WHAT IS IT?
A centered zipper is a type of zipper insertion in which the zipper teeth are centered between the fabric opening. In this type of zipper application, the fabric covers the zipper equally on both sides, meeting in the middle of the opening, and the stitching is visible on either side of the zipper opening. The zipper teeth may be visible as you move and the fabric layers pull apart, but when the garment is flat, the folded edges meet to completely cover the zipper. To insert a centered zipper, you’ll need a regular zipper, not an invisible zipper. (Can’t tell the difference? If you can see the zipper teeth or coil as a ridge on the right side, it’s a regular zipper. If the tape is flat and the ridge of the zipper coil is on the underside, it’s an invisible zipper.)
Centered zipper on Crescent Skirt
WHEN DO YOU USE IT?
This is a fairly simple zipper insertion method, so it can be used on several different types of garments, including skirts, dresses and blouses. It’s most often used at center back and center front openings, and it can also be used at the side seams. I find that regular zippers (page link) are stronger than invisible zippers, so I recommend them for snug-fitting garments.
HOW TO SEW A CENTERED ZIPPER
Sew the seam below the zipper. If the zipper is going into an unlined garment, finish the seam allowances of the zipper opening all the way down to the bottom of the seam. If the zipper is going in a lined garment, where the seam allowances will be enclosed, leave the seam allowances unfinished. Machine baste (page link) the zipper opening above the seam closed, and press the seam allowance open.
Switch to a zipper foot. From the inside of your garment, with the top of the zipper opening facing you, open up the right seam allowance. Place the closed zipper face down on the seam allowance with the bottom stop at the top of the seam and the coil/teeth centered on top of the seam. Pin along one side of the seam allowance. Open the zipper and machine baste the zipper to the seam allowance only, down the middle of the tape. When you get close to the bottom, zip up the zipper a little so you can baste all the way to the bottom of the tape.
Zip up the zipper, and baste the other side of the zipper to the opposite seam allowance. A good way to ensure the zipper stays centered is to aim for the same amount of seam allowance showing on both sides of the zipper.
Flip the garment over to the right side. Hand baste (page link) on either side of the seam, across the bottom just below the end of the zipper, and up the other side, ¼” (6mm) away from the seam. Make your basting stitches even, as you’ll use them as a guide for topstitching in the next step. You can skip the hand basting and go straight to topstitching the zipper if you feel confident, but basting will keep everything in place so your topstitching is more accurate.
Starting at the bottom of the placket (page link), topstitch (page link) just outside of the basting line across half of the bottom edge, then pivot and sew up the side to the top. Start again at the bottom and sew up the other side of the zipper. Press the zipper opening, and remove the basting stitches.
Tips + Notes
- If you prefer, you can topstitch starting at the top, across the bottom, and back up the other side in one motion. Starting from the bottom both times is good for fabrics that may ripple or shift.
- For zippers in lightweight or shifty fabric, you may want to stabilize the zipper opening with fusible interfacing (page link). Cut two 1″-wide (2.5cm) strips of interfacing the length of the zipper opening, and fuse along the zipper opening.
Source : The Sewtionary An A to Z Guide to 101 Sewing Techniques + Definitions
About the Author : Tasia ST. Germaine