I go against tradition when I serge bra seams. The “rules” are to either press the seams open and leave raw (if the fabric doesn’t fray), press the seams to one side and topstitch (again, if the fabric doesn’t fray), or to cover the seam allowances with a tape like 15 denier nylon bias-cut (scroll halfway down the page). Unless it’s a design detail like reverse hong kong binding, I don’t like raw raw edges on the inside or the outside of a garment. So, I wasn’t a fan of rule number one or two. Even on a straight seam, it can be difficult to sew an even length away from the seam. Can you imagine the difficultly of trying to attach tape neatly over a cross cup seam? Sure, with some practice and glue (to hold the tape in place), I’d get the hang of it over time. It’s the finish most commonly used in RTW. But if there’s an easier method, why not save myself the trouble? Enter the overlock stitch, or serge. Because of my cup size, an A or a B, I don’t stabilize the cups with a non stretch fabric like tricot. I usually lined cups with a classic or light weight power net or micro mesh. So an overlock stitch, which naturally stretches, makes it suitable as well as easy finish for my bras.
Normally, I use 100% polyester cone threads for serging. I choose it over 100% cotton because it has more give. I haven’t had a problem, but I’ve read that woolly nylon thread is a better choice for stretch fabrics. As the name suggests, woolly nylon is made from nylon fibers, which results in a thread that stretches and recovers, provides more coverage and has a softer touch. The increased coverage also makes it ideal for for rolled hems. It’s usually used in one or both loopers, but can be used in all four. Being more expensive than regular thread, I wondered if the extra money was worth it. Does woolly nylon thread really make a difference? Here’s what I found.
My standard serge for lingerie. The differential feed is set to normal, and the stitch length is set between 1 and 2. I reduce the stitch length to provide more coverage. I have found this to help prevent lace from “poking out” of the serge. All tensions are set to 4. I apologize that the serge is slightly messy. My Juki was acting up.
Wooly Nylon in Lower Looper:
Woolly nylon can be difficult to thread because it separate easily. It’s very similar to knitting yarns. To make threading easier, I tied off the woolly nylon with the polyester thread and pulled through. I had to adjust/loosen the tension of the lower looper to 3 in order to get a balanced stitch. The differential feed, stitch length, and other tensions stayed the same as in the 100% polyester. Do you also notice how the woolly nylon looks “fuzzy” compared to the 100% polyester?
Wooly nylon in Both Loopers:
Again, to avoid a threading fight with the Juki, I tied off the woolly nylon with the polyester thread and pulled through. Just like the lower looper, I had to adjust/loosen the tension to 3 in order to get a balanced stitch. The differential feed, stitch length, and other tensions stayed the same as in the 100% polyester.
Is it worth the extra money? Will I be using woolly nylon in the future? Totally, but not for the same reason as other sewers. Many claim that they use woolly nylon because of its hand; that it’s softer against the skin. IMOH, I wouldn’t notice a difference. I would use it for its coverage. I have a problem with the lace “poking out” of the overlock, which is why I reduce the stitch length when using polyester thead. With is increased coverage, woolly nylon encases the lace edges inside the serge, making for a clean finish. I love pretty seam allowances, don’t you?
Because wooly nylon is more expensive than your average thread, finding an inexpensive resource online with low shipping rates is your best bet. Buy in bulk to save on paying multiple shipping fees. This is assuming you don’t have a local vendor that stocks it.
YLI Wooly Nylon Thread via Amazon – $4.99
Fleishmans in Philadelphia – $5.90
Wawak – 1+ $4.10 / 4+ $3.99
Thread Art – $2.99 (not sure about quality)
Have you used woolly nylon thread? If so, then what was your experience? Do you have any tips?