International Design Journal Volume 4 Issue 3 Technical Issues

Effect of Thread Type and Tension Control on Cotton Fabric

Sewability
Nashwa Mostafa Hafez Mohamed
Assistant Professor, Apparel Department, Faculty of Applied Arts, Helwan University, Egypt
Nesreen Nasr Eldeen Hassan
Assistant Professor, Apparel Department, Faculty of Applied Arts, Helwan University, Egypt

Abstract:
Thread plays an important role in the apparel manufacturing process. When the thread is stronger than
the material that it is being used to join and if seams are placed under stress the material may tear
before the thread breaks. Garments are usually sewn with threads of lesser strength than the fabric so
that if stressed the seam will break before the garment.
Tension control is also a very important element that is used to adjust how loose or tight sewing
stitches are. Top thread and bobbin thread should be meeting between the two layers of fabric. If the
top thread is not going into the fabric, the tension should be loosen; and vice versa, if the bobbin
thread is not going into the fabric the tension should be tighten. Thread runs between various tension
disks, and the amount of tension which is set by the regulator will determine how much pressure these
disks put on the thread. In this study five different tensions are applied on four types of thread by using
super imposed seam. These seams examined for thickness, stiffness, seam appearance, seam pucker,
tensile strength and extensibility according to standards. Tests took place into conditioned atmosphere
of 21C and 65% RH. Comparisons have been made among the five different tensions and the four
different thread types this was done with reference to seamed lines durability, efficiency and
appearance.
Keywords:
Thread, spun thread, filament thread, tension control, sew ability

1. Introduction threads are produced with three finishes: soft,

Sewing thread is usually less than 1/1000th of glace and mercerized. Soft finish threads receive
the weight of apparel, but it carries more one half no additional processing except bleaching and
the responsibilities for its performance. (1) dyeing. Used on inexpensive garments, they are
Threads are used to form the stitches that hold relatively inexpensive with good suability but
the fabric parts together. They can be described because they have a high shrinkage, seam
by fiber type, construction, and size. Threads can pucker. This is frequently problem after washing.
be made from a single fiber type such as cotton, Glace' threads are treated with wax and special
linen, silk, rayon, nylon, polyester, or rubber or chemicals for a hard, glossy finish. They are
from a combination of fibers such as stronger, more resistant to abrasion, and stiffer
cotton/polyester. (2) than other cotton threads. They are available in a
1.1. Classification of sewing thread according limited color selection and used for gathering
to fiber type and for sewing heavy materials, leather, vinyl,
1.1.1. Natural fiber threads the most common and canvas. Mercerized threads are treated with a
natural fiber used for threads, cotton threads. caustic solution to create a smooth, strong,
They have excellent suability with little kinking lustrous thread. They are frequently used on
or skip stitching. They are rarely affected by hot cotton garments that will be dyed. (4) Linen and
needles a common element of high-speed sewing silk threads are rarely used because of their high
machines and even sew well on poorly adjusted cost. (3)
machines. (1) Cotton threads dye well, and since 1.1.2. Synthetic fiber threads the most common
they mold to the fabric better than other fibers, synthetic threads, polyester and nylon, were
they are particularly attractive for topstitched developed to perform well on synthetic fabrics
elements. Compared to synthetic threads, their and withstand the chemicals and heat of durable
strength and resistance to abrasion is inferior, press treatments. (2) Compared to cotton threads
and they shrink and mildew when wet. (3) Cotton of the same size, they are stronger, more resistant

