Chapter 05: Looming
Loom
A loom is a device used to weave
cloth. The basic purpose of any
loom is to hold the warp threads
under tension to facilitate the
interweaving of the weft threads.
A loom can not be said a machine
but it is a device which is used to
produce woven fabric.
The ma in function of the loom is
to weave clothes. For enhancing
the working capabilities, the size
and shape of the looms may vary
but the basic structure of all types
of looms are same.
Important Parts of Loom:
1. Heald/Heddle: Wire or cords with eyelets that hold warp yarns in a place. It holds the warp
yarns in a place. It also helps in shed formation. It is used for determining the warp thread
density in a fabric.
2. Heald shaft/Harness: A wood or metal frame that holds the heald/heddles in position in the
loom during weaving. It is usually more than one.
3. Shuttle/Filling Carrier: This is a vehicle for weft & passes through the divided warp for the
interlacement of the warp & weft.
4. Shuttle box: Compartment of each end of the sley of a shuttle loom used to retain the shuttle
between picking motion.
5. Picker: It is a piece of leather or other metal placed in grooves or on a spindle inside a shuttle
box.
6. Beams: A cylindrical body with end flanges on which a multiple of warp ends is wound in
such way to permit the removal of these yarns as a warp sheet.
7. Front rest: It is a fixed roller placed in front of the loom above the cloth beam & act as a guide
for the cloth to wind on to the cloth beam.
8. Lease rods: The division of warp yarn into one & one, two & two, & so on is termed as lease.
The two rods passed between the two successive divisions of warp yarns are called lease rods.
9. Slay: It is the portion of loom that carries the reed and oscillates between the harness & the
fell of the cloth.
10. Reed: A comb like wire or device used to separate yarns on a loom & to beat up the filling
during weaving.
11. Treadle: The treadle is a paddle or lever under a loom with which a thread is connected by
means of cords.
12. Temple: Roller device on a loom that hold the cloth at a proper width to prevent it from being
drawn in too much by the filling.
Some Important Terminologies
Drawing-in: Drawing-in is the entering of
yarns from a new warp into the weaving
elements of a weaving machine, namely drop
wires, heddles and reed, when starting up a
new fabric style. So, drawing-in consists of
threading the warp yarns through the drop
wires, the healds and the reed. A drop wire is
a narrow metal sheet that that is hung in the air
by the tensioned warp yarn.
(Today, the drawing-in and tying-in processes are fully automated. Drawing-in is done using
robot-like machines. A special type of heddle is needed for automated drawing-in. The warp ends,
taken from the warp sheet, are fed individually to the drawing in element; heddles are separated
from the stack and brought to the drawing-in position; a plastic knife opens a gap in the reed and
a hook draws-in the warp end through the heddle and reed in one step.)
Reed spaces: A reed space is the opening between two dents (metal) in a reed. After drop wire,
the warp yarn goes through the heddle eye (there is only one warp yarn per heddle eye). Then the
yarn is threaded through the reed spaces. In general, one, two or three warp yarns are passed one
reed space.
Tying-in/ knotting: The process of tying up the new warp
yarns of full beam with the corresponded old weaver’s
beam. (Hand knotting/Automatic knotting).
Drafting and drafting plan: The process of drawing
the warp yarn through the eye of heald frames
according to design is called drafting, and the plan
which indicates how drafting needs to be done is called
drafting plan. It also denotes the number of heald shaft
required for a given weave repeat.
Denting and denting Plan: The process of inserting
warp threads or ends through the dents of reed is called
denting and the plan that indicate the order in which
denting is done is called denting plan. Usually two
yarns are passed through each dent.
Looming
The process of preparing a loom before starting the weaving process is commonly known as
looming. It includes drawing in draft, denting, pinning, gaiting and knotting of warp threads by
using different looming elements.
Looming process
Drawing-in draft
Passing warp threads from sized beam through heald eye of heald frame.
(Manual DID /Automatic DID)
Denting
passing of warp threads through the dents of a reed by maintaining required warp density
is known as denting. (Manual Denting / Automatic denting)
Pinning
The process of passing warp threads through drop wires is called pinning.
(Open drop wire/Close drop wire.)
Gaiting
Loading the heald frames, reed, drop wires and weavers beam into the loom after
completing the drawing, denting and pinning to facilitate the next process is known as
gaiting.
Tying-in/ Knotting
Process of tying up the new warp yarns of full beam with the corresponded old
weaver’s beam. (Hand knotting/Automatic knotting).
Reed count:
Reed count refers to the number of dents, or spaces, per inch on a reed. This system is extensively
used in the weaving industry.
Some systems of reed count:
Name of System Basis Of numbering
Stockport Number Of dents per 2 inches
Radcliff Number Of dents per 1 inch.
Bradford 20 dents per 36 inches.
Functions of Reed:
• Reed pushes the lastly laid pick of weft to the cloth fell.
• It determines the fineness of the cloth in conjunction with the heddles.
• Reed acts as a guide to the shuttle which passes from one end of the loom to the other.
• It helps to maintain the position of the warp threads.
• Reed determines the openness or closeness of the fabric.
Roles of Heald frame:
• To support and guide the heddles and warp yarns in a stable and smooth manner.
• To create different patterns of warp yarn shedding by changing the order and timing of the
Heald frame movement.
• To cooperate with other parts of the weaving loom, such as the reed, the shuttle, the rapier,
or the air jet.
• To ensure the quality and efficiency of the weaving process by having good mechanical
performance, accurate dimension, and firm structure.
