Bodysuit Sewalong: Inserting the Zipper
Zippers in bodysuits are an interesting puzzle. You need one to get into your costume, but it can be tricky to combine the necessarily un-stretchy zipper with very stretchy fabric without puckers or waves. So let’s talk about a couple of my favorite tricks for neat, hassle-free zipper insertion on stretch fabrics!
Depending on which view of the pattern you pick, the M7217 bodysuit instructions show either a standard centered zipper or an invisible zipper, placed at center front or center back. You can use either method in either zipper location, depending on your preference. In this post I’m going to demonstrate a third option, the exposed zipper, which is applicable to a whole range of characters in comics and elsewhere.
First tip: interface your zipper location
Before inserting a zipper in stretch fabrics, I like to stabilize the seam allowances with a strip of fusible tricot interfacing. It’s lightweight and has some give to it, so it’s well suited to stretch fabrics, but it also makes the fabric a lot more stable and less likely to bubble. You don’t want to affect the stretch of the rest of the bodysuit, so make the strip about an inch wide and an inch longer than your zipper. Lay the bodysuit on the ironing board, making sure that nothing is stretched out of shape, with the back side of the fabric facing up. Fuse the interfacing strips to the seam allowances on either side of the zipper location, using a press cloth to protect your iron from excess goo.
Second tip: hand baste the zipper
Trust me, it’s worth the extra fifteen minutes. I like to work with the bodysuit totally flat on a table, so that the weight of the fabric can’t stretch it out. If using the standard zipper insertion method (views C and D), sew the lower portion of the seam and baste the zipper area closed before you begin. Pin the zipper at each end, and hand baste the zipper on each side as shown in the instructions.
For an invisible zipper, most methods have you insert the zipper before sewing the seam. That means you need to be careful that the top and bottom of the zipper are aligned with the exact same spot on each side. I like to baste the zipper to one side, line up the other side on top, and pin the top and bottom of the zipper in place before I baste. (If the fabric is very stretchy or lightweight, you may need to pin the full length and then baste.)
Third tip: finesse the needle position
Some zipper feet are adjustable, but many are fixed (though they may allow you to choose a right or left position.) I’m rarely satisfied with the default placement, so I use the needle position dial on my sewing machine to shift my sewing closer to the zipper teeth than the foot would otherwise allow. This really applies to any zipper insertion, but it’s especially useful when your zipper is on display at center front and you need it to look perfect.
You can actually sew invisible zippers this way, without an invisible zipper foot—just use your fingers to unroll the coil as you sew, and adjust your stitches to land a needle width or so away from the teeth. Don’t sew through the teeth, though, as that will prevent the zipper from closing.
Adjusting the needle position also makes it easier to close up the rest of the seam after you insert an invisible zipper. That first inch or so can be tricky, since the bulk of the zipper tape gets in the way and makes it hard to sew straight, but if you shift the needle all the way to one side it’ll help keep the tape out of the way of the foot. Just remember to mark your stitching line first, since you won’t be able to measure off the marks on the needle plate if you’ve adjusted your needle away from center.
Sewing an exposed zipper
To insert an exposed zipper in your bodysuit, first mark where you would like the zipper to end. Staystitch 3/4″ from the edge for at least a couple inches along the bottom of the zipper’s length, then across the bottom of the zipper to the edge of the fabric. You can staystitch the entire length if you want, but be careful not to stretch the edge while you sew as this will result in a ripply zipper.
Sew the center seam below the staystitching, starting exactly on the stitching line and backstitching so it doesn’t unravel. Clip into the corner. Open up the seam and press it flat, making sure that the staystitching rolls slightly to the inside. Fold the lower seam allowances down to square off the bottom of the zipper opening. Pin the seam allowances to hold them in place while you work.
Open up one seam allowance and baste the zipper in place, placing it face down on the right side of the fabric. Here I’ve aligned the edge of the zipper tape at 1/2″ from the fabric edge, and basted right on top of the staystitching to help guide my sewing. Sew the zipper to the seam allowance only – leave the outer layer alone for now. The stitching line is about 1/16″ inside the staystitching.
Flip the zipper to the inside and align the other edge. Baste and stitch, making sure that your stitching line is inside the staystitching so it won’t show. Once again, stop right at the base of the zipper and backstitch. Turn the zipper over and do the final topstitching from the outside.
I like to baste my zipper flat from the outside before topstitching, to control the roll of the fabric and make sure it looks nice and even. Otherwise, the stretchy fabric can shift as you sew and create wrinkles or puckers in the final result. Topstitch down the length of the zipper, across the base, and back up.
If you will be wearing the zipper open at all, you may want to trim the seam allowances back so that they’re hidden behind the zipper tape. You can do a second row of topstitching right outside the first to enclose the seam allowances and ensure the zipper lies completely flat.