THREADS Factors Affecting Characteristic Of Thread • FIBRE CONTENT • STRUCTURE • TWIST • PLY • COLOR • FINISHES • STRENGTH • SIZE
Fiber Content • Characteristics of cotton thread: • Soft • Strong and durable • Easily adjusts to changes in the fabric (such as shrinkage) since it is a natural fiber • Available in various thread weights • Easy care
Advantage of Cotton Thread: • It gives uniformity in stitch & seam appearance • Dying is easy and easily gets the color of the fabric. • Resistance to the heat • Resistance to the tangling • Disadvantage: • Poor elasticity • Poor abrasion resistance • More expensive • Weaker (time consuming due to thread breakage) • Weakens easily by chemicals used in fabric &garment finishing • But for contrasting stitch polyester is good.
Rayon • Characteristics Of Rayon • High sheen • Soft, and works well in detail • Relatively heat resistant • Not colorfast • Not as strong as polyester • Less durable than polyester Nylon • Characteristics Of Nylon • Strong • Low melting temperature. Not heat resistant. • Not colorfast. Will yellow over time. • Becomes brittle through laundering
Polyester • Characteristics Of Polyester • Durable. Designed for heavy duty use • Stronger, more tensile strength than rayon • Colorfast • Retains shape • Recovers stretch • Spun poly is strong, with a matte appearance
METALLICS • Quality metallic thread has the following components: • Nylon core.. • Rice paper construction. • Outer coating. • Lower end metallic threads have no outer coating. • A good metallic has an outer coating which reduces friction and acts as a protective layer.
Thread Structure Spun yarns twisted together:- • Single yarns are twisted together to form multiply • Number of ply may be 2 to 6 • Abrasion resistance varies on type of fibers • Spun polyester is one of the most popular among the least expensive threads • Large diameter cotton replaced by small diameter polyester reduces puckering
Filament threads:- c) monofilament thread a) smooth filament b) textured filament thread Neutral color & translucent(matches with the fabric easily) Strong and minimum Breakage and inexpensive The flexibility of the thread is less therefore Causes wear & tear on machine Smoother thread are being tried to produce Nylon, polyester High tensity Used for shoes, leather garment, industrial products-tents,box cover etc Usually polyester Used for looper as cover stitches Bulk of thread may increase friction
CORESPUN THREAD:- • Multiply construction • Polyester filament core wrapped with cotton fiber • Gains strength of polyester and sewability of cotton • Polyester is not wrapped as it is suspectable to the heat • Costlier due to more dye baths to give uniform color to the thread AIR TANGLED THREAD: - • Is made from continuous filaments of polyester that are entangled as they pass through a high pressure air jet. • twisted, dyed, and wound on cones with lubricant. • used in everything from seaming flags to heavy denim jeans.
TWIST: • "S" direction or right twist for single strand yarn (such as spun) • "Z" direction or left twist for ply yarn (such as core and twisted multifilament) • SNLS (Single Needle Lock Stitch) machine is designed for the Z twist. • DNLS (Double Needle Lock Stitch) machine uses both S & Z twist for the balance. • S twist is better for flat stitch or cover stitch. • Correct twist balance essential for preventing kinking & snarling effect.
PLIED THREADS:- • Made by plying the yarns together • Plying increases the durability & performance of the thread. Carded thread:- When two or more plied thread are plied together & multiple plies twisted together.
COLOR: Color fastness Color matching • Instruments used for the color matching:- • Spectrometer • Computer shade recipes Resistance of the thread to various fading forces e.G. Sunlight, washing etc. Tests are developed by AATCC. Polyester sewing threads dyed with disperse dyes shows best color fastness.
FINISHES:- Gassed Glazed Mercerized Bonded Soft • Advantages Of Finishing:- • Threads are bonded to increase ply security & smoothness. • Prevents splitting & fraying which causes breakage.
THREAD LUBRICATION: • To reduce amount of friction • To provide protection from the needle heat • Lubricant should be non-sticky, non-staining, non-soiling • and shouldn’t effect the thread color.
Thread size measurement Weight Natural fibre such as cotton and silk Length measurement Denier. Synthetic fibres Tex. Conversion 40 weight = 225 denier = tex 25
Thread Put-ups • Spool • Cop • Cones • vicone • Container • Cocoons • Prewound bobbins
SEWING MACHINE NEEDLE Functions of the needle • To produce hole in the material • To carry the needle thread through the material and there form a loop • To pass the needle thread through the loop
Shank • upper part of the needle • may be cylindrical or have a flat side. • support • larger in diameter than the rest of the needle for reason of strength • Shoulder • intermediate between shank and the blade • It is also called shaft
Blade • below the shoulder of the blade to the eye of the needle • longest part of the needle. • greatest amount of the friction .
