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Magic of Weaving : TARA Loom
It
is the creative urge of the humankind that has brought civilisation
to its present level. The hallmark of excellence of our ancient
civilizations is often found in the artifacts of the period in the
items of daily use - utensils, implements, and fabric. The oriental
civilizations have a history of nearly four to five millennia in
creation of fabrics. Silk and spices formed the core of Euro-Asian
trade and their quest led to the discovery of whole new continents -
the Americas and also to colonialism. This story is not a happy one.
However, communities that survived could remain self-supporting for
their clothing. They produced the raw material - wool, cotton or
silk and continued to "weave" their fabric from which they created
their garments.
India has one of the richest traditions in this
creative activity - from Kashmir to Kanyakumari, Kachch to Kohima.
The weaving device - the loom has been subject to constant hostile
threats of being extinguished by highly mechanised, organised
machinery-dominated textile industry for over a century and in
recent decades, by the advent of the powerloom. If the handloom has
survived, it is because of its highly elastic range of adaptation in
meeting communities’ needs and in its ability to produce exquisite
fabrics which mills cannot produce with all their sophisticated
technologies.
The textile sector, after agriculture, employs
the largest work force. There are nearly 3.5 million looms in India.
Over ten million people work with these looms to earn their
livelihood - another fifteen million depend indirectly on the
handloom weavers for their livelihood. Handlooms fill a very
important economic niche. They also account for more than 20% of the
total fabric produced in the country.
Existing Technologies
There are around 3.5 million machines ranging
from loin looms to pit looms and frame looms in India. The features
of the looms are:
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Most of the looms
are locally manufactured and lack the detailed engineering and
hardware needed to weave good quality fabrics. |
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Upgrading of
handlooms by incorporating only a ‘take-up’, has resulted in
some increase in productivity but without any improvement in the
quality of cloth. In fact, the non-uniformity in pick spacing
due to this often becomes more obvious after the finishing
processes. |
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Incorporating new
mechanisms (take-up, fly wheel and let off) on existing
handlooms is cumbersome and an expensive process. |
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In the standard
five-wheel take-up mechanism adapted from the power loom, the
gears have to be changed whenever the pick spacing is changed.
This means that a weaver has to maintain a large inventory of
gears and a great deal of time and effort go into changing them
and making other minor adjustments. This has been the major
reason for most weavers not accepting this mechanism. |
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Fully automatic and
semiautomatic looms are not popular with weavers because of the: |
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- very high effort required for operation
- limited design capability
- very high capital cost |
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Most of the
handlooms cannot produce synthetic fabrics of acceptable quality
and at viable production rates. |
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Almost all
traditional frame looms are made out of wood which is:
- increasingly scare and expensive
- difficult to manufacture
- not rigid - so they vibrate during the
weaving process
- cumbersome, heavy and difficult to
transport
- take up a lot of vertical space and floor
area
- prone to wear and tear |
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Based on these
observations, it was concluded that R & D efforts must: |
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Be more systemic |
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Be more closely
linked with the processes of production and marketing and
incorporate the opportunities and constraints of how the
technologies will actually be manufactured, sold, maintained and
used |
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Be based on genuine
market research, both regarding the needs of the weaver and the
end client |
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Establish standards
for equipment and ancillaries, particularly to facilitate
introduction of subsequent improvements in this technology |
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Fully understand the
overall impact of modification (such as by using components from
power looms) on the performance of the machines |
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Focus on the
complete technology configuration rather than trying fruitlessly
to upgrade existing ones by incorporating accessories |
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Undertake detailed
surveys to identify precise technology needs |
This methodology requires a detailed analysis of
each and every component of the looms and the weavers capacity and
constraints.
Design criteria for the TARA Loom
To meet the identified objectives of
intervention, the following design criteria were established:
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A. |
High productivity |
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reduce the cost of unit output of the machine |
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increase income of the weaver
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B. |
Superior quality |
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easy consumer acceptability
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C. |
Ease of operation |
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increase overall efficiency of the machine |
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easier pick spacing adjustment |
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weave long length of fabrics and thus save on doffing time |
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weaving operation confirms with the existing traditional skills
of the weavers
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D.
