I would advise to change your needle - it is too large for Bottom Line. I use Bottom Line in the bobbin and King Tut on top. The quilt I'm working on has red thread (BL) in the bobbin and cream King Tut on top and everything works well. You use a 9-0/14 Top Stitch needle with King Tut. When using my embroidery unit for the quilting I also change the tension. So many things to keep track of!!