- Created: 17-01-22
- Last Login: 17-01-22
Warp knitting is a process in which the yarn is knitted up wards instead of a single row, following the adjacent columns known as wales. In warp knitting the total number of individual yarns is equal to the total stitches in a row. Warp knitting is done only by a machine, not by hand.
Warp knitting comprises many kinds of fabrics, such as raschel knits, tricot, and milanese knits. Tricot is usually used in lingerie making. Milanese is firmer, stable, smoother and costly than tricot, so it is utilized in high-end lingerie. Raschel knits are not so stretchable and are usually bulky, so they are normally used in making unlined material like jackets, coats, dresses and straight skirts.
History of warp knitting
Two names, William Lee and Karl Mayer are considerably related with the commencement of warp knitting. In 1589 William Lee applied for patent of his first machine for making knitted articles, in that way he laid the foundations for mechanical manufacturing and making the technical base to develop warp knitting technology.
In 1947, the insightful entrepreneur and mechanic, Karl Mayer showed off first warp knitting loom. The FM 48 was compiled two guide bars, and with bearded needles, attained a speed of 200 rpm. It marked the starting of technical era in pioneering leaps in the field of warp knitting.
Karl Mayer, in 1953 launched his company's first raschel loom into the factories. These warp knitting machines was working with upto four guide bars, used a four-roll take up system to allow fabric beams alterations without stopping the machine. It had a pattern-box with pattern discs or chain elements. The technology of these high-performing warp knitting machines were enhanced from one generation to the other, considering to improvise the product technology, equipping for added facilities like blind lap tools for producing knitted plisse, or sinkers with two pieces, and easily movable sinkers or pattern pressers.
The market witnessed inventions of new machines in the year 1954, the first elastic raschel machine and first tulle raschel knitting machine. In 1955 'Super Garant' series marked its name on the market. 1956 saw the first warp knitted lace machine, featuring 12 guide bars. First curtain raschel machine was introduced in 1958 and first carpet raschel machine in 1959. The success story continued in 1967 with a launch of the first fall plate multibar raschel machine and jacquard raschel machine weft insertion, along with other series. Following gradual developments led more diversity into the product range of lace raschel machines. A significant move in this process was the execution of the jacquard theory in warp knitting.
The lace raschel machines were working with nearly 57 guide bars by the year 1981. This series was first ever set with an electronic control system. In the starting of 80s, the summator, an electromechanical pattern guide bar control was introduced. The summator included slide elements, featuring defined curves on the end surfaces. Now, a pattern control computer conquest the work of supervising the pattern guide bars.
For a long period this technology was followed in the 'Jacquardtronic' and 'Textronic' series of lace raschel machines, with up to 78 guide-bars. Alike these developments, enhance also had been witnessed on the ground of automatic warp knitting machines.
In 2003, the new generation machines in the warp knitting were displayed at ITMA, Birmingham. The machines were equipped with individual motors to feed thread, fabric take-up and rolling-up, with all easy navigation. All machines had network systems with latest computers. The computer merges a motion control and a PLC for machines sequence control.
The user can operate knitting machine through Internet and intranet communication. Among the others, one computer is using ALC's 'ProCad' software, which guarantees well-organized pattern creation and error free online connection to machines. In addition, ALC software PROFAB and PDA computer also presents output data management facilities.
Two next generation technologies are introduced in the field warp knitting. The HKS3-M knitting machine complies continuous thread supervising, utilizing the scanning system and Protechna, an independent thread stabilization system for loose threads, and the roll-ups. It works on the base of specific and constantly variable selection of stitch range, featuring continuous winding tension and tremendously uniform package structure excluding complicated gear-wheel changes.
knitting, production of fabric by employing a continuous yarn or set of yarns to form a series of interlocking loops. Knit fabrics can generally be stretched to a greater degree than woven types. The two basic types of knits are the weft, or filling knits—including plain, rib, purl, pattern, and double knits—and the warp knits—including tricot, raschel, and milanese. In knitting, a wale is a column of loops running lengthwise, corresponding to the warp of woven fabric; a course is a crosswise row of loops, corresponding to the filling.
