The stitching position of the shuttle is closely related to the sewing performance.
When the shuttle line hook and the delay time position exceeds the limit, break is increased. In use, we can feel out of cotton and synthetic fiber, cotton can be used without disconnection in a wide range, but when the rotating hook line position when the time delay is too long, thread break rate will increase. The shuttle line hook right time position is generally between 2.0mm~2.6mm.
2.Tension and tightness of stitches
When the shuttle hook line time is delayed, the tension of the stitch gradually becomes slack. Compared with cotton yarn, the tensile strength of the synthetic fiber line is better, because it is easy to return to normal condition after stretching. The tension of the stitch is that the surface line is tightened and the reverse side of the sewing material appears on the surface line.
When the tension of the face line is smaller, the phenomenon of floating line will appear, the stitch like stitch on the back of the seam. As the tightening of the same line, cotton line is more prone to float line than the synthetic fiber line. With the delay of the shuttle position, the floating line loop phenomenon will decrease.
Bouncing pilotage has a close relationship with wire loop shape and needle tip position and the shuttle. The shape of a wire ring varies with the nature of the stitches, the shape of the needle and the amount of lifting of the needle.Cotton and synthetic fiber line line ring is different. The formation of cotton line ring is stable; and the synthetic fiber line formed by the line ring is very irregular, such as:the line ring down to elongated needle and backward muster will produce line distortion.
The relationship between hook time of a shuttle and skipping just is the relationship between the needle position and the number of skipping. The relationship curve is obtained in this experiment is easy to occur. For the position of the shuttle, when it is set to 2.5mm,the phenomenon of skipping will rarely occuron. For the needle plate,it will be most ideal when the position is adjusted in the upper needle shuttle tip about 1.2mm. Especially when using synthetic fiber lines, in order to prevent skipping, the best position of needle is needle tip close to the shuttle.