I'm interested in whether or not you took the guide classes and followed what they said. I have had 2 Berninas (1630 and 180 which is my current Bernina) and you do have to do what they say and be diligent about cleaning the bobbin area and changing needles. I never had any problems with thread on mine but sometimes did have to make some tensions adjustments for specialty threads and have a spare bobbin case so that I can use one when I need to adjust the bobbin tension.