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to abrasion, mildew and ultraviolet radiation, and hemming and surging inexpensive garments and
have less shrinkage. Household textiles. (8)
1.1.3. Blended fibers threads One of the most 1.2.4. Textured threads made of multifilament
common threads in use today is a combination of that have been crimp textured or bulked by
cotton and polyester, which combines the sew twisting, crimping and untwisting, textured
ability of cotton with polyester's strength and threads have a soft land, good coverage and
resistance to abrasion. (3) elasticity. (7) The most common use of textured
1.2. Classification of sewing thread according threads is in the over edge and cover stitch
to construction machines; however, very fine sizes can be used
Although there are a variety of thread as needle threads on chain stitch and over edge
constructions, most threads used in garments are machines. They can also be used as bobbin
twisted, core spun, monofilament, or textured. (2) threads to add moderate stretch to a lock stitched
1.2.1. Twisted threads All natural fibers, with seam. (9)
the exception of silk, begin with fibers - short 1.3. Classification of sewing thread according
lengths of staple, which are twisted together to to thread size
make a single-ply thread. Then two or more plies The thread size is dependent on many factors-
are twisted together in the reverse direction to such as the fabric weight and type, stitch and
make a sewing thread with a balanced twist. seam type, machine speed, needle size, end use,
Without this balance, the thread could not be and seam strength. Most threads are sized using
controlled. Most threads are finished with a "Z" Tex system or the cotton count system. (2)
or left twist because the action of the lockstitch 1.4. Factors in thread selection
machine would cause threads with an "8" twist to Garment design, type, quality, end use, and
unwind One exception is the double-needle life expectancy.
lockstitch, which has two bobbins one revolving Desired strength and durability.
to the left and one to the right. This type of Fabric weight and type.
machine requires threads with both twists. (5) Stitch and seam type, number of stitches/inch,
Spun cotton thread is manufactured with a great machine speed, and needle size.
degree of care and professionalism. Its the most Cost. (10)
widely-used natural fiber; highly-versatile cotton 1.5. Tension control
is known for its strength and comfort and is used Control and adjust sewing machine tension
in an amazingly wide variety of textile empower to sew creatively. Sewing thread in
materials. (6) machine must feed through three main points;
In addition to the natural fibers, polyester, silk, the tension disks, the take-up, and the needle.
and nylon filaments cut or broken into staple The bobbin must also be threaded properly to
lengths. (5) Spun polyester thread is the most enable the machine to form a good stitch.
common. Sometimes referred to as PP or PP Bobbins have their own mechanism for
Spun, are made by spinning 100% polyester controlling tension on the thread.
staple fibers into yarns and then plying these Upper and lower tensions must be balanced to
yarns into a sewing thread. They are normally produce a perfect stitch. The upper tension varies
made in two or three ply constructions depending in location on different machines. It may be on
on the yarn size. (6) the faceplate, on the front of the needle-bar
1.2.2. Core spun threads begin with a housing, or on the upper arm of the machine
continuous filament of polyester, which is then head. It is usually adjusted with a dial. The lower
wrapped with a cotton or polyester sheath to tension, located on the bobbin case, may be
make a single-ply thread. Then the two to four adjusted by a screw.
plies are twisted together to make the sewing Lower tension should only be adjusted if the
thread. (7) Cotton/poly threads have the advantage problem cannot be fixed by adjusting the upper
of better sew ability, while poly/ poly threads can tension.
be dyed in a one-step process. (8) As shown in fig.1 a perfect stitch will have
1.2.3. Monofilament threads are simply a single threads locked midway between the two layers of
filament of nylon or polyester. It is stiff, wiry, cloth, with no loops on the top or bottom of the
and unravels easily. It is uncomfortable next to seam and no puckers in the cloth. If the bobbin
the skin and harsh on machines. (7) Monofilament thread loops show on the top side of the seam
threads are translucent and reflect the fabric's and the top thread is straight, the upper tension is
color. They are used primarily for blind tighter than the lower. If spool thread loops show
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on the underside of the seam and the lower the lower.

thread is straight, the upper tension is looser than
Balanced Tension

Upper Tension Too Tight

Upper Tension Too Loose

Fig.1. Effect of tension control on sewing stitches. (11)

2. Experimental work The following table1 illustrates the specifications
2.1. Fabric specifications of the tested fabric
Table 1 Fabric specifications
Fabric type Fabric Yarn Yarn Mass Thickness
structure warp/cm weft/cm (gm/m2) (mm)
100% cotton Twill 2/1 38 24 245 0.45

