Subject: Basics of Sewing. Unit 1 Introduction to sewing machines. Quadrant 1 e-text

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1 Subject: Basics of Sewing Unit 1 Introduction to sewing machines Learning Objectives Quadrant 1 e-text The learning objectives of this unit are: Outline the need and development of sewing machines. Describe the hassles and problems faced by the inventors in the making of the machine. Describe the improvements made over time to make the machine better and to increase efficiency. Describe the functions of the various parts of the Single Needle Lockstitch. Describe the functions of the various parts of the 3 thread overlock machine. 1.1 Introduction The evolution of sewing machines was a gradual process, spanning several decades where technology kept improving over its earlier models, until it reached its present model. Here is a brief of this process. In 1755, the first possible patent connected to mechanical sewing was a 1755 British patent issued to German, Charles Weisenthal. He was issued a patent for a needle that was designed for a machine. However, the patent did not describe the rest of the machine if one existed. In 1790, the cabinet maker, Thomas Saint patented a machine with which an awl made a hole in leather and then allowed a needle to pass through. In 1807, the earliest reference to the use of a needle with an eye not being required to be passed completely through the fabric it was stitching, is found in a machine invented by Edward Walter Chapman, for which he and William Chapman were granted a British Patent in The machine was designed to construct belting or flat banding by stitching together several strands of rope that had been laid side by side. Two needles were required and used alternately. In 1810, Balthasar Krems, a German invented an automatic machine for sewing caps. Krems did not patent his invention and it never functioned well. In 1830, The first functional sewing machine was invented by the French tailor, Barthelemy Thimonnier, in 1830.

2 Thimonnier s machine used only one thread and a hooked needle that made the same chain stitch used with embroidery In 1833, Walter Hunt invented a sewing machine, a unique invention in the history of the world that used a lockstitch. The lockstitch used two threads, one passing through a loop in the other and then both interlocking. The first machine that is made of wood and uses a barbed needle which passes downward through the cloth to grab the thread and pull it up to form a loop to be locked by the next loop. Hunt later, lost interest in patenting because he believed his invention would cause unemployment. In 1846, Elias Howe patented the first ever proper lockstitch sewing machine in the world. Elias Howe's machine had a needle with an eye at the point. The needle was pushed through the cloth and created a loop on the other side; a shuttle on a track then slipped the second thread through the loop, creating what is called the lockstitch. On December 19, 1854, Wilson was issued patent for four-motion cloth feed. In this development, the flat-toothed surface in contact with the cloth moved forward carrying the cloth with it; then it dropped a little, so as not to touch the cloth; next it moved backward; then in the fourth motion it pushed up against the cloth and was ready to repeat the forward movements. This simple and effective feed method is still used today, with only minor modifications The first mechanical sewing machines were used in garment factory production lines. It was not until 1889, that a sewing machine for use in the home was designed and marketed. By 1905, the electrically-powered sewing machine was in wide use. 1.2 The Sewing Needle Now, let us learn about the various parts of a sewing needle. Butt

3 This is a small pyramid at the upper end of the shank. It is designed to make a single-point contact with the hole in the needle bar. Shank The upper end of the needle that is held in the needle bar the needle screw. The shank is usually round, but it can have one or two flat size. Designed to support and stabilize the needle blade, the diameter of the shank is usually larger than the diameter of the blade. Shoulder The beginning of the shank just above the needle blade. Scarf A small indentation above the eye that permits the hook or looperto pick up the thread loop. Needle groove A long channel on the blade. It is located on the side on which the needle thread enters the eye and provides a protective guide for the thread when the needle is rising and the needle-thread loop is enlarging. Eye An opening in the needle blade at the lower end of the long groove that carries the thread into the material to the hook or looperto make a stitch. Point Needle tip that penetrates fabric to pass thread to bobbin-hook and form stitch. Shape of point varies among needle types. 1.3 Types of Sewing Needles S. No Types of Sewing s Needle System 1. Single Needle Lock Stitch DA X 1or DB X 1 s 2. Single Needle Lock Stitch with Automatic DA X 1or DB X 1

