Singer 14T967DC Quantumlock Instruction Manual 26 - Page 66

How to Replace the Moveable Upper Knife Danger: Before replacing the moveable upper knife, disconnect power line plug from the wall receptacle. The moveable upper knife should be changed when it becomes dull. The moveable upper knife can be replaced according to the directions provided, however if there are any difficulties experienced, consult your Singer representative to make the replacement. Be sure that the power line plug is disconnected from the electric source. Open the looper cover and set the moveable upper knife (a) in the working position. Loosen the moveable upper knife set screw (b) and remove the moveable upper knife (a). Turn the hand wheel to lower the moveable upper knife holder to its lowest position. In this position, put a new moveable upper knife in the groove of the moveable upper knife holder, making sure that the edge of the moveable upper knife is approximately 0.5 to 1.0 mm below the surface of the fixed cutting blade (d). Tighten moveable upper knife set screw (b). a b d 0.5~1mm c b 65