2.1. Sewing thread specifications The following table2 illustrates the specifications
This study concerned with spun (cotton & of the tested sewing thread.
polyester) thread and filament polyester thread.
Table 2 Sewing thread specifications
Thread no. Thread color Thread type Thread size
1 Red Spun polyester thread Ne 40/2
2 Brown Spun cotton thread Ne 40/3
3 Green Spun polyester thread Ne 22/3
4 White Filament polyester thread Denier150/1

2.3. Sewing specifications volt, 2850 cycles per min., and 5000 stitches per
Tested samples are sewed by using Mitsubishi min.
sewing machine model LS2-1150 with speed 220
Table3 illustrates the sewing specifications.
Table 3 Sewing specifications
Stitch type Seam type Stitch Stitch Needle
density/cm length(mm) number
Lock stitch 301 Superimposed 5 2.5 12

2.4. Thread tension specifications or tight is the thread tension (as the number of
Five different tension levels are used as shown in rounds decreases thread tension increases and
table 4. Number of rounds describe how loosen vice versa.)
Table 4 Thread tension specifications
Thread Thread Thread tension3 Thread Thread
tension 1 tension 2 tension 4 tension5
2 rounds 5 rounds 7 rounds 9 rounds 11 rounds

2.5. Experimental tests obtained using Shirley stiffness tester according

All tests were done in conditioned atmosphere of to ASTM D 1388 (13). Tensile strength and
20C 2 and 65% 2 RH. Testing seams extensibility obtained using tensile tester
included thickness test which was carried out by according to BS 3320:1988 (14); average of three
using Erazier Pregision Instrument, according to readings has been obtained for each property.
(B.S.-2544). (12) Thickness of seams obtained Seam pucker has been evaluated, according to
from average of four readings. Stiffness test AATCC 88B-1978 (15) and seam appearance;
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average of five readings has been obtained for 3.1.1. Effect of thread type at different tension
each property. levels on seam thickness
3. Results and Discussion Table5 illustrates the effect of thread type at
3.1. Effect of thread type at different tension different tension levels on seam thickness
levels on seam properties
Table 5 Effect of thread type at different tension levels on seam thickness
Seam thickness (mm)
Thread Thread 1 Thread 2 Thread 3 Thread 4
tension level
1 0.97 1.03 1.14 0.99
2 0.94 1.01 1.11 0.97
3 0.92 0.98 1.07 0.94
4 1.02 1.06 1.21 1.04
5 1.05 1.12 1.27 1.08
indicate that, tension3 scored the least seam
Effect of thread type at different thickness then tension2 then tension1. This
tension levels on seam thickness can be attributed to the occurred seam pucker
by increasing the tension which increases
Seam thickness

2 seam thickness.
Thread 1 Using tension5 and4 make fabric during
(mm)

1
Thread 2 sewing uncontrolled and gathered bobbin
0 thread behind fabric which leads to more
Thread 3
increase in seam thickness.
Thread tension level
Thread 4 The thread type regression equation for
thread1 is y= 0.024x + 0.908, for thread2 is
Fig.2. Effect of thread type at different tension levels on y= 0.023x + 0.971, for thread3 is y= 0.036x
seam thickness + 1.052 and for thread4 is y= 0.025x +
0.929. Where y= seam thickness & x= thread
(As shown in table5, fig.2) it can be noticed
tension level. The thread type correlation
that thread1 gives the least seam thickness
coefficient on seam thickness is positive but
then thread4 then thread2 while thread3 gives
its significant effect in general is weak, as the
the highest value as seam thickness increases
correlation is strong when the value of R
by increasing thread size.
nearest to 1. For thread1 R = 0.4881, for
Logically by increasing thread tension seam thread2 R = 0.4648, for thread3 R = 0.5063
thickness decreases and vice versa. Duo to and for thread4 R = 0.4992.
the higher tension that tighten the seams. But 3.1.2. Effect of thread type at different tension
this didnt happen as follows. levels on seam stiffness
Despite tension level1 is very tight, tension2 Table6 illustrates the effect of thread type at
is tight, tension3 is middle tension, tension4 is different tension levels on seam stiffness
loose and tension5 is very loose, results
Table 6 Effect of thread type at different tension levels on seam stiffness
Seam stiffness (mg.cm)
Thread Thread 1 Thread 2 Thread 3 Thread 4
tension level
1 215.8 233.7 240.9 216.8
2 211.7 229.6 236.7 212.9
3 204.6 224.9 229.6 207.3
4 216.3 235 241.8 219.3
5 217.8 235.4 242.6 221.5

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Effect of thread type at different tension4 and5 differed as seam stiffness

tension levels on seam stiffness increased by decreasing thread tension. This
can be referred to the gathered bobbin thread
Seam stiffness

250 behind fabric which increased stiffness.

