Bernina Artista 730E User Guide - Page 259

Prevention and Remedy of Failures Note the following advice to recognize the causes of most of the operation failures in the embroidery computer that might occur. Check First Whether: • upper and lower threads are threaded correctly • the needle is inserted correctly - flat part of the shank to the back • the needle is the correct size (see Needle/Thread Chart on pages 17-19) • the embroidery computer is clean - remove any thread lint • the hook race is clean • bits of thread are trapped between the tension disks and under the bobbin case spring Removing Trapped Thread If the lower thread breaks and the thread is trapped in the area of the take-up lever, proceed as follows: • power switch to «0» (off) • remove the screw on the head frame with the angular Torx key • pull head frame to the left • remove remnants of thread • attach head frame and tighten screw • Use only 130/705H needle system • Needle is bent or blunt • Needle is not correctly inserted • Push all the way to the top when inserting • low quality, badly polished needle used Needle Breaks • needle clamp screw is too loose • defective stitch plate Unsatisfactory Stitch Formation • remnants of thread between tension disks: • pull folded thin fabric (use the fold, not an outer edge) back and forth between the tension disks to clean the left and right side of the thread tension Trouble ShoToitteinl g1 Upper Thread Breaks Possible Faults: • upper thread tension is too tight • use of low quality needle. It is best to buy needles in a BERNINA store • needle has been inserted incorrectly. The flat part of the shank must be to the back • needle is blunt or bent • use of poor quality thread, thread with knots, thread too old or dried out Possible Solutions: • attach foam pad • use appropriate spool disc • use net for even unwinding of thread (pull over upper thread spool) • stitch plate hole or hook tip is damaged: take the embroidery computer to an authorized BERNINA dealer • reduce embroidery speed Lower Thread Breaks • lower thread tension is too tight • lower thread is trapped in the bobbin case: • Replace bobbin • needle is blunt or bent • the stitch plate hole has been damaged by the needle: • It must be polished by a BERNINA Technician • remove any remnants of thread from under the bobbin case spring • adjust thread tension • used wrong or no stabilizer at all • incorrectly threaded; check upper and lower thread • when embroidering, thread pigtail tensioner with lower thread • use appropriate spool disc • clean and oil hook (use original oiler only. See Cleaning and Lubricating on page 185) Embroidery Computer Fails to Run or Runs Slowly • plug not fully inserted • power switch in «0» (off) position • embroidery computer requires normal room tem- perature for operation Defective Sewing Light • take the embroidery computer to an authorized BERNINA dealer Lower Thread Indicator Sensor • bobbin cover is not closed • not activated in the Setup Program • remove any thread lint and remnants from the bobbin case Skipped Stitches • incorrect needle used Upper Thread Indicator Sensor • not activated in the Setup Program Embroidery Support - Messages 255