Professional Finishes for Sweater KnitsGreat-looking edges and closures are the key
Gorgeous knit garments are the sum of many parts: unique fabrics, flattering silhouettes, and beautiful finishes for sweater knits. With information on stitching seams, hems, and facings in Threads No. 146, I got you started on sewing your own sweaters. Here, I’ll show you how to take your knitwear to the next level. You’ll learn additional ways to finish the edges so they look—and stretch—just right and discover tips on putting in long-lasting buttonholes and zippers that cooperate with the characteristics of your sweater knit. With these skills at your fingertips, you’re on your way to developing a wardrobe of chic sweaters for every occasion.
Frame the edges with ribbing
Ribbed trims provide stretch and stability. Good-quality ribbing is often hard to find, so consider substituting self-fabric (even the wrong side if it’s attractive) or other stretch fabrics as long as they have enough crosswise stretch and recovery. Cut the trim twice the desired finished width plus two seam allowances.
Determine the ribbing length
Cut the ribbed trim shorter than the circumference of the opening but long enough for the trim to stretch as the sweater is pulled over the head or body. The example here shows how to apply ribbing to a neckline.
Measure the neck circumference along the seamline of the paper pattern. If the ribbing has a lot of stretches, cut two-thirds of the neckline circumference plus two seam allowances. If you use self-fabric or other trim with minimal stretch, cut it three-quarters the neckline circumference plus two seam allowances. Then pin or baste the trim strip into a ring, and try it on to confirm that it fits over your head.
Sew a perfect circle
For ribbing to look truly professional and smooth, it must be evenly distributed on the garment edge.
With right sides together, join the short ends of the ribbing strip to form a ring. Finger-press the seam allowances open, and then fold the ring, wrong sides together, aligning the cut edges. Machine-baste the cut edges together, stretching the ribbing as you sew. The basting stitches will look loose or loopy, but they won’t show in the final garment. Starting at the seam, divide the ribbing into quarters, and mark the sections with a fabric marker or pins. Divide and mark the neckline into quarters by matching the center front and center back, and finding the halfway points between them.
With right sides together and raw edges aligned, pin the ribbing to the neckline, matching quarter marks; place the trim seam at center back, and sew. Fold the ribbing up.
Miter corners on V-necks
V-shaped and square necklines are treated much the same as circular ones: The corners are mitered after the ribbing is sewn to the garment. The directions here are for a V-neck, but the same process applies to necklines that have more than one angle.
First, chalk-mark the miter on the neckline with a vertical 2-inch line that divides the “V.” Attach the ribbing as described above for a circular neckline. Next, at the point of the “V,” fold the sweater front right sides together along the center-front line, and mark a line on the ribbing that is continuous with the original chalk-mark. Machine-baste the ribbing along this line, forming what looks like a little dart with a point just at the point of the “V.” Examine the angle of the miter, and adjust if needed. When you’re satisfied with the miter, sew it with a straight stitch.
Bind the edges for stability and style
Enclose the edges in binding for a clean finish. Binding-material options include self-fabric or lightweight jersey cut on the cross-grain (patterned knits can look great this way). You can also use Ultrasuede Light, but note that it doesn’t stretch much. Single-layer binding is lightweight; double-layer binding (sometimes called “French binding”) has two finished edges. Trim the seam allowances off the edge before binding them.
Prepare the binding
A single binding has one exposed raw edge; use this when that edge won’t show. It’s also good on fabrics that don’t ravel. Cut a strip of knit binding twice the desired finished width plus 1 inch for seam allowances and overlap and 2 inches longer than the edge you are binding.
Double-layer binding encloses all raw edges, so it’s a good choice when both faces of the fabric shown in the finished garment, such as on a cardigan front. Choose a lightweight knit for this binding; cut a strip six to seven times the desired finished width to allow for loss of width due to stretching, and 2 inches longer than the edge you are binding. Fold the binding strip in half lengthwise, with wrong sides together. Baste the layers together very close to the raw edges, stretching the fabric as you go.
Sew the binding in two steps
1. If you’re working on a circular edge, such as a round, closed neckline, leave one garment seam open to create a flat edge. With right sides together and raw edges aligned, position the binding along the garment edge. Stretch the binding slightly, and pin it in place. Sew with a 1⁄2-inch seam allowance. Press the binding and seam allowance toward the neckline. Cutaway excess length, and then close the open seam, joining the binding ends as well.
2. Fold the binding over the raw edges, and pin the free edge in the well of the seam. Turn the work right-side-up, and stitch in the ditch to anchor the binding. For a single binding, trim away excess binding close to the stitching.
Support buttonholes and zippers
Experiment for flat, attractive buttonholes
The tips below will help you sew buttonholes that resist stretching and distortion.
- Sew a test buttonhole. Evaluate it for appearance, stability, and ease of stitching.
- Add stabilizer. On a faced and interfaced edge, you might need no more than an extra patch of fusible interfacing on the wrong side of the buttonhole position.
- Improve fabric feed. Thick or textured knits sometimes catch or bunch up under the presser foot during stitching. To keep things moving smoothly, lengthen the stitch, and apply a temporary stabilizer (I like Solvy’s water-soluble version) to the bottom and/or top.
- Cord the buttonhole. For buttonholes on ribbing or self-trim, apply buttonhole twist or elastic thread as cording. Buttonhole twist provides complete stability and strength, but elastic thread enables the buttonhole to stretch. Test both to see which works better on your knit fabric. When the buttonhole stitching is complete, tie the cording ends together and bury them in the fabric near the stitch line. Then cut away the excess on the wrong side.
Stabilize for smooth, decorative zippers
To ensure a perfect zipper insertion, start with a zipper that’s compatible with your sweater knit’s weight or bulkiness. Make sure the teeth and the tape are flexible enough to work with your garment.
1. Stabilize the garment edge on the wrong side. To each side of the zipper opening, apply a 1-inch-wide, cross-grain strip of French Fuse or Fusi-Knit.
2. Baste to test. Place each half of the zipper tape along a front edge, right sides together. Machine-baste the zipper in place, and try on the garment. Check it see if it bows or hikes up at the front edge. If it ripples or bows, the sweater edge has stretched; reapply the zipper, easing the edge as needed. If it hikes up, resew the zipper, stretching the edge slightly.
3. Neaten the edges. Finish the inside by either serging or binding the zipper tape and raw edge together.
4. Topstitch. Turn the zipper tapes to the inside of the garment, and topstitch to secure them. If your knit is heavily textured or thick, you may prefer to omit the topstitching.