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  • Seam
  • Prepared By : Mazadul Hasan sheshir ID: 2010000400008 13th Batch (session 2009-2013) Department : Wet Processing Technology Email: mazadulhasan@yahoo.com Blog : www. Textilelab.blogspot.com (visit) Southeast University Department Of Textile Engineering I/A 251,252 Tejgaon Dhaka Bangladesh Prepared By : right
  • Seam in Garments Seam types are the place where two pieces of fabric are joined by application of a series of stitches or stitch types with a defined geometry. Over the years there are a number of different types of seams that have been developed to do different jobs. Many have largely been superseded by the development of machine stitches that finish as you sew them, and by the development of the over locker (or serge in some parts of the world), it is useful to know some of the basic seams types and finishes. Seam in Garments
  • A seam is made when two or more layers of fabric are stitched together. Its the line that is formed by sewing together pieces of cloth. Stitches used to make such a line. Seam
  • Seam Types: 1. Class-i, superimposed seam. 2. Class-ii, Lapped seam. 3. Class-iii, Bound seam. 4. Class-iv, Flat seam. 5. Class-v, Decorative seam. 6. Class-vi, Edge Neatening seam. 7. Class-vii, like as Lapped seam. 8. Class-viii, Class 8. Types of Seam
  • Types of Seam
  • Stitch Vs Seam
  • Superimposed Seam (SS): The superimposed seam is achieved by two or more separate pieces of together. This is the one of the most common method of seaming. The most basic superimposed seam is made when one ply of fabric is stacked upon another with thread stitching through all plies of fabric. Variations are plain seam, French seams and Double machine seam. Lapped Seam (LS): Lapped seam is made with two or more pieces of fabric overlapping each other. LS commonly, but not always, have one ply of fabric fold under itself for a finished edge. Lapped seams are common when sewing side seams on jeans and dress shirts. This class of seaming has the largest number of variations. Bound Seams (BS): Bound seam is made to finish and edge of a garment. A common example of this would be a neckline of a Crew T. A bound seam is one piece of fabric encompassing the raw edge of another piece of fabric. There are many variations of a bound seam. COMMON TYPES OF SEAMS
  • Flat Seam (FS): A flat seam is constructed by having two pieces of fabric meet precisely at their edges. A cover stitch is used to sew the two pieces of fabric together. This stitch has multiple needles and creates a stitch perpendicular to the seam line. This creates a flat seam. Plain seam is a flat seam. Edge Finished Seams (EF): This seam is used to prevent the edges of the fabric from rolling or curling. Primarily used for knit fabrics and is suitable for straight or curved seams and edges. Ornamental Seam (OS): this seam is made using machines with zigzag capability. It is used on a plain seam on woven or knit fabric. The zigzag stitch length (coverage) must be adjusted to accommodate and prevent fabric from raveling. The more the fabric ravels, the closer together the stitches need to be (tighter or shorter stitch length). COMMON TYPES OF SEAMS
  • Significance and Use Selection of correct seam type for a particular assembly is very important as improper selection of stitch type, seam type or thread type can result in failure of the sewn seam and failure of the garment. The most important aspect of a properly constructed sewn seam is strength, elasticity, durability, security and appearance. These characteristics must be balanced with the properties of the material to be joined to form the optimum sewn seam. The selection of the seam type and stitch type should be based upon these considerations. Strength: The seam efficiency of the sewn seam should be so that sewn seam strength is balanced and can withstand the everyday usage of the garment. Elasticity: Elasticity of sewn seam should be slightly greater than that of the material which it joins. This will enable the material to support its shape of the forces encountered for the intended end use of the sewn item. The elements effecting the elasticity and strength of a sewn seam depends upon fabric type and strength, seam type, stitch type, stitch density (SPI), thread tension, and thread strength and elasticity. SIGNIFICANCE AND USE OF SEAM
