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By: Chidambaram Rameshkumar and Dr. N. Anbumani
Bannari Amman Institute of Technology, Sathyamangalam
PSG College of Technology, Coimbatore
crktex@gmail.com 1.0 Introduction
Every creature on this earth wants to look beautiful including the human being. Since the development of various civilizations, considerable effort has been given for achieving this. Use of garment is one way to fulfill the long cherished need of human being. Various techniques of garment making were tried in the past but nothing has been successful as sewing. The sewing thread is one of the most important elements to produce neat firm and desirable seam, which gives garment necessary aesthetics and helps to make the quality product. High-speed sewing machines can stitch at the rate of 6000 stitches per minute. This sewing thread is subjected to heavy stresses and strain at the various points during the processes.
The needle is accelerated to over 180 kilometers per hour in the forwarded direction brought to rest and accelerated again backward before returning to the rest. The whole cycle is repeated approximately 120times per seconds. With lock stitches each length of thread is passed through the needle up to 40 times before being set in to the fabric. Sewing machine needle may reach a temperature up to 360 a C due to the frictional forces that are developed between the needle with thread and needle with fabric. This depends on the thickness of the fabric, number of piles and speed of the stitching.
2.0 Ideal sewing thread
The ideal sewing thread should confirm to a high standard of single thread strength and perfectly balanced twist. It should not have yarn defects like knots, cuts, snarling, twist subs etc. Thread should have color fastness and wash fastness. Length of the sewing thread should be within the specification. It should be smooth free from protruding fibres with exceptional good appearance .This same thread should perform plain stitch, button stitch, and button holding at various speeds.
3.0 Fibres for Sewing Threads
3.1 Glass and Asbestos
These are so unsatisfactory and only used when essential to provide complete homogenous sewn product.
3.2 Viscose Rayon
The low wet strength and poor abrasion resistance are main limitations as sewing thread.
3.3 Polyethylene and Polypropylene
Low melting point, inherent stiffness with tendency to slip in the seam, Poor fatigue resistance, poor creep and light fastness are the major limitations.
3.4 Linen and silk
Because of its low demand it has a limited usage.
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