A sewing machine is a precise machine in which all the pieces must work exactly as they were meant without even a minute adjustment. The needle, bobbin case and bobbin must all turn and feed at exactly the same time and in the same motion or the machine will not work properly. The bobbin case is the round part that holds the bobbin in the bottom arm of the machine. Cleaning the bobbin case and adjusting the hook fixes any bobbin case issues.
Things You'll Need
Turn the wheel on the right of the Pfaff sewing machine toward you until the needle reaches the highest possible position.
Remove the metal plate on the feed dog by pressing down on the raised ridge and pulling forward.
Remove the bobbin casing by pulling on the lever on the front of the case. Remove the bobbin.
Clean the bobbin case with the methylated cloth to remove lint or thread pieces.
Remove the shuttle hook by removing the screw with the screwdriver provided in the sewing machine tool kit. Clean the area under the hook and replace the hook by screwing the screw back into place. Make sure the hook is set perfectly centered, or the needle will hit it during sewing and break.
Clean the area inside the sewing machine where the bobbin case sits with the methylated cloth.
Replace the bobbin inside the bobbin case and replace the bobbin case in its proper place.
If the issues causing concern over the bobbin case persist after the cleaning and adjusting, adjust the shaft crank holding the bobbin case in place.
Unplug the sewing machine before working in the needle area to prevent any accidental injuries.