4 Thread, Trimmer 3. Single Needle Lock Stitch witch Fabric Edge Trimmer Double Needle Lock Stitch Single Needle Lock Stitch Zigzag THREE Thread Over Lock FIVE thread Over Lock With Safety Stitch DA X 1or DB X 1 DP X 5 DB X 1 DC X 1 or DC X 27 DC X 1 or DC X Button Hole DP X Chain Stitch Button Stitch TQ X 1 or TV X Lock Stitch Button Stitch TQ X 1 or TV X Inter Lock/Flat Lock UY X 1 or GAS 12. Feed Of The Arm TV X 1 or TV X 7 For Denim 13. One & Two Needle Chain TV X 1 or TV X 7 Stitch 14. Blind Stitch LW X 6T 1.4 Needle Type and Relevance of Type of Material to be Stitched S.No Needle Size Type Of Material 1. #9 to #11 Light Weight Materials (Silk, Synthetic and Knitwear) 2. #14 to #16 Medium Weight Materials (Textiles and Natural Fabrics) 3. #18 to #20 Heavy weight materials (Denim) 4. #22 & onwards Extra Heavy weight materials (Leather)

5 1.5 Introduction to SNLS A sewing machine is a machine used to stitch fabric and other materials together with thread. Sewing machines were invented during the first Industrial Revolution to decrease the amount of manual sewing work performed in clothing companies. The sewing machines have greatly improved the efficiency and productivity of the clothing industry. Now, we shall discuss Single Needle Lockstitch Sewing, and Three Thread Overlock Sewing in detail, as these machines are the most widely used in the garment industry. A sewing machine is a machine used to stitch fabric and other materials together with thread. Sewing machines were invented during the first Industrial Revolution to decrease the amount of manual sewing work performed in clothing companies. The sewing machines have greatly improved the efficiency and productivity of the clothing industry. 1.6 Introduction to Thread Overlock An overlock is a kind of stitch that sews over the edge of one or two pieces of cloth for edging, hemming, or seaming. Usually an overlock sewing machine will cut the edges of the cloth as they are fed through, though some are made without cutters. The inclusion of automated cutters allows overlock machines to create finished seams easily and quickly. An overlock sewing machine differs from a lockstitch sewing machine in that it uses loopers fed by multiple thread cones rather than a bobbin. Loopers serve to create thread loops that pass from the needle thread to the edges of the fabric so that the edges of the fabric are contained within the seam. Overlock sewing machines usually run at high speeds, from 1000 to 9000 rpm, and most are used in industry for edging, hemming and seaming a variety of fabrics and products. Overlock stitches are extremely versatile, as they can be used for decoration, reinforcement, or construction. Overlock stitches are classified in a number of ways. The most basic classification is by the number of threads used in the stitch. Industrial overlock machines are generally made in 1, 2, 3, 4, or 5 thread formations. Each of these formations has unique uses and benefits:

6 1-thread: End-to-end seaming or butt-seaming of piece goods for textile finishing thread: Edging and seaming, especially on knits and wovens, finishing seam edges, stitching flatlockseams, stitching elastic and lace to lingerie, and hemming. This is the most common type of overlock stitch. 3-thread: Sewing pintucks, creating narrow rolled hems, finishing fabric edges, decorative edging, and seaming knit or woven fabrics. 4-thread: Decorative edging and finishing, seaming high-stress areas, mock safety stitches which create extra strength while retaining flexibility. 5-thread: In apparel manufacturing, safety stitches utilizing 2 needles create a very strong seam. For every 1 cm of seam length you would require 20 cm of thread to sew it. 1.7 Formation of Overlock Stitch When the needle enters the fabric, a loop is formed in the thread at the back of the needle. As the needle continues its downward motion into the fabric, the lower looper begins its movement from left to right. The tip of the lower looper passes behind the needle and through the loop of thread that has formed behind the needle. The lower looper continues along its path moving toward the right of the serger. As it moves, the lower thread is carried through the needle thread. While the lower looper is moving from left to right, the upper looper advances from right to left. The tip of the upper looper passes behind the lower looper and picks up the lower looper thread and needle thread. The lower looper now begins its move back into the far left position. As the upper looper continues to the left, it holds the lower looper thread and needle thread in place. The needle again begins its downward path passing behind the upper looper and securing the upper looper thread. This completes the overlock stitch formation and begins the stitch cycle all over again. 1.8 Conclusion

7 To summarize, this unit gave you an overview of improvements made to sewing machines as they were developed for use in the apparel manufacturing industry. You have also learnt about the various parts and functions of the SNLS machine and the 3- thread overlock machine.