Interlacing yarns to make fabrics
• Fabric: a woven, knitted, plaited, braided, or felt material such as cloth, lace,
• A planar structure consisting of yarns or fibers.
Starting Materials for Fabrication
• Solutions: films and foams
• Fibers: felt and fiberwebs or nonwovens
• Composite: fabrics combined together (bonded, laminated, quilted); fabrics
combined with solutions, fibers, and yarns.
• Most widely used method with many possibilities.
• Fabrics unravel and fray and have grain.
• Same weave fabrics may vary by yarn size or twist, fiber, count, color, design,
• Used in apparel, furnishings, and industrial products.
Three Principle Ways of Manufacturing Fabrics (Fabrication)
• Woven fabrics
o Woven fabrics: two sets of yarns (warp and filling) are interlaced at
o Woven fabrics are fabrics constructed by interlacing two sets of yarns
at right angles to one another, in a predetermined pattern.
• Knit Fabrics
o Yarns are interloped.
➢ Fiber bonding:
o Non-woven fabrics
• There are a large number of minor fabrication methods.
➢ Examples: braids, lace, films, foams, felt, leather, and fur
➢ Two sets of yarns (warp and filling)
➢ Firm and rigid due to right-angle positions of yarns
➢ Yarns are interloped Woven Fabric Composition
• Warp ends: the yarns that run the length of the loom.
➢ Yarns running lengthwise in woven fabrics are called warp yarns or ends.
• Filling or welt (picks)
• Interlaced different ways to make patterns
• Interlacing: the point at which a yarn changes its position from one side of
the fabric to the other.
• Float: yarn crosses over more than one yarn at a time.
• The thread count of a woven fabric is the sum of the number of ends per inch
and the number of picks per inch. Fabric counts range from a low of 8 to well
➢ 80x80, 52x48, 42x36 Balanced
➢ 120x80, 108x64, 92x52 Unbalanced
• Looms are capable of producing woven fabrics with structures that range
from the simplest to the most complex, when proper loom attachments are in
• Warp beam: warp yarns wound around a large cylinder
• Warp: lengthwise yarns threaded through loom.
• Harness: frame that hold heddles and controls basic weave.
• Heddle: wires through which warp is threaded; controls basic weaves.
• Shed: space created by warp when some harnesses rise and other lower.
• Reed or batten: device pushes filling yarns in place.
• Dent: space in reed through which warp is threaded
• Filling yarn insertion device: related to loom type, shuttle, rapier, gripper,
or jet, it carries filling through shed.
• Filling: yarns interlaced with warp to create fabric cloth.
The Weaving Process
• If a 45” wide fabric having 80 epi is to be woven, the warp beam must contain
45 x 80 = 3600 ends of warp yarn. These 3,600 ends must be kept in order,
parallel to each other and uncrossed.
• After the beam is assembled, it is slashed (omitted for filament yarns); i.e.
each yarn is coated, full length, with a size usually consisting of a rice or
potato starch. After drying, the beam is ready for use.
• When the shuttle has traversed the loom leaving a filling yarn in the shed, a
reed swings forward and beats the filling yarn into the v where the shed
opens from the previously formed cloth (beating up)
• The harness, which were raised and then lowered, and the steps are repeated
in order: shedding, beating, picking, beating. Weaving Motion
• Picking, fill insertion
• Letting-off; take-up, warp control
Types of Looms
• Single shed loom
➢ Loom with shuttles
o Hand looms
o Power-operated looms
➢ Shuttleless loom
o Projectile looms; Missile loom or Gripper loom
o Rapier looms
o Air-jet looms
o Water-jet looms
• Multiple shed loom; multi-phase loom
➢ Parallel shed machines
➢ Circular looms; wave-shed looms
➢ Triaxial looms
Shuttle vs. Shuttleless
• Shuttle looms typically average about 130 picks per minute (ppm) and fabric
production rates are typically in the 1.5 to 3.0 inches per minute (2.5 to 5.0
yards per hour). Mills having 1,000 or more looms under one roof are
• Modern shuttleless looms weave fabric at a much faster rate than shuttle
• The guiding principle behind the development of shuttleless looms is that is
makes little sense, economically or energetically, to transport a shuttle
weighing one pound across the full width of a loom in order to deposit a
length of yarn weighing around 0.0007 ounces in a fabric. To eliminate the
shuttle, other means of pick insertion needed to be found.
• Inspection of the selvage of a woven fabric shows whether a shuttle or
shuttleless loom wa