of the fabric can be altered by increasing or decreasing the number of active needles, allowing production of shaped fabrics, which when sewn together make fully fashioned garments. Although flatbed machines are suited

for hand operation, they are power driven in commercial use, and, by selection of colour, type of stitch, cam design, and Jacquard device, almost unlimited variety is possible. The cotton frame, designed to knit fine, fully fashioned goods, shaped for improved fit of such items as hosiery and sweaters, is fitted with automatic narrowing and widening devices.

Circular machine needles are carried in grooves cut in the wall of a cylinder, which may be as small as 1 cm (0.4 inch) in diameter and as large as 1.5 metres (5 feet). Some circular machines have two sets of needles, carried in concentric cylinders, so that the needles interlock. During the knitting operation the butts of the needles move through cam tracks, the needles sliding up and down to pick up yarn, form a new loop, and cast off the previously formed loop. In the least complicated of these machines, yarn is supplied from one package, each needle picking up the yarn once per revolution of the cylinder. Modern machines may have as many as 100 feeders, allowing each needle to pick up 100 threads per revolution. Both latch and spring needles are used, with the former more common. Modern, large, circular, plain or jersey machines having 90–100 feeders are frequently used to produce medium-weight fabric. Small bladelike units, or sinkers, are inserted between every two needles to engage and hold the completed fabric, preventing it from riding up with the needles as they are lifted to form new stitches. Machines may be fitted with pattern wheels controlling needle action to produce tuck and float stitches, and a Jacquard mechanism may also be attached. Stop motions are essential to stop the machine when a thread breaks. Because yarn tension affects fabric uniformity, various tension controllers have been devised. An alternative method, positive feed, which feeds precisely measured amounts of yarn into the machine, is now considered more satisfactory.

Circular rib machines consist of a vertical cylinder, with needle slots on the outside, and a horizontal bed in the form of a circular plate or dial with needle slots cut radially, so that the two sets of needles are arranged at right angles to each other.

Seamless hosiery, knitted in tubular form, is produced by circular knitting machines. Modern hosiery machines, such as the Komet machine, employ double-hooked needles directly opposite each other in the same plane to knit the leg and foot portions, the heel and the toe. The toe is later closed in a separate operation. In the Getaz toe, the seam is placed under the toes instead of on top of them.

Underwear fabrics are usually knitted on circular machines, and—except for fully fashioned underwear, tights, and leotards, which are knitted to pattern and sewn together—underwear making is a cut, make, and trim operation. Tights or panty-hose are a combination of hosiery and underwear and can be fully fashioned. Seamless panty hose are made on circular hose machines modified to make very long stockings with open tops, two of which are cut open at opposite sides and seamed together front and back. The wearing quality and fit of modern panty hose have been greatly improved with the development of stretch nylon and spandex, and greater variety has been introduced with the development of texturized yarn.

Much hosiery is finished by washing, drying, and a boarding process in which the hosiery is drawn over a thin metal or wooden form of appropriate shape and pressed between two heated surfaces. The introduction of nylon fibre led to the development of a preboarding process, setting the loops and the fabric in the required shape before dyeing and finishing. The article, fitted on a form of appropriate shape, is placed in an autoclave or passed through a high-temperature setting unit. Fabric treated in this way does not distort during dyeing.

Circular knitting machines can be adapted to make simulated furs. One type intermeshes plush loops with the plain-stitch base fabric then cuts the loops, producing a pile. A more common method forms the pile with a carded sliver. A plain-stitch fabric is used as the base and loose fibres from a sliver, fed from a brushing or carding device, are inserted by a V-shaped claw, forming the pile. Pile depth is determined by the length of the fibres in the sliver.

One of the most sophisticated knitting machines incorporates electronic selection of sinkers in a Jacquard circular knitting machine.

Weft knitting.

Weft knitting uses one continuous yarn to form courses, or rows of loops,across a fabric. There are three fundamental stitches in weft knitting: plain-knit, purl andrib. On a machine, the individual yarn is fed to one or more needles at a time. Weft Knitting machines can produce both flat and circular fabric. Circular machines produce mainly yardage but may also produce sweater bodies, pantyhose and socks. Flatbed Machines knit full garments and operate at much slower speeds. The simplest, most common filling knit fabric is single jersey. Double knits are made on machines with two sets of needles. All hosiery is produced as a filling knit process.

