Elastic thread is one of those timesaving little tools that's only timesaving if you know how to use it correctly! It's notorious for causing broken bobbins, skipped stitches, and worse, but used properly, it can create beautiful shirring, perfect gathers, and a comfortable, flexible fit in all kinds of garments.
What is elastic thread?
Just like it sounds, elastic thread is made from the same stretchy material as the elastic you use in wider strips—there's just less of it! This means that it behaves more like elastic than thread, and some sewing shops will even stock it with their elastic rather than with other types of thread. It doesn't come in as many colours as regular thread. In fact, you'll typically only find it in white, black, and maybe clear, depending on your shop. This won't greatly affect your work, however, as elastic thread is only used as the bottom thread in your sewing. Your top thread should still match your material.
What can I use it for?
Lots of things! Elastic thread is ideal for creating a shirred effect. Traditionally, shirring fabric involved row after row of tiny gathering stitches, which would take ages to do. Shirring with elastic is much easier and, in addition to the time and effort saved, it allows you to create flexible panels in your garments that provide a fitted look without being overly restrictive. It's perfect for waistbands and bodices, for kids' clothes (since it can grow with them), and for working with stretch fabrics, where it allows you to make the most of the material.
Tips and Tricks
Ready to give elastic thread a try? Here's what you need to know.
Use New Thread
Elastic that's stored over time tends to lose its stretch and become brittle. Especially if you're just starting out, it's important to use brand new elastic thread so you can perfect your technique. Once you've gained confidence, you'll be able to tell if any issues with your results are due to error, sewing machine settings, or thread that's gotten a bit too old.
Choose the Right Fabric
Lightweight materials are best for shirring. The thinner the fabric, the more tiny pleats can be packed into a small amount of space. Heavier fabrics don't pleat as well, and may cause the elastic to break. Very heavy materials, like leather or vinyl, won't work with elastic thread at all, while lightweight cottons can create densely pleated panels. Plan your projects carefully to get the best results.
For projects using stretch materials, you'll want to match the amount of stretch in the material to the stretch in your stitches by carefully adjusting your stitch length and tension. This will prevent a wavy seam without compromising the ability of the material to bend and flex.
The only way make sure your fabric and pattern are suitable for elastic thread is to test them. Start with a swatch of your chosen fabric and mark out measurements at regular intervals. Using the settings you plan to use for your finished project, stitch several rows of shirring. Measure the fabric to see how much it has shrunk, and give it a tug to see how far it will stretch. This will help you adjust your pattern, adding extra material where necessary so the finished shirring gives the garment shape without distorting it. You can also change the effect by altering your sewing machine's stitch length, or the type of material you're using. Every time you make an alteration, make sure to runs some tests before starting in on your final piece.
Adjust Your Patterns Accordingly
Once you've determined how much your shirring will gather your material, and how much stretch it imparts, you may need to alter your pattern by adding extra fabric. For example, if you're altering a girl's dress bodice to include a shirred band rather than lying flat, you may need to nearly double the amount of fabric in the bodice so that the shirring doesn't pinch. This process might take a bit of maths to work out, especially since each fabric will shirr differently. Careful measurements and test swatches are crucial to a good finished fit.
Handwinding is Key
Don't use your sewing machine or a bobbin winder for your elastic thread. As with invisible thread, winding bobbins with these tools can lead them to be overfilled, the thread stretched taut and packed too tight. In extreme cases, this can even cause bobbins to pop apart. Instead, wind your thread onto the bobbin by hand, keeping the thread just taut enough to wind neatly. This might take a bit of practise to perfect, especially since different sewing machines "prefer" different thread tensions in the bobbin.
Use Extra Bobbins
Since elastic thread is thicker than normal thread, and since it has to be wound relatively loosely, you can save yourself a lot of time and trouble by winding several bobbins in advance. This way, when you're halfway through a line of stitching, all you'll need to do is swap in a fresh bobbin rather than having to take the time to wind a new one.
Turn off Automatic Thread Cutters
As your sewing machine's tension pulls the elastic thread taut, it has a tendency to yank elastic thread free of the appropriate threading fasteners. If you leave only a short tail between seams, you'll find yourself needing to rethread the bobbin with annoying regularity. To avoid this, turn off your sewing machine's automatic thread cutter, if it uses one, and make sure to pull out a long tail of thread between seams.
Use a Walking Foot
As your fabric scrunches and wrinkles while you sew, the tendency as a sewist is to want to smooth and flatten it. After all, we spend so much of our time trying to achieve that perfect, crisp seam, it feels counterintuitive to let it rumple! You can avoid the issues caused by accidentally holding your material too taut by swapping out your regular presser foot for a walking foot. This can also help make your shirring denser, if you've not been able to achieve your desired results thus far.