Interesting thought, Rita, about the kinds of threads that do well with Bottom Line versus Aurifil 50 wt (my two
go to bobbin threads). Recently, I kept getting a thread shredding problem with Sulky 40 weight... I had Bottom Line in the bobbin. Frankly, I thought the problem was upper thread tension or perhaps the needle (my mantra is always "TNT" (thread, needle, tension). I played with the tension, I changed the needle to three different types and still had shredding. WELL, after all THAT!

, I I changed the bobbin thread from Bottom Line to Aurifil 50 wt and it made a world of difference--no more shredding. I had also played with slowing down the machine speed, but to no effect. So, I wonder whether the Bottom Line was too strong a thread for Sulky which is rayon and it responded better to a cotton in the bobbin? Any thoughts out there?