1. The document discusses different types of sewing machines and their uses, including manually operated machines for domestic use and electrically operated industrial machines for garment production. 2. It describes various sewing stitches like lockstitch, chainstitch, zigzag stitch and their classifications. Physical properties of ideal seams like strength, durability and appearance are outlined. 3. Common sewing problems are explained, such as slipped stitches, staggered stitches and seam pucker formation. Causes and remedies for these problems are provided.

1. TE 309/TEX 309 : Apparel Manufacturing-ii
Chapter 1
Garment Sewing Section
Course Teacher
Mohammad Ashraful Alam

2. Sewing Machine

3. Sewing Machine

4. Types of Sewing Machine
 According to the operating system
1. Manually operated sewing machines :
 Driven by physical energy.
 Used for domestic and tailoring purposes.
 Less production, but more laborious.
 Low cost.
2. Electrically operated or Industrial sewing machines :
 Usually driven by electric power.
 High productivity.
 Used in garments industry.
 Cost is high.

5. Different Sewing Machines….
1. Lockstitch Sewing machine
2. Chainstitch Sewing machine
3. Zigzag Lockstitch machine
4. Flatlock Sewing machine
5. Overlock Sewing machine
6. Blind Stitch machine
7. Button hole machine
8. Button attaching machine
9. Bartack machine
10. Feed of the arm machine

6. Stitch & Seam
Stitch is a Unit or Loop in a seam. Which is
produced by three principle Inter looping,
Intra looping, Inter lacing.
A seam is a line where two or more fabrics are
joined.

7. Stitch

8. Stitch Classes
1. Stitch Class-100 (Single thread chainstitch).
2. Stitch Class-200 (HandStitch).
3. Stitch Class-300 (LockStitch).
4. Stitch Class-400 (Multi thread chainstitch).
5. Stitch Class-500 (Over lock stitch).
6. Stitch Class-600 (Covering chain stitch).

9. Stitch Class 100 (Single thread chain
stitch).
1. In this stitch -one loop passing through another
loop of same thread.
2. Security of this seam is poor/not satisfactory.
3. Only one needle thread is used for making this
stitch.
4. It is also used blind stitch purpose.
Usages:
Hemming, button attaching, button holing, gathering
and temporary positioning of garment component
and purpose.

10. Stitch Class 200
 This stitch is produced for longer
length sewing.
 Usefor costly garments.
 Need more time and skilled operator.
Uses: Lapel of Blazer, collar of shirt, saddle stitchetc.

11. Stitch Class 300
1. Both Sides are same.
2. Less extensibility.
3. Bobbin capacity is less.
4. High Security.
5. It requires two types of sewing thread.
6. More compact.
7. It is widely used in garments factory.
 Usages:
Lock stitch is extensively used for joining fabrics
collar, cuff, pocket, facing etc. Top stitching is
used for button holing, attaching, blind stitching
etc.

12. Stitch Class 400
1. Security is higher than lock stitch.
2. One or more thread is used.
3. One group is called upper thread and another group is
called looper thread (under thread).
4. Higher production than lock stitch due to use large
package.
5. It is widely use for making knitted garments.
Usages:
Hemming, inside seam of jeans

13. Stitch Class 500
1. Toprevent fraying out of lossyarn.
2. Useto make knitted garments.
3. Also use for decorative purpose.
Usages:
Edge neatening, decorative purposes

14. Stitch Class 600
1. At least three (1n+2l) set of thread are use.
2. This stitch is use in undergarments to attach
lace, braid or elastic.
3. This Stitch is also use to join side by side of
fabric without increasing thickness.
Usages:
Bottom hem, elastic joining

15.  Superimposed seam
 Lap seam
 Bound seam
 Flat seam
 Edgefinishing
 Decorative Seam
 Applied Seam
 Others
Superimposedseam
Boundseam
Lapseam
FlatseamEdgefinishing
Seam Types

16. Physical Properties of Seam
 Strength: a seam must be strong. Strength is usually measured in two
directions: across the seam (lateral or transverse strength) and along
the seam (longitudinal strength).
 Extensibility
 Durability: A seam must be durable, long-lasting and not abrade or
wear easily during everyday use of the garment
 Security: a seam needs to be secure and not unravel during everyday
use of the garment
 Appearance properties: the ideal seam should join pieces of fabric
in an unobtrusive and efficient manner with no discontinuity in physical
properties or appearance.
 Balance

17. Stitch Properties
 Stitch size has three dimensions: length, width, and depth.
 Stitch length is specified as the number of stitches per inch (spi) and
can be an indicator of quality. High spi means short stitches; low spi
means long stitches. Generally, the greater the spi, the more the
holding power and seam strength.
 Stitch width refers to the horizontal span (bight) covered in the
formation of one stitch or single line of stitching. Stitches that have
width dimensions require multiple needles or lateral movement of
thread carriers such as the needle bars, loopers or spreaders.
 Stitch depth is the distance between the upper and lower surface of the
stitch. It is a factor for blind stitches.

18. Sewing Machine Feed
Mechanism
1. Drop Feed Mechanism
2. Differential Bottom Feed Mechanism
3. Adjustable top Feed Mechanism
4. Needle Feed Mechanism
5. Puller Feed Mechanism
6. Unison Feed Mechanism

19. Sewing Needle

20. Function of 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

21. Sewing thread needle parts
•BUTT
•SHANK
•SHOULDER
•LONG GROOVE
•SHORT GROOVE
•EYE
•NEEDLE POINT
•SCARF
•BLADE

22. Sewingproblems
Sewing problems consist of-
• Problem of stitchformation.
• Seampucker.
• Fabric damageat the seamline.

