Needles have been used for hand sewing since about 18000 BC and were originally made from ivory, bone, wood and horn. Their form has remained unchanged since then. During the fifteenth century iron needles were introduced for hand sewing, and in 1800 Balthasar krems of Germany was the first to use a needle with the eye near the point for a chain-stitch machine he had developed. The large scale production of sewing machines started about 1840 and this was paralleled by numerous developments in the manufacture and quality of machine needles. Today the steel needle in common use is a precision product which is critical to the formation of stitches.
The functions of the sewing machine needles are to form of a passage in the material through which the needle thread can wholly or partially pass and form a loop which can be picked up by the looper or hook mechanisms. Needles are made in straight or curved forms and their main construction features are –
Butt – The truncated conical shape at the top of the needle which facilitates its insertion into the needle bar or clamp.
Shank – Usually larger in diameter than the rest of the needle, the shank can be cylindrical in shape or flat on one side, developing on the method used to secure the needle in or on the needle bar.
Shoulder – The selection joining the shank to the blade.
Blade – The longest section of the needle, this runs from the shoulder to the eye.
Grooves – On one side of the needle there is a long groove which protects the needle thread as it enters and is withdrawn from the fabric. There is a short groove on the opposite side which extends a short distance above and below the eye and its purpose is to aid the passage of the thread into the material and loop formation.
Eye – An elliptical hole between the two grooves; the shape and finish of the inside top of the eye are important factors in the prevention of thread damage during sewing.
Point – This is shaped to provide the best penetration of the material being sewn.
Tip – The tip, when combined with the point, determines the ease and extent of penetration into the fabric.
Points and tips have a decisive bearing on the performance of the needle and the various types of combinations can be divided into two groups –
Round Points – These are used for the sewing of textile materials and whilst they all have a circular cross section, they differ in their tip shapes. In general, set point needles are used for most woven fabrics and the ball point needle is preferred for delicate and knitted materials. Both these points are available with light, medium or heavy tips and these combinations allow for good compatibility between the fabric and the needle.
Cutting points – These needles actually cut a hole through the material and because of this are mainly used for the sewing of leather, artificial leather and plastic materials. The points come in a variety of shapes. They all influence the set of the stitches and as a result the appearance of a row of stitches. The individual stitches are slightly slanted instead of being in a straight line.
Textile Notes24 