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How to distinguish sewing machine needles

The needle of a household sewing machine is different from that of an industrial sewing machine. The needle handle of an industrial sewing machine needle is a circular cylinder, and a part of the needle handle of a household sewing machine needle is cut off from the circular cylinder for easy installation by beginners who do not know how to use the sewing machine

The standard for sewing machine needles is universal worldwide, with sizes 9, 11, 14, and 16. The smaller the model, the thinner the needle, and the larger the size, the thicker the needle. Needles 9 and 11 are suitable for thin fabrics such as chiffon, fine fabric, thin cotton, chiffon, and warp knitted fabrics. No.14 is suitable for medium fabrics (linen, cotton, herringbone, double-layer weaving, high-end dense woven chiffon). No.16 is suitable for making thick fabrics (denim, twill, herringbone, coated fabrics, woolen fabrics, canvas)

Needle testing method: Place the needle on a flat surface such as a needle plate or glass and roll it. The gap between the needle and the flat surface should be the same (bent needles cannot be used). Thin fabrics are made with fine threads and needles, and the pinholes are not too large; Thick materials require coarse needles to penetrate the fabric without damaging the machine needles. The needle hole of the machine needle is the part that carries the machine needle thread through the sewing material. The processing around the pinhole area must be very smooth and uniform, and the suture can freely pass through the pinhole. Only this type of needle will not break during use. One of the reasons for frequent wire breakage is caused by pinhole burrs. The inspection method is to thread the wire into the pinhole and let the needle slide freely up and down. If there are burrs, they will be clear at a glance. There are needle grooves on both sides of the pinhole. One is a long groove and the other is a short groove. When the needle passes through the fabric, it can ensure the free movement of the sewing thread. Otherwise, the sewing thread will be squeezed on the side of the needle by the sewing material. Needle material quality: Poor quality needles are very soft, and they are easily pulled out of place during sewing. The misalignment of the needles can cause them to directly touch the needle plate, resulting in needle breakage. The needle tip should be smooth and free of sharp and rusty spots, which reduces the risk of cutting fabric fibers by the needle



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