23. 1. Problemsof stitchformation
a) Slipped stitch: If the upper thread in continuous stitches can
not pick the lower thread i.e. binding miss during stitch
formation is called slipped stitch.
Causes:
– Loop size or needle is small.
– Needle deflection or bending.
– Tension variation in lopper and needle thread.
– Hook or lopper or needle is not able to hold the thread loop in
proper time.
Remedies:
– Timing of (hook or lopper) with needle should be adjusted
properly.
– Adjust needle and thread size.
– Adjust tension property.
– Change of thread.

25. Continued……..
b) Staggered stitch: If the stitches produced by needle are not parallel
with the seamline, staggered stitchesformed.
Causes:
 Needle vibration or deflection.
 wrong needle point.
 Not proper adjust of needle sizeand threadsize.
 Faulty movement controlling of fabric into the feed mechanism.
Remedies:
• Needle sizeshould be increased.
• Changeof needle or threadsize.
• Changeof feed mechanism.

27. Continued……..
c) Un balanced Stitch: If the interlacement of the needle thread
and bobbin thread does not takes place at the middle of two
layers of the fabric then unbalanced stitch is produced.
Causes:
 Incorrect tension of sewing thread.
 Incorrect passage of thread through the guide.
 Due to insufficient lubrication, (uneven) tension variation
increased.
Remedies:
• Adjust thread tension.
• Correct the passage of thread.
• Use good quality of thread.

29. Continued……..
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 d) Variable stitch density: If the
no. of stitch varied in the seam
line per unit length, then variable
stitch density occurred.
 Causes:
 Insufficient pressure of pressure
foot, causing uneven feeding.
 Feed mechanism is not working
properly. Improper unwinding of
thread.
 Twisting of needle in the bottom of
thread
 package.
 Fraying of thread in the needle.
More tension in the thread.
 Becoming of more heating of
thread and hook.
 Use of low quality of thread.
Remedies:
 Uses of improved feed
 mechanism.
 Increase of pressure of
presser foot.
 Proper threading of sewing
thread.
 Thread can be changed.
 Proper use of lubricant.
 Use of good needle.
 Finer thread can be used.
 Tension in thread must be
 adjusted.

30. Continued……..
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 e) Frequent thread breakage:
 Causes:
 Improper unwinding of thread from package. Higher thread tension.
 Excess needle heating. Lower quality of thread.
 Remedies:
 Reduce tension in tension in tension disc.
 Reduce thread tension.
 Use of strong yarn.
 Change the needle if required.
 Use coarser needle.
 Use of high quality needle.
 Use lubricant.
 Use needle cooler.
 Confirm oil supply.
 Change of thread.

31. Problemsof seampucker
Pucker is a wrinkled appearance along with sewing
line.
a) Unequal stretch on fabric: Causes :
• If two or more plies fabrics are sewn together, one ply will be feed
more than other and seam pucker create due to uneven stretch.
Remedies:
•
•
Improved feed mechanism of sewingm/c.
Skilled operator and fabric handling would be special process.
b) Fabric dimension
instability: Causes:
• When two or more layers of fabric are sewn together and one layer
shrinks more than after washing differential seam pucker is formed.
Remedies::
•
•
Shrinkagedifference must be lessthan 2%.
Weshould test shrinkage of two types offabric before sewing.

33. Continued………
c)Extension in sewingthread:
Causes:
• While sewing threads are subjected to tension and for tension thread
will be extended and after sewing when thread get chance of
relaxation then seam pucker formed.
Remedies:
•
•
Tensionof the thread should be kept aslow aspossible.
Bychanging the sewing threads.
d) Sewing thread
shrinkage: Causes:
• After sewing, if the sewing threads shrinks due to wash or iron, then seam
pucker occurred.
Remedies:
•
•
Shrinkage of sewing thread must be equal to the fabric shrinkage.
Before sewing, the shrinkage property of both thread and fabric
should be known.

34. Continued……..
e) Fabricconstruction:
Causes:
• In a compact fabric high EPI and PPI, while sewing of such
fabrics, the threads are displaced around the needle and
because of lack of space, pucker may be seen along the holes
created by the needles.Remedies:
•
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Very difficult to overcome this type of problem but to reduce
the
problems following steps should be taken:
By using fine / thin needle and fine / thin thread. Reduction of stitch
density.
Change the fabric if possible.

35. 3.Fabricdamageat the seamline
Causes:
•This type of fault is mainly due to needle specially bent or
damaged needle.
•For this fabric damage, sewing strength becomes low and due
to more fabric damage, fabric may be tear off at the sewing
line.
•Fabric may be damaged with new and good needle if needle
size
and needle selection is wrong.
•This fault is visible after washing and wear.
Two types of fabric damage can be occurred with needle at the
seam line:
•Mechanical damage.
•Needle heating damage.

36. Continued……….
a)Mechanical damage: To minimize the damage, the following steps
are taken:
• Needle size and point should be properly selected.
• M/c speed should be reduced.
• Application of lubricant.
• Test the sew ability before sewing of fabric.
b)Needle heating damage:
• The temperature in needle due to friction between needle
and fabric
is up to 300 – 350°C. In this temp, needle or fabric both
may be damaged. We can solve the problem by-
Less speed of machine, proper needle size and shape, short length of
sewing, cool air use, lubrication.