200 Thread 1
(mg.cm)

150
100 The thread type regression equation for
50 Thread 2 thread1 is y= 0.86x + 210.66, for thread2 is
0
Thread 3 y= 0.88x + 229.08, for thread3 is y= 0.85x +
235.77 and for thread4 is y= 1.58x + 210.82.
Thread 4
Thread tension level Where y= seam stiffness & x= thread tension
level. The thread type correlation coefficient
Fig.3. Effect of thread type at different tension levels on
seam stiffness on seam stiffness is positive but its significant
effect in general is too weak, as the
(As shown in table6, fig.3) it can be noticed correlation is strong when the value of R
that thread1 gives the least seam stiffness nearest to 1. For thread1 R= 0.065, for
then thread4 then thread2 while thread3 gives thread2 R= 0.0977, for thread3 R= 0.0624
the highest value as seam stiffness increases and for thread4 R= 0.198.
by increasing thread size. (There is direct 3.1.3. Effect of thread type at different tension
relation between thread number and seam levels on seam tensile strength
stiffness). Table7 illustrates the effect of thread type at
The fact that seam stiffness decreases by different tension levels on seam tensile strength
decreasing thread tension and vice versa,
happened in case tension level1,2 and3 while
Table 7 Effect of thread type at different tension levels on seam tensile strength
Seam tensile strength (kgf/mm2)
Thread
Thread 1 Thread 2 Thread 3 Thread 4
tension level
1 0.5494 0.4215 0.7308 0.1869
2 0.4432 0.4199 0.6874 0.1349
3 0.4306 0.4094 0.5409 0.1107
4 0.3984 0.3602 0.4915 0.0876
5 0.3279 0.2192 0.4497 0.066

increases.
Effect of thread type at different
tension levels on seam tensile Despite thread1 and2 have the same size,
strength thread1 gives higher tensile strength which
Seam tensile strength

can be attributed to fiber type as polyester is

0.8 more durable than cotton.
(kgf/mm2)

0.6 Thread 1
0.4 Thread4 scored the smallest seam tensile
0.2 Thread 2 strength duo to its filament construction,
0
Thread 3 whereas spun construction is more durable

than filament construction.
Thread 4
Thread tension level As tension level1 refers to very tight tension,
tension2 is tight, tension3 is middle tension,
Fig.4. Effect of thread type at different tension levels on tension4 is loose and tension5 is very loose,
seam tensile strength
results indicate that, there is an inverse
(As shown in table7, fig.4) it can be noticed proportional relation between seam tensile
that thread3 gives the highest seam tensile strength and thread tension level. Hence seam
strength, as thread size increases durability tensile strength increases by increasing
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thread tension and vice versa. Where tighten general is very strong, as the correlation is
seams are durable than loosen seams. strong when the value of R nearest to 1. For
The thread type regression equation for thread1 R= 0.9204, for thread2 R= 0.7319,
thread1 is y= -0.0488x + 0.5762, for thread2 for thread3 R= 0.9481 and for thread4 R=
is y= -0.0464x + 0.5053, for thread3 is y= - 0.9594.
0.0758x + 0.8075 and for thread4 is y= - 3.1.4. Effect of thread type at different tension
0.0289x + 0.204. Where y= seam tensile levels on seam extensibility
strength & x= thread tension level. The thread Table8 illustrates the effect of thread type at
type correlation coefficient on seam tensile different tension levels on seam extensibility
strength is negative but its significant effect in
Table 8 Effect of thread type at different tension levels on seam extensibility
Seam extensibility (%)
Thread Thread 1 Thread 2 Thread 3 Thread 4
tension level
1 9.045 6.944 6.167 4.778
2 9.833 7.278 6.209 5.111
3 9.945 7.889 6.389 5.611
4 10.83 8.05 6.5 5.833
5 13.89 8.89 6.94 5.984

