Sounds like I'm not the only one having problems using different threads on my Featherweight. I tried using Aurifil but the tension seems very tight- or maybe it's because of how hard it is to wind a bobbin without the spool jumping off, my bobbin is probably unevenly wound. I think Gutterman and Coats cotton work better for me, does anyone know if it's an issue with how the thread is wound on the spool? my other machines seem less particular.