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Versatility |
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weave hand spun as well as mill spun yarn |
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suitable for cotton, wool, silk and synthetic |
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operate at high speed even with six treadles and four shuttles |
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weave a variety of products
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E.
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Ease of maintenance |
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oiling required only once in a while
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F.
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Low Cost |
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within purchasing power of the weaver through various government
schemes
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G.
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Compactness |
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should fit easily inside the weavers’ hut |
Results
Working within this framework, the TARA loom was
designed at Development Alternatives by a team of textile and
mechanical engineers, traditional weavers, sociologist, economist,
market specialist, ergonomic expert and product designer. The TARA
Loom has the following features:
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1. |
New take-up mechanisms |
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- can weave fine
fabrics of 90 picks per inch to coarse fabrics of 14 picks per
inch without changing any gear. Pick spacing can be adjusted by
simply shifting the position of the shield plate covering the
ratchet by loosening a bolt |
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- it is an integral
unit requiring no special fixture |
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- it requires less
effort because of low friction |
All this was
possible by redesigning the dimensions of the gears and ratchets
to achieve a reduction of sufficient magnitude which could thus
cover such a wide range of pick spacing. The throw of the
driving pawl was enhanced by connecting it to the shuttle box
through appropriate linkages.
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2.
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Fly-Wheel |
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- enables jerk free
weaving |
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- sustains high
speed weaving |
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- fixes the throw of
the beater |
This was possible by
redesigning the flywheel to have just the right moment of
inertia and eccentricity ratio. The same flywheel can be used
for looms of reed space 40" to 78" simply by readjusting the
position of the crank. Moreover, the flywheel shaft is also
mounted on ball bearing.
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3.
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Negative Let-off Mechanism |
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- to ensure uniform
let-off |
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- even warp tension |
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To achieve this a
special ruffle was designed to provide uniformly distributed
friction on the warp beam which made it possible to release the
yarn by the same amount in every cycle instead of a jerky let
off as in other looms. |
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4. |
Improved Frame |
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- to ensure adequate
support and rigidity to reduce vibration |
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- ease of assembly
and transportation |
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- low cost
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- longer durability |
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- compact and
modular |
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For this, rolled MS
angles are used in the structure of the frame such that there is
no vibration. This makes it possible to weave better quality
fabric. The frame has been designed to take up less floor area
and height. It can thus be fitted easily inside huts, especially
in the hills which have very low ceilings. The length of the
loom is also less, so that the weavers can fix the broken ends
of yarns from the seat itself. With just two sets of spanners a
complete loom can be assembled. This makes it possible to set up
around 10 to 13 machines in 8 hours. |
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5.
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Emery and Cloth Roller |
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These rollers are
carefully positioned in the loom so that: |
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- it does not hit
the weaver’s knee during weaving |
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- it can accommodate
longer length of cloth on the roller (around 100 mts. of fabric
for 2/40s warp and 20s weft with pick spacing of 44 per inch.) |
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6.
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Smooth Surface Back Rest and Lease Rods |
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- ensure smooth
friction-free movement of the yarn |
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- improve the
quality of the fabric |
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- ensure proper
working of the let-off mechanism |
Chrome plated pipe is used for the back rest and
smooth metal sheet it fitted on wooden rods for the lease rod.
7. The Beater
Since traditional technologies are time-tested,
they have certain levels of perfection. The beater is a very good
example of this, and the TARA loom uses the traditional beater
design and material.
Dissemination of TARALoom
The TARAloom has found widespread acceptance
among the weavers. Its productivity has been validated and is found
to be at least 35% higher than any other loom. Development
Alternatives has demonstrated that it is possible to combine high
productivity, superior quality of fabric and ease of operation in
one machine that can also use different yarns - cotton, wool, silk
and synthetic. A traditional weaver can learn to operate this
machine in less than two hours making the transition to the improved
loom at no extra cost in terms of time and money. No wonder the
TARAloom is in operation in almost all the states of India.
Acknowledgment
the development of TARALoom was supported by
Department of Science Technology, and Swiss Agency for Development &
Cooperation.
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