Effect of thread type at different proportional relation between seam

tension levels on seam extensibility extensibility and thread tension level.
(Tension level1 refers to very tight tension,
Seam extensibility

15 tension2 is tight, tension3 is middle tension,

10 Thread 1 tension4 is loose and tension5 is very loose)
Hence seam extensibility increases by
(%)

5 Thread 2
decreasing thread tension and vice versa.
0 Thread 3 Loosen seams elongates more than tighten
seams.
Thread 4
Thread tension level The thread type regression equation for
thread1 is y= 1.0687x + 7.5025, for thread2
Fig.5. Effect of thread type at different tension levels on is y= 0.4664x + 6.411, for thread3 is y=
seam extensibility 0.1837x + 5.8899 and for thread4 is y=
(As shown in table8, fig.5) it can be noticed 0.3134x + 4.5232. Where y= seam
that thread4 gives the smallest seam extensibility & x= thread tension level. The
extensibility that can be attributed to its thread type correlation coefficient on seam
filament construction, while spun extensibility is positive but its significant
construction is more extensible than filament effect in general is very strong, as the
construction. correlation is strong when the value of R
Despite thread1 and2 have the same size, nearest to 1. For thread1 R= 0.8013, for
thread1 gives higher seam extensibility which thread2 R= 0.9611, for thread3 R= 0.8786
can be attributed to fiber type as polyester and for thread4 R= 0.9598.
elongate more than cotton. 3.1.5. Effect of thread type at different tension
Whereas thread1 and3 have the same fiber levels on seam pucker
type and construction, thread1 gives higher Table9 illustrates the effect of thread type at
seam extensibility that can be referred to different tension levels on seam pucker
thread number, as thinner thread is more Note: Seam pucker evaluated according to
extensible. AATCC where 5 means no pucker and
Results detect that, there is a direct 1 means severely pucker

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Table 9 Effect of thread type at different tension levels on seam pucker

Seam pucker (level)
Thread
tension level Thread 1 Thread 2 Thread 3 Thread 4
1 4.4 3.8 3.2 2.8
2 4.6 4.4 3.8 3.4
3 4.8 4.6 4.4 3.8
4 3.6 3.4 3 2.4
5 3.4 3 2.8 2.2

Effect of thread type at different pucker.

tension levels on seam pucker Seam pucker decreases by decreasing thread
tension in case tension level1, 2 and3, while
Seam pucker

5 tension4 and5 differed as seam pucker

4 increased by decreasing thread tension. This
(level)

3 Thread 1 can be referred to the gathered bobbin thread

2 Thread 2 behind fabric which increased pucker.
1
Thread 3 The thread type regression equation for
0
thread1 is y = -0.3x + 5.06, for thread2 is y =
Thread 4
-0.26x + 4.62, for thread3 is y = -0.16x +
Thread tension level 3.92 and for thread4 is y = -0.22x + 3.58.
Where y= seam pucker & x= thread tension
Fig.6. Effect of thread type at different tension levels on level. The thread type correlation coefficient
seam pucker
on seam pucker is negative but its significant
(As shown in table9, fig.6) it can be noticed effect in general is weak, as the correlation is
that thread4 gives the highest seam pucker strong when the value of R nearest to 1. For
that can be attributed to its filament thread1 R = 0.5799, for thread2 R =
construction, while spun construction puckers 0.3772, for thread3 R = 0.1495 and for
less than filament construction. thread4 R = 0.2677.
Despite thread1 and2 have the same size, 3.1.6. Effect of thread type at different tension
thread1 gives lower seam pucker which can levels on seam appearance
be attributed to fiber type as polyester Table10 illustrates the effect of thread type at
puckers less than cotton. different tension levels on seam appearance
Whereas thread1 and3 have the same fiber Note: Appearance evaluated (from2 to10) where
type and construction, thread1 gives lower 10 means best appearance and 2 means worst
seam pucker that can be referred to thread appearance.
number, as thinner thread makes fewer
Table 10 Effect of thread type at different tension levels on seam appearance
Seam appearance (level)
Thread Thread 1 Thread 2 Thread 3 Thread 4
tension level
1 8.8 7.6 6.4 4.8
2 9.2 8.8 6.8 5.2
3 9.6 9.2 7.2 5.6
4 7.2 6.8 6 4
5 6.4 6 5.6 3.2

