Seams and Stitches
A seam is defined as a line over which two or more fabrics are superimposed over each other. A seam may also contain the row or rows of stitching threads used to superimpose the fabrics.
A stitch is how an interlacing threads move over and between the two or more superimposed fabrics, joining them. Stitch is also applied at the edges of the fabric to avoid unraveling of ends.
Classification of Seam
- Super-imposed seams.
- Lapped seams.
- Bound seams.
- Flat seams.
- Decorative seams.
- Edge neatening seams.
Super-Imposed Seams: A category of seams in which two or more piles of fabric are overlaid, one on the top of other with raw edges aligned and sewn together at the designated distance from the raw edges, with one or more rows of stitch.
Applications: Side seams of skirt, in seams of jeans, dress stacks, finishing belt ends, attaching elastic to waistline, ends of waist bands on jeans, collars or cuffs, seamed and stitched.
Lapped Seams: A category of seams in which two or more piles of fabric are overlapped with raw edges exposed or the seam allowance is folded under and stitched with one or more rows of stitching.
Applications: Main seaming of denim jackets, jeans, and overalls. Fabrics that will not ravel, unlined garments, side seams of shirts, joining lace to another fabric, attaching patch pockets, decorative finish.
Bound Seam: A bound seam class is formed by sewing one piece of fabric or binding as it encompasses the edge of one or more pieces of fabric.
Applications: Finishing necklines, sleeves hems, inside waistbands of trousers and pants, finishing seams on unlined jackets and coats, adding interest as a design or decorative detail, finishing raw edges, continuing the motif design of lace.
Flat Seam: 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.
Applications: Close fitting garments where the seam allowance may put pressure on the body, high-stretch fabrics, athletic apparel, shape wear, undergarments, and swimwear.
Decorative Seam: This seam is made using machines with zigzag capability. 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).
Applications: Adding a design detail, cording, piping, tucking, welting, box or inverted pleating, decorative stitching, etc.
Edge Neatening Seam: A category of seam constructed with one or two plies of fabric used to finish the edge of a garment or item. There are three finishing types within the classification.
1. Secures a folded edge to the shell fabric by stitching, either on the face or back.
2. Stitching is used at the edge or to cover the raw edges, and may or may not be folded.
3. Applies a binding on a single ply of a seam allowance to finish raw edges.
Applications: Bottom and side hems of shirts, trousers, raw edges of apparels, etc.
Classification of Stitches
- Class 100 Chain Stitches
- Class 200 Hand Stitches
- Class 300 Lock Stitches
- Class 400 Multi Thread Chain Stitches
- Class 500 Over Edge Stitches
- Class 600 Covering Chain Stitches
Class 100 - Chain Stitches
Chain stitches are produced by one or more needle threads and are characterized by interloping. One needle thread is passed through the fabric, form needle loop and is secured by the next loop formed by the same thread.
Chain stitch is elastic and thicker than lockstitch and can easily be ravelled. Particular care is required to prevent run back from the last stitch, Used for temporary stitching or for blind stitching.
Applications: Hemming, Belt Loops, Padding Operations and Felling.
Types of Chain Stitches: Type 101, 103 and 104
Type 101 - Formed with only one thread introduced from one side of material only.
Type 103 - Formed with one thread and a curved needle which passes from left to right, entering and exiting from same side of material carrying a needle thread which is intercepted by a blind looper.
Class 200 - Hand Stitches
This type is originated from hand stitches. It is produced from a single thread. This thread is passed through the fabric from one side to another and the stitch is secured by the single line of thread passing in and out of the garment.
Applications: Stitching of costly dresses, jackets, sample garments, etc
Types of Hand Stitches:
Running Basting: Temporary and decorative purposes.
Back stitch: Used whenever strength is important.
Diagonal Basting: Useful for slippery fabrics.
Buttonhole stitch: Decorative of functional depending on closeness of stitch.
Class 300 - Lock Stitches
This type of stitches is produced with two or more groups of threads. Here the two threads are joined by interlacing. Loops of one group are passed through the material and are secured by the thread of second group. One group is referred as needle thread and other as bobbin thread. This stitch has enough strength and same appearance on both sides.
Applications: Underwear, most types of apparels, decorative purposes.
Types of Lock Stitches: Type 301, 304, 308 and 309
Type 301 - Two threads, one needle and other bobbin thread. Loop of needle thread passes through material and interlaced with bobbin thread.
Type 304 - The construction is similar to type 301, but the needle bar moves as the material is fed giving a zigzag stitch.
Type 308 - Double step zigzag lockstitch.
Class 400 - Multi thread chain stitch
This class is formed with two or more groups of threads. Loops of one group of thread are passed through the material and are secured by interlacing and interloping with loops of another group. Here on group is called needle thread and another group looper thread. It has an appearance of lock stitch on the top but has a double chain effect formed by a looper thread on the under-side.
Applications: Used for setting elastic in waist bands, decorative stitching on belts.
Types of Multi thread chain stitches: Type 401, 404 and 406
Type 401 - Loops of needle thread are passed through materials and interlaced with loops of bobbin thread. These interloping are drawn up against underside of material.
Type 402 - Zigzag chain stitch, construction is same as type 401, but needle bed moves as material is fed.
Type 406 - Two needle threads interlace with one bobbin tread, which are then drawn up underside of material.
Class 500 - Over - edge chain stitch
The stitch type in this class is formed with one or more groups of threads. Here at least one group of thread passes around the edge of material. So no thread from the fabric can come out. The most frequently used stitch of this type have one or two needle threads and one or two looper threads and thus forms a narrow band of stitching along the edge of the fabric.
Applications: Edge neatening of knitted fabrics, where extensibility of stitches in important. Polo tees, sports wear, dance wear garments.
Types of Over Edge chain Stitches: Type 503, 504, 512
Type 503 - Two threads, needle thread passes through material and is brought to edge where it is interlaced with bobbin threads. Edge of fabric is sealed.
Type 504 - Three threads, one needle and two lower bobbin threads. Needle thread interloops with one bobbin thread, then the first bobbin thread loop is interlaced with second bobbin thread.
Type 504 - Four thread over edge chain stitch.
Class 600 - Over-edge chain stitch
This type of stitches is generally produced with three groups of threads. Threads of two groups can be seen from either side. The first group of thread is called needle thread, second is called top cover thread and the third is called bottom cover thread. The stitches of this class are very complex and up to 9 threads can be used in producing these stitches.
Applications: Knits, Lingerie, binding elastics, decoration, etc.
Types of Over - Edge Chain Stitches: Type 602, 605, 607
Type 602 - Formed with four threads, two needle threads, one bobbin and one cover threads. Needle threads are passed through loops of covering threads on material surface and interlace with bobbin thread at underside of material.
Type 605 - Five threads, three needle, one covering and one bobbin threads. Construction is same as type 602.
Type 607 - Six threads, four needle threads, one covering thread and one bobbin thread. Construction is same as 602 and 605.
1 yorum:
This guide is very helpful for many people. Keep doing nice work.
Yorum Gönder