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Home , Buttonhole (knitting), Hem (knitting), Jersey (fabric), Ribbing (knitting), Stretch fabric

CT-MMB.165

Sewing with Knit Fabric

Knits are an important part of every machines with a single bed of needles. wardrobe because they are comfortable to Fabrics such as look different on the wear and easy to care for. Because of their reverse side and their edges tend to curl. elasticity, knit garments do not require a lot Double knit fabrics are constructed on of fitting and they shed wrinkles well. Most machines with two beds of needles, back to knits do not ravel, making them quick and back. Double knits generally look the same easy to sew. Knits are versatile and can be front to back, are more stable than single seen in everything from the most casual knits, and the edge doesn’t curl. wear to the dressiest of clothing attire. They Interlock knits are made from fine come in a variety of fabrics that vary in lightweight , while other double knits texture, elasticity, content, weight, and are heavier in weight. , terry knit, and design. sweatshirt fleece are double knit but tend to curl because they have a single knit base Made from interlocking looped stitches, knit and look different from front to back. fabrics do not have lengthwise and Rib knits are created by alternating knit and crosswise yarns like woven fabrics. Instead, purl stitches in various combinations. They the interlocking loops of create may look the same or different front to back, lengthwise ribs called wales and crosswise edges don’t curl, and they may stretch 100 lines called courses. In single knits, the percent in the crosswise direction. Rib knits wales are visible from the right side of the are generally used for band trims around fabric and the courses are visible on the , armholes, and hemlines but can fabric’s wrong side. also be used for form fitting garments. Warp knits are created by inter-looping the warp yarns. They are knitted flat rather than in a tube. Tricot and raschel knits are the most common types of warp knits but look completely different because of the types of yarns used in . Raschel knit is a novelty knit with textured yarns, recognized by its lacy construction. Whereas tricot knit is a lightweight knit with lengthwise ribs on its face.

Knit fabrics are typically classified by their A single yarn or set of yarns is looped together. amount of stretch. ƒ Firm, stable knits have very little stretch Knit fabrics are either weft or warp and are handled much like woven constructed. The type of fiber used as well fabrics. These may include double knit, as the method of construction affects the sweatshirt knit, boiled , and amount of stretch in each. Weft knits raschel knit. include single knits, double knits, and rib ƒ Moderate stretch knits are those that knits and are created by inter-looping the stretch about 25 percent in the crosswise or filling yarns. Knitting can be crosswise direction. Moderate stretch done flat or in the round, creating a tube knits allow enough stretch for comfort which is often cut to form a flat fabric. but are not intended to conform to body Single knits are created by knitting contours. These may include The amount of built into the lightweight single knits such as jersey design is based on the number of inches or and warp knits such as tricot. Interlock the percentage stretch the specific knit will knits are lightweight and drapable, stretch. If the fabric has more stretch than slightly heavier than jersey knit, and recommended, the garment may fit looser. If don’t curl at the edge, making them less stretch, then the garment will fit tighter. easier to handle than jersey knit. However, runs may form on the Please refer to the stretch chart on crosswise edge. Fleece is a double- page 8. To use the gauge, avoid stretching napped knit that has a moderate along the cut edge by folding the fabric back amount of stretch. about 4 inches. Most gauges use a 4-inch ƒ Two–way stretch knits may have up to measurement to the degree of 50 and 75 percent stretch in the stretch. Place the folded 4-inch section lengthwise direction and up to 50 to 75 against the 4-inch section on the gauge and percent in the crosswise direction. gently stretch towards the right end to see if Typically used for leotards, , the fabric has adequate stretch for the and bodysuits; they can also be used pattern. If the folded edge starts to curl, you for other form fitting garments. have stretched the fabric too much. This ƒ Super stretch knits stretch 100 percent guide tells you the minimum amount of or more in both directions. stretch needed for the pattern. If the knit and latex add the extra elasticity to stretches a little beyond the mark, it is still these knits. Super stretch knits are suitable for the pattern. Generally, stable used for performance enhancing knits stretch ½ inch or less (10 percent), sportswear and ski wear. moderate-stretch knits stretch 1 to 1 ¼ inches (25 to 35 percent), super stretch and two-way stretch knits will stretch 2 or more inches in both directions (50 to100 percent). CHOOSING PATTERNS Check for fabric recovery after stretching. When the fabric is released, it should spring Patterns designed for knits generally have back to its original size. If the fabric remains fewer pieces and less shaping details, distorted, it will likely stretch out of shape making them quick to sew. Look for the with handling and wear and should be words “For Stretch Knits Only,” and always avoided. check the pattern envelope for suggested fabrics. Patterns designed for stretch knits Swimsuits and leotards require knits with have less ease built in than patterns for two-way stretch. Often, two-way stretch stable knit and woven fabrics. Facings are spandex has a greater amount of often replaced by , binding, or turned stretch in the lengthwise direction while and stitched necklines. are a more spandex has greater stretch in the suitable closure than and crosswise direction. Use the stretch gauge . If these features are not for the direction indicated on the pattern included, choose a pattern that does or one envelope. There may be separate gauges that can be adapted for them. for lengthwise stretch and crosswise stretch.

