Hello! I am new to sewing swimwear and I wanted to use the twin needle for a cover stitch to give it a professional look. I mastered the serger, now I need to finish off the swimsuit with the twin needle. However with the Wooly Nylon thread I’ve found it extremely difficult to figure out the right settings (tension, presser foot tension, width, length…) I have tried several combinations of settings, and the closest I have gotten to clean lines the back is completely fluffy and messy. I don’t know where I’m going wrong! Pretty please if anyone has worked with wooly nylon and has setting recommendations so this doesn’t happen it would be greatly appreciated 🙂 I have the Singer Heavy Duty 4423 and using Wooly Nylon stretchy thread, and I used the machine’s winder for the bobbin and wooly nylon through the needles as well. Thanks!