Originally Posted by
Onebyone
I don't know about this model of Bernina but have you tried a prewound bobbin? They are wound tight and full according to bobbin size. My older Bernina stitches better with pre wound bobbins.
Berninas can’’t use pre-wound bobbins. The bobbins are just enough different to prohibit it. The possible exception are the quilting machines. I think at least one of them uses standard M bobbins.