Needles of High Precision
We like to give you information on needle features, sewing technology, stitch formation, garment fabrication and solutions to basic needle problems.
The needle is one of the most important parts of a sewing machine. Without it, sewing would not be possible. Its task is to penetrate the materials that are to be joined in order to form a stitch hole. In the process, the needle guides the sewing thread through the materials and supports it during loop formation. Between the needle and the looper/hook or between the needle and the bobbin thread, a stitch is formed. Since industrial sewing machines allow to perform up to 10,000 stitches per minute, sewing machine needles have to be produced with highest precision.
There is a large variety of needle types and versions, suitable for different machines and used for all sorts of applications and stitch types.
|When looking at a needle, the viewing direction is always from the shank towards the point, the long groove facing downwards. This way we can define the directions “bottom”, “top”, “right”, and “left”. When angles are indicated, the long groove is set to 0° for reference. Degree values increase counterclockwise, i.e. “right” is at 90°, “top” at 180°, etc. Each needle can be divided into two sections: the clamping part consisting of shank and cone and the working part consisting of blade and point.|
|Style typesBasically, there are two different kinds of sewing machine needles:|
|1. Straight needles for chain stitch and lockstitch|
|2. Curved needles for blind stitch and overlock|
|Additionally, the needles are distinguished by the number of long grooves: lockstitch needles have only one groove, chain stitch needles have usually two.|
|needle having one groove needle having two grooves|
|Definitions Shank: The shank extends from the butt to the cone. Most needle systems have the same shank diameter for all sizes. Only for some needle systems, the shank diameter gradually changes depending on the needle size. In the sewing machine, the shank enters into the needle bar (hole or clamp) where it is usually fixed by a screw. The needle size and the producer’s logo are stamped into the shank. The diameter, length, and possible special shapes are determined by the sewing machine. There are the following shank types: Round Flat Flattened at the butt Grooved Notched Threaded Reduced The two most important types are the round shank and the flat shank, the round shank being the most common one. Cone: The cone is the transition from shank to blade. The length of the cone depends on the ratio shank diameter to blade diameter as well as on the angle or radius of the cone. Blade: The blade is the part of the needle between the end of the cone and the beginning of the eye. Also here exist different types, depending on the manufacturing procedure. Long groove: The long groove runs from the end of the shank to the beginning of the eye. It always faces the threading direction and, in most cases, is of the same width as the eye. When the needle penetrates the material or when the loop is enlarged by the looper/hook, the long groove protects the thread from severe frictional contact with the material.|
Short groove: The short groove is opposite the long groove, facing the looper/hook. It also protects the thread from severe frictional contact with the material.
Scarf: The scarf is a recess in the needle blade, which permits the unobstructed movement of the looper/hook and a reliable catching of the loop. The depth of the scarf is the distance between the blade diameter and the lowest point of the scarf. Eye: The eye is the opening in the needle blade through which the thread is inserted. Since the thread passes through the needle eye 40-70 times during the sewing of a lockstitch seam, the beginning and end as well as the surface of the eye must be well rounded and polished. Point: The point extends from the beginning of the eye to the end of the needle. Its position can either be centric or eccentric.