Inconsistent Automatic Buttonhole Completion?My Singer Heavy Duty 4452 sewing machine is completing a seemingly random amount of each buttonhole I try to sew. Sometimes it does the full thing, sometimes only half, part of one side, all but the end, etc. When it stops making progress, it just keeps going back and fourth in place. The "push" lever is down and I push it back every time. Is there something I need to do for this specific problem, or is it something that more general solutions will fix? Thank you.
