Pfaff 90 Owner's Manual - Page 29

3. Needle Breaks Cause: Bent needle strikes point of sewing hook. Needle too thin or thread too heavy. Fabric pulls needle so it bends and strikes needle plate. Bobbin case inserted incorrectly. 4. Faulty Stitch Formalion Cause: Improper tension. Thread too heavy, knotty or hard. Bobbin unevenly wound. Pieces of thread between tension discs. 5. Machine Feeds lmpropery Cause: Machine does nat feed because stitch length control set on "0". Accumulations of lint pocked between feed teeth. Remedy: Replace needle at once to prevent further damage. Use correct needle and thread sizes. Don't force the feeding motion. Guide the material lightly. Push bobbin case until you hear it snap into place. Remedy: Adjust tensions as instructed. Use only first-rate thread - the correct size for the needle and fabric. Dont run thread over finger when winding the bobbin, but lead it around needle thread tension. Raise presser bar lifter and remove thread. Remedy: Regulate stitch length, as desired. Take off needle plate and remove lint with a stiff brush. 26