An improperly inserted bobbin will lead to weak, sloppy stitches. The Singer 534 Stylist is a lock-stitch household sewing machine that threads with a standard two-thread upper- and lower-threading system. You can either hand-wind the bobbin or use the bobbin winder on top of the sewing machine. If you hand-wind the bobbin, be careful to avoid pulling on the thread while you wind it or it can catch when you run the machine.
Slide open the plate over the bobbin casing. If the plate is hard to slide, add a drop of sewing machine oil in each track and slide the cover back and forth a few times to loosen it.
Remove the old bobbin and place a drop of sewing machine oil on the moving part at the base of the bobbin case. You can see which part moves by looking into the bobbin case while turning the hand wheel toward your body.
Hold the bobbin and gently pull the free end of the thread. The bobbin should be turning counterclockwise. If it is turning clockwise, flip it over so it turns counter-clockwise. Drop the bobbin straight down into the bobbin case when you have it turning the right direction.
Pull the thread through the notch closest to the bobbin, then slip it under the tendion leaf spring and tug it forward so it goes back into the slot.
Pull the thread end out about a hand-width, then place it across the bobbin at an angle. Hold onto the thread end as you close the slide plate, and slip the thread into the small oval groove near the center of the slide plate as the plate clicks shut.