  • Durability: Durability of a sewn seam depends largely upon its strength relative to the elasticity of the seam and the elasticity of the material. For making durable sewn seam, the thread size and stitch density must be carefully chosen to avoid puckering. Security: Security of sewn seam depends chiefly upon the stitch type, SPI, and its susceptibility to become unraveled. The stitch must be well set to the material to prevent snagging that can cause rupture of the thread and unraveling of certain stitch types. Appearance: Appearance of a sewn seam generally is governed by the proper relationship between the size and type of thread, the stitch density, and the texture and weight of the fabric. There are a number of different types of seams that have been developed over the years to do different jobs. While many have largely been superseded by the development of machine stitches that finish as you sew them, and by the development of the over locker (or 'serge' in some parts of the world), it is useful to know some of the basic seams types and finishes. SIGNIFICANCE AND USE OF SEAM
  • A TABLE FOR DIFFERENT TYPES OF SEAM & THEIR EXAMPLE
  • SUPERIMPOSED SEAM Seam Class-1 : Superimposed seam The superimposed seam is used to join two or more pieces of material (fabric or otherwise) together. It is created by one ply of fabric being stacked (superimposed) upon another with their right sides (the one that will show when the item is worn or used) together and using thread to stitch through all layers. This is one of the most common and simplest methods of seaming and is used to construct most commercial garments. Usage: 1. Side seam of basic pants. 2. Side seam of shirts.
  • Usage: 1. Inner seam of long sleeve. 2. Side seam of jeans etc. Seam Class-2 : Lapped seam This class of seaming has the largest number of variations. This type of seam is produced by overlapping of two raw edges of the fabric and at least one of the edge must be neatened in a decorative manner, by using two or more rows of zigzag stitching. LAPPED SEAM
  • Seam Class-3 : Bound seam The purpose of a bound seam is to finished the raw edge of a garment. A common usage of this finish is seen on the neckline of a collarless garment made of woven fabric. A bound seam is made by using one piece of usually bias-cut fabric to enclose the raw edge of another piece of fabric. There are many variations of a bound seam. Technically this is a finishing method, rather than a seam. Usage: 1. To attach elastic in the edge of garments. 2. In Neck edge of basic T-shirt, waist band, womans blouse, babys nightgown, child bishop dress, camisole etc. BOUND SEAM
  • Seam Class-4 : Flat seam In this seam type, fabric edges buttled together without causing any gap and joining across by a stitch, which has two needles sewing into each fabric ancovering threads passing back and forth between these needles on both sides of the fabric. Usage: 1. Hem of knitted underwear. 2. For decorative garments items. FLAT SEAM
  • Seam Class-5 : Decorative seam The seam in this class is produced by decorative stitching across a garment panel, where single or multiple rows of stitches are sewn through one or more layers of fabric. These several layers can be folds of the same fabric. Usage: 1. To produce gathering on fabric. 2. To make pleat in the garments. 3. To attach ribbon etc. DECORATIVE SEAM
  • Seam Class-6 : Edge neatening seam Seam types in this class include those, where fabric edges are neatened by means of stitches (over lock stitches) well as folded hems and edges. Usage: 1. In side edges of a pants side seam. 2. Hems of skirt, shirt etc. 3. Button holes. EDGE NEATENING SEAM
  • Seam Class-7 : Like as lapped seam When additional part such as elastic , lace etc are attached to the fabric then Seam Class-7 is used. Seam in this class relate to the addition of separate items to the edges of a garment part. They are similar to the lapped seam, except that the added component has a definite edge on both sides. Usage: 1. Inserted elastic on the leg of a swimming dress. 2. Band and lace attachment to the lower edge of sleeve. 3. Elastic braid on the edge of the bra. LIKE AS LAPPED SEAM
  • Class 8: Final seam class, where only one piece of material need to be involved in constructing the seam. Usage: 1. Belt loop as used on jeans, rain coat. 2. Loop for braid penetration in child