As with all knits, the greatest amount of Most patterns designed for knits will include stretch should go around the body. a stretch gauge printed on the back of the pattern envelope. Follow the guidelines for If lining fabric is required for the pattern, be recommended stretch. If the pattern does sure that it also meets the recommended not have a stretch gauge, it was likely stretch guidelines. designed for stable knit or .

2 PREPARING THE FABRIC other. If the fabric has wrinkles or is stretched to create the rectangular Washable knits tend to shrink more shape, it is not completely straight of often and to a greater degree than and should be blocked. Hold a woven fabrics. Always purchase extra steam iron about ½ inch above the yardage to allow for shrinkage. For best fabric to steam fabric in place. Let the results, wash and dry the fabric as you fabric rest until completely cool and dry would the finished garment. Washing so it will retain its shape. If the also helps to relax the fabric and surface is smaller than the amount of removes fabric sizing. Excess sizing can fabric, block the fabric in sections from cause skipped machine stitches. one end to the other. Preshrink , , lining, and other that will be used in the Layout, Cutting, and Marking garment. Generally, rib knit should not Determine if the knit has a right and be prewashed if being used as a trim. wrong side. Jersey and tricot knits have Washing softens it and makes it difficult lengthwise ribs on the right side and to cut accurately. crosswise loops on the wrong side. Most knits will curl to the right side when Blocking Knits stretched along the crosswise cut edge. Mark “grainline” by marking along a If the right side is undetectable, course near each cut end of the fabric. designate one side to be the wrong side Cut the edges of the fabric so they are by marking with chalk or tape. straight with the course. Fold the fabric so the lengthwise edges and the cut Fold the knit fabric with right sides crosswise edges are even. If the fabric together, making sure that the wales is a tubular knit or doesn’t have an open and courses are perpendicular to each edge, the fabric can be cut along a other. It may be necessary to fold small lengthwise wale or rib-line. Do not use sections at a time or cut pieces out the fold as a guide for cutting because it separately to ensure that all pattern may not be straight. pieces are cut “on grain.” If the lengthwise fold or crease remains after prewashing and steaming, it is likely to be permanent. Fold knit in such a way as to avoid the crease when cutting. Do not let knit fabric hang over the edge of the cutting table. The weight of the fabric will cause it to be distorted. Roll extra fabric up along one end to prevent fabric overhang.

Lay out all pattern pieces going the Fold knit fabric to check for straightness, and to straighten if necessary. same direction by following the “with Lay the fabric on a blocking board or on ” layout. Use fabric weights or use a similar padded surface with the ballpoint or sharp, fine along lengthwise and crosswise edges pinned allowances to secure pattern pieces for to the surface at right angles to each cutting. Be careful not to stretch fabric

