Check whether the wire presser is too tight and check whether the wire feeder is too tight. There are several reasons for needle jumping in sewing machine: 1, the needle is not installed correctly, and the upper and lower grooves of the needle are along the line direction. 2. There are burrs in the hole of the threading plate. 3. There are burrs in the center of the pendulum bracket. 4. The distance between the center of the pendulum frame and the needle distance is too large, and its period cannot exceed1mm.5. The pendulum frame and the needle are out of synchronization, and the time difference is too large. 6.