Sewing precautions for fabrics

Sewing precautions for fabrics

1. The denim of denim is sewn with thick thread, which makes it difficult to form a thread loop, and makes the thick thread unable to escape from the loop of the rotary hook, resulting in thread breakage, thread rolling and stitch skipping. In addition to repairing with the above-mentioned thick material type method, there is a difference in this. Because thick wire is mainly used, the positioning hook of the rotary hook should also be processed and ground during maintenance, so that the thick wire can come out of the positioning hook easily. . And choose a hook that is not too worn.

In addition, Wuxi also provides solutions for the processing of jeans, which can help you understand how the step-by-step process of jeans is made, and the stitches produced by what machine are different. This solution can solve your problems in all aspects. of worries.

2. Down fabric Down fabric is sewed with vacuum cotton and down to form an extra-thick layer of 0.7-1.1cm. In this state, the machine needle and suture are not easy to form a good loop, which leads to skipped stitches. According to the situation of this extra-thick layer, first solve the feeding problem and replace the feeding dog with a thick material feeding dog.

The needle hole of the needle plate should be larger, and the feeding cam should be adjusted accordingly. Adjustment standard: the teeth are everywhere, and the needle tip of the needle should be in the needle hole of the needle plate: the height of the needle bar should also be greatly adjusted, and the height of the needle bar should be At the bottom dead center of the needle bar, the third thread on the needle bar scale should be lowered by 0.1cm. In this way, the principle of increasing the stroke of the needle bar is used to complete the hooking: the needle and hooking time also change, the needle bar Adjust the angle when it rises from the bottom dead center to the root line of the scale, and the angle adjustment value is the same as the above; increase the pressure of the presser foot: due to the extra thick material, the needle is prone to friction and heat, which may also make it difficult to form a loop. If necessary It needs to be solved by adding silicone oil at the line crossing.

3. When leather is sewn into leather, the fabric is astringent and causes poor feeding, resulting in skipped stitches. It can be repaired according to the method of the above-mentioned extra-thick material, but there are differences in solving the feeding problem. The nylon presser foot can be used to deal with the poor feeding, or the leather sewing can be treated with silicone oil.



4. Real silk before sand washing Real silk fabrics are very astringent and hard in the sewing process before sand washing, so that the machine needle and suture cannot produce good loops in the sewing material, and the formation of Jump stitches. Check whether the needle bar is worn or not. Check whether the hook tip is good and standard, because the hook tip is the key part of hooking the thread. There must be no burrs, bald tips and other faults. If found, you should use a diamond file or oil stone gold in time. Check the height of the needle bar, the standard of the needle bar height is: when the needle bar is at the bottom dead center, the needle bar scale line should be on the second line. In this way, when the needle bar rises to the root thread, it is good to adjust the angle between the needle and the tip of the hook.

Attention should be paid to adjusting the angle first: if the needle bar has a slight gap, push the needle bar slightly to the left with your left hand, and then adjust it. The standard for adjusting the angle between the needle and the hook is: when the needle bar rises from the bottom dead center to the scale line, the tip of the hook should be 1.1-1.5cm above the needle hole, and the lateral clearance between the tip of the hook and the needle is O. 02-0.05cm; the feeding mechanism is also the key. First, check whether the feeding cam is standard, because the teeth should be lower when sewing thin materials, and the feeding cam should be adjusted appropriately.

5. The real silk after sand washing The real silk fabric after sand washing is soft, so it is difficult to form loops when the machine needle and the stitching thread pass through the sewing material, but for the height of the fabric and the bottom edge, it will even lead to high and low places. There is a gap under the presser foot, and the loop cannot be formed normally, resulting in skipping stitches.

At this time, check whether there is a gap in the needle bar; check whether there is a thorn or bald tip on the tip of the hook: check the height of the needle bar. Because it is a high and low layer, it can be classified as a medium-thick material type. When repairing, think calmly and then proceed to make appropriate adjustments to the height of the needle bar. According to this type of situation, the height of the needle bar should be adjusted based on the third line of the scale from the needle bar to the bottom dead center. The specific adjustment method is: The adjustment angle should be adjusted according to the standard when the third line of the scale rises to the root line: Check whether the needle hole of the needle plate is standard: If the presser foot uses the presser foot of a medium-speed lockstitch machine, the back of the presser foot should be ground away to form When feeding the cloth, the presser foot and the upper and lower layers of the sewing material smoothly come down to press the sewing material.