Long Grove • provides a protective channel in which the thread is drawn through. • A Correctly shaped long groove of a depth matched to the thread diameter, offers considerable protection to the thread. • Short Groove • It extends a little above and below the eye • Its function is to assist in the formation of the loop in the needle thread.
Eye • It is the hole extending through the blade from the long groove on one side to the short groove on the other • The shape of the inside of the eye at the top is critical.
Scarf or Clearance cut It is the recess across the whole face of the needle just above the eye. Point Best penetration Tip It is extreme end of the point which combines with the point in defining the penetration performance.
IF THE NEEDLE IS TOO SMALL FOR THE THREAD • not pass freely through the eye • not fit properly into the long groove. • Thread will suffer from excessive abrasion. • Can lead to costly thread breakages in production. • IF THE NEEDLE IS TOO LARGE FOR THE THREAD • There will be poor control of the loop formation which may cause slip stitches. • It will create holes in the fabric which are too big for the stitches and give an unattractive seam appearance. • Tends to give rise to damaged fabric along the stitch line, and in closely woven fabrics, pucker along the seam line due to fabric distortion.
Needle points Cut point Sharp tips Used for sewing leather and plastics Modifies set of stitching and appearance of seam Creates decorative effects Narrow wedge point Cuts at right angle to seam direction High stitched density is achieved Most frequently used
B) Narrow reverse twist point • Produces incisions at 45 degrees to seam direction • `seam slithly turned left on the surface of the material • Next frequently used • C) Cross Point • Incisions along line of seam • Requires large stitch length • Incisions spaced far apart • Heavy decorative seams • Stitches- straight appearance
Cloth point needle • Used for sewing textile materials • Types of cloth point needle • Set point needle • Ball point needle
Set point needle Slim set point Set point Heavy set point
Ball point Light ball point Medium ball point Heavy ball point
Denim • has a very sharp, acute point with a slender eye and a strong shaft. • penetrate heavy fabrics like denim and canvas. • The slender eye holds the thread in place for proper loop formation. • prevents deflection of the needle • insures accurate needle placement for stitch formation
Embroidery • Has a light point • Large eye • Special scarf to protect threads
Leather • has a wedge shaped point • good piercing strength
Curve needles • Used for blind stitches • Operate at high speeds • Costly
Metallic • Have a large, elongated eye • Larger scarf • larger groove to protect fragile metallic threads during stitch formation.
Quilting • Has a tapered point for stitching through multiple layers and across seams. • The shape of the point minimizes damage to the quilting fabric.
Microtex • Sharper than the universal point with a more slender shaft. • Used primarily on fine woven, heirloom sewing on very fine fabrics, synthetic suede, tightly woven fabrics.
Topstitch • Used for embroidery and quilting. • has an extra large rectangular-shaped eye which allows for smoother movement of thread. • has a much deeper groove which works wonders with heavier threads. • The deeper groove allows a heavier thread to lie in it, thereby reducing friction on the thread as it moves. • most popular sizes are 90/14 or 100/16.
Hem stitch Wing Needles • Uses: Hemstitching or heirloom embroidery on linen and batiste.Configuration: Has fins on sides of shank to create holes as you sew.Troubleshooting: Stitch is more effective when needle returns to same needle hole more than once. If needle pushes fabric into needle hole, put stabilizer under fabric.
Twin (double) Needle • Uses: Topstitching, pin tucking, and decorative stitching.Configuration: Two needles on single shaft produce two rows of stitches. Measurement between needles ranges from 1.6mm to 6mm, and needles come with universal, stretch, embroidery, denim, and Metallica points.Troubleshooting: Be sure throat plate allows for distance between needles.
Triple Needle • Uses: Same uses as for double needle.Configuration: Cross bar on single shaft connects three needles to sew three stitching rows. Comes with universal point in 2.5mm and 3mm widths.Troubleshooting: Same as for double needle.
Spring Needle • Uses: Free-motion stitching with dropped feed dogs.Configuration: Has wire spring above point to prevent fabrics from riding up onto needle, eliminating need for presser foot.Troubleshooting: Before using, practice free-motion stitching with heavy regular needle, paper, and dropped feed dogs. Don't pull paper/fabric; instead gently guide it through stitching. Wear safety glasses for free-motion work, since needles often break.