I needed to find a way to make the decorative piping but also retain the stretch, as most piping is made with non-stretch woven fabric (cut on the bias) and a non-stretch filler cord for the roundness, whether you make it yourself or purchase. The solution? Round cord elastic and stretch pleather.

Make sure that the fabric you use has enough stretch to accommodate the stretch needed in the parts of the garment that it will be sewn to. I simply took the elastic and placed it in a strip of the fabric (stretch pleather in this case, as I liked the matte gold look) and sewed it close to the cord with a stretch stitch and zipper foot, much like you would when making regular piping. If you are using a different material, I would recommending overlocking the raw edge, as well. Then, I stitched this piping onto the garment, again with a stretch stitch, and it was ready to go!

You may find that with this type of trim, you need to either topstitch the trim after it is sewn on or create a facing for the edges, since some spandex fabrics have a tendency to want to roll the edges of the piping to the outside of the garment, which isn't an attractive look. Topstitching, a facing, or lining would solve this problem.

And there you go! A nice, cleanly finished edge that still allows for the material to stretch as need. Let me know if you found this helpful or have any questions!
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