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Effect of thread type at different intermediate, as the correlation is strong

tension levels on seam appearance when the value of R nearest to 1. For thread1
R = 0.6123, for thread2 R = 0.3772, for
Seam appearance

10 thread3 R = 0.36 and for thread4 R =

8 0.5216.
6 Thread 1
(level)

4 Thread 2
4. Conclusions
2 Thread and tension control are very
0 Thread 3 important elements in apparel manufacturing

Thread 4 process.
Thread tension level Sewing thread which is described by fiber
type, construction, and size, has a significant
Fig.7. Effect of thread type at different tension levels on effect on seam properties.
seam appearance
Thread 1 gives best result, due to its small
There is an inverse relation between seam size as well as its polyester fiber type in
appearance and seam pucker as seam addition to its spun construction. So the
appearance increases when seam pucker authors recommend using it for its best sew
decreases. ability.
(As shown in table10, fig.7) it can be noticed Thread tension has a significant effect on
that thread4 gives the lowest seam seam properties.
appearance that can be attributed to its high Tightened thread tension causes seam pucker
pucker resulted from its filament that raises seam thickness which effect
construction, while spun construction gives inversely on aesthetic appeal.
lower pucker thus better aesthetic appeal. By loosen the thread tension fabric during
Despite thread1 and2 have the same size, sewing became uncontrolled and bobbin
thread1 gives higher seam appearance which thread was gathered behind fabric that leads
can be attributed to fiber type as polyester to worst seam properties.
puckers less than cotton therefore appears The authors recommend using the middle
better. tension (tension control 3) that gives the best
Whereas thread1 and3 have the same fiber seam properties.
type and construction, thread1 gives better 5. References
seam appearance that can be referred to 1- Garment Making, Sewing Thread &
thread number, as thinner thread makes fewer Selection Criteria, New Cloth Market
pucker thus better appearance. Magazine, Thursday, August 22, 2013.
Seam appearance increases by decreasing 2- Shaeffer, Claire, Sewing for the industry,
thread tension in case tension level1, 2 and3, 2nd, Preason, 2013.
while tension4 and5 differed as seam 3- Ukponmwan, J.O., Mukhopadhyay, A. and
appearance decreased by decreasing thread Chatterjee, K.N., Sewing threads, Textile
tension. This can be referred to the gathered Progress, The Textile Institute, Vol. 30,
bobbin thread behind fabric in addition to 2000.
open stitches occurred which decreased 4- Hearle J. W. S., High-Performance Fibers,
appearance. Woodhead Publishing, Ltd., Cambridge,
The thread type regression equation for England, 2001.
thread1 is y = -0.68x + 10.28 , for thread2 is 5- Carr, H.,& Latham B., The technology of
y = -0.52x + 9.24, for thread3 is y = -0.24x + clothing manufacturing, 3rd, ed. BSP.
7.12 and for thread4 is y = -0.44x + 5.88. Professional books, London, 2000.
Where y= seam appearance & x= thread 6- Eberle, H., Hornberger, M., Menzer, D.,
tension level. The thread type correlation Hermeling. Clothing technology from fiber
coefficient on seam appearance is negative to fashion, 3rd ed., Verlag Europa-
but its significant effect in general is Lehrmittel, 2002.
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International Design Journal Volume 4 Issue 3 Technical Issues

7- Rudolf, A., Gersak, J., Influence of twist on sewing thread at different sewing stages,
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Textile Research Journal, 2006. 11- Marjorie M. Baker, M.S., Extension
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Fabrics, Volume 3, Issue 4 2008. of thickness.
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