I found with both my Babylock and my Pfaff that it pays to use the bobbin made for that machine. I couldn't figure out what was wrong when there were so many nests on the bottom of the embroidery. Turns out it was the bobbin. Also matters how the bobbin is wound. The pfaff bobbin can be wound on the "bobbin winder" gadget but I finally figured out after many errors that those Pfaff bobbins that were wound on the "Bobbin Winder" were the ones causing all the problems. then i read in the small print on the box that it doesn't work with Pfaff. So although the bobbin fit on the gadget to wind it, it didn't sew well. After so many problems I learned my lesson. if you are using pre wound bobbins that's another problem to figure out...some work with some machines and some with others. with the Pfaff, it works better to take the cardboard sides off. the plastic ones don't work well with Pfaff at all. They may be ok with Babylock.