Thank you, Lee Ann for posting. I am having the exact same problem with my Bernina 640 e but I am not using any basting spray or adhesives. It seems to be having trouble getting through the places where many seams intersect and the material is several layers. This I think would cause the same problem you had with the gumming as the machine needle so maybe it causes the needle to be off just a hair sluggish and not pick up the bobbin thread? I would like to know what type and size needle you use?