3 while cutting. A rotary cutter and mat Stretch twin needles come in make cutting out knits easy and various widths and are great for eliminates movement and distortion. topstitching hems. • : For lightweight knit use There are a variety of marking methods. extra fine or polyester/ Try pins, water-soluble marking pens, cotton thread; for medium weight ’s tacks, or hard milled soap slivers. knits use an all-purpose polyester Test marking pens on scrap fabric to be or polyester/cotton thread. sure the ink can be removed before Mercerized cotton thread does not using on pieces. Mark the have as much stretch as synthetic wrong side of each garment piece with thread. Using a textured nylon tape. thread in the to sew a plain seam makes it more elastic. Textured nylon thread gives a nice NOTIONS FOR KNITS soft edge to serged seams and can also be used in the bobbin when As with any project, using the working with a twin needle. Be sure appropriate notions will help in achieving to wind bobbin slowly to prevent the best results. thread from stretching, which can • Pins: Use ballpoint pins on knit cause puckered seams in the fabric. The rounded points on these finished garment. pins separate the yarns instead of • Elastic: Elastics differ in their piercing them, creating holes in the stretch and recovery fabric. characteristics. Braided elastic • Needles: Universal narrows when stretched and can needles well on most knit lose stretch and recovery if it is fabrics. Ballpoint needles like pierced when stitched. Knitted and ballpoint pins have a rounded tip woven elastics retain their original width when stretched. Non-roll elastic is appropriate for pull-on pants and skirts. Transparent elastic works well when topstitched and can stretch up to four times in length. It can also be used to stabilize seams when not stretched. Elastic used in swim- Use a ballpoint needle with knits. wear should be chlorine resistant. that eliminates snagging, and • Interfacing: The choice of interfacing stretch needles work well to is determined by the purpose and prevent skipped stitches. If skipped the relationship to the general stitches are a problem, use a larger characteristics of the fashion fabric. needle or try a needle lubricant. All More than one type of interfacing these needles come in a variety of may be needed within the same sizes from 60 to 90. Needle size garment. Select such will depend on fabric weight. The as a fusible tricot or a stretch non- finer the fabric, the smaller the woven to stabilize areas such as needle and thread should be.

4 necklines, collars, cuffs, plackets, seams, stitch length can be shortened and buttonholes. Consider the slightly. weight, stretch, and care requirements of the knit as well as the desired finish. Since fleece does not tolerate heat well, a sew- in interfacing is recommended. To determine its compatibility, always test a swatch of fabric with the chosen interfacing before using in the garment.

SEWING TECHNIQUES Since knit fabric doesn’t ravel, seam finishes are optional. However, if the cut Seams and seam finishes for knits edges curl, the seam or sew two must stretch with the knits or broken rows of stitching ¼ inch apart and trim stitches will occur. Check the pattern for close to the second stitching line. A recommended . Some wide or one of the utility or patterns designed for knits will have ¼- stitches found on most inch seam allowances, eliminating the machines will also work to finish the need for trimming but also eliminating edges. For best results with the overlock any margin for adjusting size. Select a stitch, trim seam to ¼ if needed, and seam with enough stretch for the fabric. use the proper overlock foot for the machine to guide the raw edges along Sergers are great for sewing knits. A as the stitches are formed over the edge three- or four-thread serger stitch will of the fabric. Reducing the foot pressure give a quick, durable, professional finish slightly on soft loose knits will help to seams while maintaining stretch. prevent seams from stretching and Adjusting the differential feed on the being wavy. serger prevents seams from stretching too much and becoming wavy. Sergers and cover stitch machines allow you to duplicate techniques found in ready-to- wear, such as the flat lock or double- sided flat seam.

The conventional sewing machine is also quite capable of producing seams on knit fabric. Use a plain seam for stable and moderate-stretch knits. For lighter weight knits and some medium- Areas to Stabilize weight knits, use a double-stitched Seams that get a lot of stress and may seam using a , zigzag, or a stretch out of shape, such as shoulder, twin needle. Stitch on the seam line and 1 , and waistline, need to be /8 inch away. For greater elasticity in taped for stability. Narrow tape,

5 woven , woven seam tape, or have special stretch stitches. transparent elastic can be used. Stay- If the fabric has a lot of crosswise Tape™ is a lightweight nylon tape that stretch it may be necessary to make doesn’t add bulk and is washable and vertical buttonholes to get a smoother, dry cleanable. Sew the seam, catching neater looking buttonhole. the tape in the seam. On lightweight knit, press the seam allowance to one side and close to the seam line through all layers.

Use vertical buttonholes that run parallel to ribbing.

Ribbing Rib knit trim is designed to have great crosswise stretch and recover to its original size and shape after stretching. It is generally sold by the inch in tubular plackets should also be stabilized form. Rib knit is folded double with the by applying a strip of lightweight fusible folded edge used as the outer finished interfacing or hand stitching a piece of edge for band trims. Some ribbing seam tape within the seam allowance comes with finished outer edges and is area only. Stitch the zipper by beginning then applied single layer. Select a at the bottom of the zipper stop and ribbing similar in weight to the fabric. If stitch up one side. Start at the bottom pattern pieces are not provided, cut again and stitch up the other side. ribbing twice the desired width and long enough to fit around wrists, upper arms,

Stand on end to determine ribbing length.