Weft knitting is a knitted piece of fabric where the stitches run from left to right horizontally across the fabric. It is usually knitted with one piece of yarn, and can be made either by hand or using a knitting machine. Weft knitting is the most common form of knitting as it is simpler than warp knitting, the other form of knitting.

Weft knitting was the first type of knitting invented, Stockinette stitch is the most common form of stitch used and it was first discovered in artefacts from as early as the 11th Century. Many other stitches can be used in weft knitting such as Purl, Double knitting, and patterns such as Cable, Fair Isle and Aran can be achieved using different yarns in different colours and weights.

The knitting machine was invented to speed up the manufacturing process of knitted products. It also meant that patterns were more calculated and symmetrical. It also meant that less mistakes were made as it is harder to drop stitches and cause ladders. Nowadays many of the knitted garments that are mass produced are produced in factories using knitting machines.

Types of Weft knitting include Jersey, Double Knit, Circular Knitting, Fair Isle and Cable knit. All of these knits are generally produced using a knitting machine as a finer gauge, more delicate fabric can be produced but hand knitting is still used, mainly as a hobby nowadays.

Sample, Rib weave Warp: twined cotton, black Weft: thick

Properties of Weft Knitting

·         Very elastic

·         Warm to wear

·         Comfortable

·         Shrinks easily

·         Different properties can be achieved depending on the yarns used

·         Can stretch out of shape easily

·         Does not fray

·         Unravels when cut

·         Curls up at the edges

·         Various colours/patterns can be achieved

·         Good Insulator

End Uses of Weft Knitting

·         Underwear

·         Hosiery

·         T-Shirts

·         Sportswear

·         Baby Clothes

·         Pyjamas

·         Knitwear such as Jumpers, Scarves, Hats and Gloves

Warp Knitting.

Warp knitting represents the fastest method of producing fabric fromyarns. Warp knitting differs from weft knitting in that each needle loops its own thread.The needles produce parallel rows of loops simultaneously that are interlocked in a zigzag pattern. Fabric is produced in sheet or flat form using one or more sets of warp yarns. The yarns are fed from warp beams to a row of needles extending across the width of the machine (Figure 9b). Two common types of warp knitting machines are the Tricot And Raschel machines. Raschel machines are useful because they can process all yarn types in all forms (filament, staple, combed, carded, etc.). Warp knitting can also be used to make pile fabrics often used for upholstery

Weft vs Warp

Weft and warp are terms that come with knitting. Weft and warp are knitting terms that relate to the widths and lengths of threads.

“Warp” is a series of threads that run from the front to the back, and “weft” is a series of threads that run in a pattern through the warp. Weft is a yarn that runs back and forth whereas a warp is that which run up and down.

Continuous yarn is used in weft knitting for forming courses and rows of loops. Weft knitting comes in three fundamental stitches like: plain knit, rib knit, and purl knit. Weft knitting produces both circular as well as flat fabrics.

The warp knitting comes in six stitches like: Tricot Knit, Milanese Knit, Simplex Knit, Raschel Knit, Ketten Raschel Knit, and Crochet Knit.

Most of the weft knitting is done by hand, and the machine is rarely used. On the other hand, warp knitting is mainly done by machine and not by hand. Unlike weft knitting, each needle loops into its thread. With this loop, the weft knitting produces parallel rows, and the loops are also interlocked.

When comparing the two, the fabrics having weft knitting are highly drapeable and elastic. The weft knitted fabric, which is produced in tubular or flat form, is not that easy to unravel.

In warp knitting, the needles knit concurrently for all yams, and in weft knitting, the needles just knit in a series for each yam.

Warp knitting only produces yardage whereas weft knitting produces yardage as well as shaped garments. When comparing the two, warp knitting is considered to be the fastest.

Summary:

1. “Warp” is a series of threads that run from front to back, and “weft” is a series of threads that run in a pattern through the warp.
2. In warp knitting, the needles knit concurrently for all yarns, and in weft knitting, the needles just knit in a series for each yarn.
3. “Weft” is a yarn that runs back and forth whereas “warp” is that which runs up and down.
4. Weft knitting comes in three fundamental stitches like: plain knit, rib knit, and purl knit. The warp knitting comes in six stitches like: Tricot Knit, Milanese Knit, Simplex Knit, Raschel Knit, Ketten Raschel Knit, and Crochet Knit.
5.Weft knitting produces both circular as well as flat fabrics.
6.Most of the weft knitting is done by hand and the machine is rarely used. On the other hand, warp knitting is mainly done by machine and not by hand.