Most filling knits can be made by hand or machine, although commercial fabrics are generally machine-made. Basic stitches are the knit stitch, a loop passed through the front of the preceding loop, and the purl stitch, drawn through the back. Some filling knits are fragile because of the dependency of each loop in a vertical row on the stitch next to it. Runs can occur when one loop breaks, releasing other loops in the same row. Filling knits have the greatest amount of stretch in the crosswise direction. The plain knits, also called flat knits, have a flat surface, with short, horizontal loops visible on the back. When produced by hand knitting, this structure is called stockinette. Pile-surfaced fabrics produced by variations of the plain knit include velour and fake furs. Rib knits have pronounced lengthwise ribs formed by wales alternating on both sides of the fabric. These knits are fairly heavy, have good elasticity, and are more durable than the plain knits. Purl knits have horizontal ridges running crosswise on both the face and the back of the fabric, making them reversible. Pattern knits, such as those of fisherman knit sweaters, are produced by varying the manner in which the knit and purl stitches are used. Because the knit stitch tends to advance and the purl stitch to recede, a variety of patterns can be made by adding, dropping, alternating, or crossing stitches.
Knitted elastic is made by knitting the fibers together. Knitted elastic tends to be softer than braided or woven elastic, and it retains its width when stretched. It also works well even when pierced by needles, so it’s a good choice for sew on applications. It rolls more than woven elastic, but less than braided elastic. Since this elastic is softer, it’s suitable for light to midweight fabrics, but doesn’t have the grip needed for heavier fabrics. With knit elastic, I may cut the elastic slightly shorter than the finished measurement in order to have it grip properly, particularly when I use it for waistbands or bra bands.
Also referred to as non-roll elastic, woven elastic is usually the firmest of the three basic elastic types. It retains width as it is stretched, and is suitable for sew on applications as well as use in casings. Because it tends to be very firm, it is also suitable for heavier weight fabrics. I generally don’t cut woven elastic with much negative ease, because it will pull too much. In other words, if I’m using it in a waistband, I’ll cut the elastic to the body measurement where the waist hits, not any less.
All About Fold-Over-Elastic (FOE) and How to Sew It
In developing our Tropo Camisole pattern it feels like we’ve sewn enough fold-over elastic (FOE) to reach to the moon and back! We’ve assembled here everything we’ve learned about FOE along the way to help you get started with sewing your own FOE!
What is FOE?
FOE stands for Fold-Over-Elastic. It is a lightweight elastic that has a crease down the middle of it. It often has one shiny side (usually considered the right side) and one matte side (usually considered the wrong side) and can be found in a variety of colors and a variety of patterns. The crease allows you to fold the elastic perfectly in half.
FOE can be found in a variety of qualities and you may find some are soft while some are scratchy (particularly metallic colors). Some FOEs have better recovery than others (recovery is how well it springs back after you stretch it). Some FOEs are thicker than others. Some FOEs have more stretch than others.
When can I use FOE?
Fold-over elastic is most commonly used in garment construction to bind the edge of a garment and is particularly used on knits because the elastic-bound edge stretches. This is a clean edge finish. For our Tropo Camisole pattern we use FOE as an edge finish and as straps.
FOE on the edge of a garment finishes the edge at the width it is cut (meaning no fabric is lost to a seam allowance or folding under) so if you want to finish an edge with FOE but your pattern instructions call for a different edge finish, make sure you trim away the excess fabric before applying your FOE. Likewise, if your pattern calls for a FOE finish but you want to fold your edge under or sew on a facing, make sure you add a seam allowance to your pattern.
What size is FOE?
Fold-over elastic comes in a variety of sizes usually ranging from 3/8″ to 1″. 5/8″ FOE is the most common. The width refers to the full width of the elastic so when you sew it to the edge of your garment it will finish at 1/2″ the labeled width.
TO DESIGN A sports bra is to design for a constantly moving target. Breasts rise and fall with every jump. Run forward and they arc like a figure eight. “Breast tissue movement goes in many ways,” says Nicole Rendone, a Nike designer who spends most of her time engineering bras to mitigate those movements. “The number of components that go into a high-support bra is immense.”
Nike’s high-support bras can include upwards of 40 parts—things like supportive straps, underband elastic, and stabilizers hidden in the exterior fabric panels—all designed to create stability without squishing what's inside. Which is why Nike’s newest sports bra, the Fe/Nom, seems like an architectural anomaly. The whole thing consists of two pieces of fabric stitched together. The secret? It's made from Flyknit, the material best known for Nike’s kicks.
First introduced in 2012, Flyknit combines weaves of various tightness to create fabric that's simultaneously flexible and sturdy. On Nike's shoes, the weave is looser where the foot needs less support (near the toes) and tighter where it needs more (on the sides). The result is a fitted, unibody upper without extra stitching, and a shoe that feels more like a sock.
The Fe/Nom uses the same technique. It’s not unibody—the front and back are stitched together—but the bra functions like a single piece of fabric with six different weaving zones. The tightest stitch is reserved for the underband, which carries most of the load. The back of the bra uses a more open stitch to create more flexibility and ventilation. Each of the black lines on the bra represent a “lockdown” zone, where the knit is much tighter and more supportive, sort of like a fabric underwire.