Reinforce zipper with lightweight fusible interfacing. and ankles. Add ½ inch for seam allowances in both directions. To For buttonholes, the lengthwise grain of measure necklines and armholes, stand interfacing should follow the direction of measuring tape on end along pattern the buttonhole. A corded buttonhole will seam line to determine length also give more stability to buttonholes accurately. Cut ribbing two-thirds the on knit fabric. Some machines even

6 measured length of garment seams Hems lines plus ½ inch for seam allowances. Allow the garment to hang 24 hours V-necklines are cut the same before measuring the . Hems can measurement as the garment neckline be done by hand or machine, or they seam measures. Ribbing may be can be fused. For very heavy knits, applied flat or in-the-round. In the flat double stitch the hem. If topstitching a method leave one seam open before hem on textured knits, a zigzag stitch applying ribbing. For the in-the-round may look straighter than a straight stitch. method, seam ends together, trim seam A cover stitch is also good for hemming allowance if necessary to ¼-inch. In knit garments. If a cover stitch machine both methods, fold ribbing is half is not available, using a stretch double lengthwise and press crease, match or triple needle can duplicate the look of center and quarter marks to each other, the cover stitch. The two or three rows and stretch ribbing to fit as it is sewn in of topstitching on the right side and a place. row of zigzag stitching on the bottom side gives the necessary stretch Pressing required for knits. Choose a 2.5 mm or Knits do not require a lot of pressing 4 mm twin needle and textured nylon during construction, another reason that thread in the bobbin and lengthen the makes them quick to sew. When stitch length slightly. If the knit tends to pressing is needed, test on fabric scraps curl, interface the hem area with a for the correct amount of steam, heat, lightweight fusible tricot knit interfacing. and pressure. Remember to press and A machine can be used for not iron the fabric. To prevent the fabric an invisible hem on stable knits for a from being flattened too much, place the dressier look. fabric on a terry towel and use a press cloth.

Sewing Checklist Needle size Machine Marking Methods Seams Setting Single Knits 8/60–11/75 12 / 2mm Chalk, marking Plain, double sewn, twin needle pens, soap sliver Double Knits 8/60–14/90 10–12 / 2– Chalk, marking Plain, double sewn, welt, slot, piped 2.5mm pens, soap sliver, thread Interlock Knits 6/60–11/75 12/2mm Any type except wax Plain, double sewn, twin needle, stretch Raschel Knits 12/80–14/90 10–12 / 2– Pins, tailor tacks Plain, double sewn 2.5mm Sweatshirt Knits 10/70–14/90 9–12 / Chalk, marking Plain, zigzag, double sewn, twin 2.5–3mm pens, soap sliver needle, welt, serged, flatlock, piped Athletic 10/70–12/80 10–15 / Marking pens, tape Double sewn, serged, zigzag Knits 1.5– 2.5mm Tricot Knits 8/60–12/80 12 / 2mm Outward notches, chalk, Double sewn, twin needle soap sliver Sweater Knits 10/70–14/90 10–12 / 2– Pins, thread Double sewn, zigzag, serged 2.5mm Stretch 10/70–14/90 10–12 / 2– Chalk, marking Plain, double sewn, welt, piped terry/velour 2.5mm pens, soap sliver, pins Action Knits 10/70–14/90 10 / Chalk, marking Stretch, twin needle, serged 2.5mm pens, soap sliver, pins

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STRETCH GAUGE

Fabric with 20% stretch such as: jersey knit, double knit, and interlock knit

Stretch 4 inches of folded knit fabric from here to here

Fabric with 25% stretch such as: nylon tricot, interlock, and velour Stretch 4 inches of folded knit fabric from here to here

Fabric with 35% stretch such as: sweater knit, velour, and terry knit Stretch 4 inches of folded knit fabric from here to here

Fabric with 75% stretch such as: knit, fabric with spandex or Lycra® Stretch 4 inches of folded knit fabric from here to here

For more information on sewing knit fabrics, see Claire Shaffer’s Fabric Sewing Guide.

Original publication authored by Rose Marie Tondl, Extension Clothing Specialist , University of Nebraska. Revised and used with permission by Linda Heaton, Ph.D, Retired Extension Specialist for and Clothing, University of Kentucky.

Further revisions done by: Marjorie M. Baker, M.S. Extension Associate for Textiles and Clothing

March 2006

Educational programs of Kentucky Cooperative Extension serve all people regardless of race, color, age, sex, religion, disability, or national origin.

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