Sometimes, when sewing, it is necessary to stabilize the seam to avoid it gets stretched. If we don’t do this, the finished measurements of the garment might vary.
Stabilizing seams is required either for wovens or knits.
The areas that must be stabilized are those where the cut is on the bias of the fabric.
Two methods can be used when stabilizing a seam:
- making a stitching along the seam allowance
- adding a stay tape (or silicone or knitted fabrics with a lot of elasticity).
You can apply the best-suited method for your garment, depending on the type of fabric used and the cost of the garment.
Seams
As mentioned before, we need to stabilize the areas that are cut on the bias. The seams are usually curves or diagonals such as necklines and armholes.
Usually, you don’t need to stabilize the entire seem. So you can work on those areas that require it.
Stabilizing by a Stitching (Stay Stitch)
The “stay stitch” consists of a topstitch parallel to the seam allowance, placed 3mm from the edge. This stitch is the first step before starting sewing the garment.
Use a short stitch length (between 2 and 2.5 stitches per centimeter) with a tone to tone thread, since the stitch will remain on the garment once it’s finished.
Keep in mind that the bias cut could change the shape of the seam easily, so it must be stabilized immediately after cutting the pieces (before ironing or embroidering).
Make sure the stitching is always in the same direction, from top to bottom.
Stabilizing by an Interfacing Tape with Chain Stitching
Stabilizing tape is a thermo-adhesive tape cut at the bias. Its width goes from 8 to 13mm, and ti has either a chain stitching or a cord right in the middle. The one with a chain stitching suits better on lightweight fabrics, and the one with a corded tape works better on heavyweight fabrics.
Since it’s thermo-adhesive, it’s secured to the fabric by ironing. When heating the tape, the iron must not slide to avoid distortions of the shape.
Place the tape between the seam allowance and the edge.
Silicone Stabilizer Tape
The silicone stabilizer tape is a very elastic and transparent polyurethane tape of 9mm in width.
The tape is attached to the fabric by a stitch.
Bias Stay Tape
The bias stay tape is a 100% cotton tape made of a very light fabric. It’s mostly used on lightweight fabrics. You’ll find tape in different widths.
Depending on the factory and the cost of the garment, one method or another will be applied. Or non-method might be applied. As a product developer, it is good that you know them and require them to improve your samples.
Olga Fuenmayor
Editor at Seampedia.
Fashion Technical Management / Consulting
Model development / Quality control / Production control.
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I am sewing a garment made with an eyelet fabric that has some stretch (not 100% woven cotton). The machine thread is either breaking or developing nests of thread, or the stitches are uneven in length. I tried rethreading the machine and the bobbin but still experience the same problem. Interestingly, when I sew on a woven fabric, there is absolutely no problem with the stitches. This makes me think that the machine foot is having difficulty running across the eyelet holes and that the timing is off as a result. I’ve searched the Internet, and I’m leaning toward using a tape placed over and under the seam line. Have you ever seen this problem? Can you recommend a solution? Thank you.
Hi Carol, definitely the problem is sewing across the eyelets.
You can try that trick that you mention (placing a tape over and under), or you can use the “Hump Jumper Foot”: a plastic foot accessory that looks like the letter “L.” It has a slot for the needle in the center and a choice of two thicknesses to level the foot. It usually comes with your sewing machine.
We hope it helps!
Kind regards.