When sewing with stretch thread, you need to use a needle that is specifically designed for this type of fabric. A ball-point needle will skip over the stitch, and a sharp needle will break the weave of the fabric. Ensure that you test the thread before sewing and use the appropriate needle. You should always check with the manufacturer's recommendations for needle size and type. It is best to test a few different needles and stitch settings to find which one works best for your sewing project.
If you use elastic thread, remember that you will have to manually wind the thread, and that it cannot be rewound on a bobbin winder. It is recommended to have at least 2" (5cm) of elastic thread on the outside of the garment before you begin sewing. You should use a long stitch for sewing with elastic thread, and avoid zig-zag stitching. When sewing with stretch thread, you should always remember to use the presser foot to guide your stitch. When using a sewing machine, be sure to avoid the automatic thread cutter, as it will cut the thread too close to the bobbin, which may allow the elastic to retract.
You can choose from the following types of thread. Nylon thread is a very strong, thin, and stretchable thread that does not lose its elasticity when you sew with it. Wooly nylon thread is a stretchy thread made of individual fibers and does not lose its stretch when under tension. Wooly nylon thread is often referred to as fuzzy nylon thread.
You can also use polyester thread for sewing knit fabric. The zigzag stitch is ideal for sewing knit fabrics because it will accommodate stretch. If you use the zigzag stitch, you can use a regular home sewing machine. The zigzag stitches also stretch slightly, which makes them excellent for all knit fabrics. A straight stitch will not work on knit fabrics. You can also use a regular sewing machine as a serger.
Wooly nylon is also a good choice for regular sewing machines. Just make sure that you wind it in the bobbin before sewing with it. Wooly nylon is a versatile sewing thread that works well with most knit and stretch fabrics. If you're making knit or swimwear, wooly nylon is recommended for best results. It will provide excellent stretch and elasticity, and reduce seam bulk.