Machines sure seem to act like a toddler, no reason for doing something they just do it. My old Juki froze up, wouldn't move at all, the handwheel stuck solid. I put it away for a long time. I had a new one to use. I got it out and low and behold it sewed just fine. I absolutely did nothing to it, same thread, bobbin, settings, and needle as when it froze up. I gave it to a friend, and she is still sewing with it.