Analysis on the Reason of Jumper of Sewing Machine

There are many reasons for sewing machine jumper, the main lock with the needle is not good
In the case of normal sewing, when you put down the sewing machine head, slowly turn the pulley, observe the needle rotation lock tip, line, ring with the three. Know the reason.
Adjustment method: 1, adjust the height of the needle bar 2, adjust the distance between the needle and turn the lock tip (not to touch the needle-based)
The main problem with sewing machine jumpers
First, the machine needle problem
(A) check the upper thread wear or wear a bit less than a bit. In this case,
(B) check the needle is installed correctly, such as needle-mounted slot installed anti-or skewed.
(C) check the needle type is applicable, needle bar height adjustment is accurate, and check the needle is close to the top of the needle bar. Needle installation is too high or too low, will affect the hook to take the line.
(D) check the needle is distorted. When stitching with a misaligned needle, the hook can not be snapped due to the formation of the loop away from the hook. Slight bending of the needle is difficult to identify directly with the naked eye, you can needle on the platform to turn, you can identify. In this case,
(E) check the needle movement with the hook is consistent with the time. The movement of the needle and hook fully cooperate with the time, the hook can accurately check the suture. In this case,
(6) Check the needle and sewing thread thickness is appropriate. Large sewing needles with fine sewing thread can also cause jumpers. This is because the needle of the large needle is longer and wider, and the hole of the pricked fabric is larger, so that the fine sewing thread has a larger space to move. If the hook is beyond the range of the hook,
(7) Check whether the machine needle needle eye due to melt-stuck chemical fiber sewing thread and blocked, so that the suture can not be normal delivery, can not form a coil. In this case,
Second, the pressure foot problem
Check if the presser foot is installed too high and the feed speed is too fast. The presser foot to install too high, will make the foot pressure to send the fabric of the lack of strength, this time with the presser foot fabric will shock, so that can not be pressed to form the upper thread coil; press foot to send cloth too fast, in the delivery fabric, The face line and the fabric with the fast away, the hook can not hook the upper thread.