Despite what we have all been told, sometimes you can use invisible thread in your bobbin. I took a class with Helen Weinman from Heartbeat Quilts in Hyannis, MA many years ago and she told us that she has used invisible thread in the bobbin. Of course, you would have to thread a bobbin with some of the invisible thread and see if you machine likes it or not, if you don't try, you won't know. I really hope this helps. I have a Jonome 4000 and it has worked fine for me.