Research Initiatives
Weaves and Knits
a. Weaving
² Millions
of miles of fabric are needed every year to meet consumer demand – the industrial
loom makes it possible
² Basic
materials needed for weaving are two sets of threads where first set is weft,
and second set is the warp
² Warps
are threaded through eyes
² The
read then pushes the threads together
² Pedals
provide control on the machine
² Shaft
raises so the pedals go up and the thread is moved with them
² A
few hundred pedals and two shafts moving up and down together are required to
create simple patterns
² Speed
of the machine comes from the loom and its need to move the weft through the
warp as fast as possible
² Two
challenges of the modern loom, how to weave thread quickly without a shuttle
and how to minimize thread removing
² Two
rapiers that “exchange” thread as they meet in the middle
² Patterns
are created through the set-up of thread on the track with a weft presenter to
select different colors as the machine works; each strand has its own control
system; a jacquard loom helps with more colors for a more complicated pattern
(holds more strands of thread)
² Threading
of a jacquard loom is so time-consuming that it is done just once
b.
Twill Weaving
² twill
fabric is characterized by diagonal lines on the face of the cloth, formed by
the rising or floating of warp yarn over the filling yarns
² twill
line determines the direction of the diagonal (right hand twill = z-twill; eft
hand twill = s-twill)
² twill
lines can be anywhere from 15-75 degrees
² 45
degrees is normal, anything higher is a steep twill
² Counter
of a twill designates the order of weaving of the first hand of the repeat
² 1
by 2 = warp faced twill; 2 by 1 = filling faced twill
c.
Jacquard
² Plain
weave
² Patterned
weave
² Before
1800, patterns were picked out by hand until 1801 when joseph jacquard invented
a revolutionary new loom attachment that automated how patterns were woven
² Automation
enabled through the loom made complex designs cheaper to produce, so intricate
patterns became available to more people
d.
Knits – Weft and Warp Knitting
² Weft
knitting is done when loops are formed in a horizontal manner by adjacent
needles
² Warp
knitting is accomplished by forming loops in a vertical direction; intermeshed
vertically with two whales
e.
Fire Identification by Burning
² Cotton
(natural cellulosic fiber) – burns, doesn’t melt; smells like burning paper or
wood; residue is gray ash
² Flax
(natural cellulosic fiber) – burns, doesn’t melt; smells like burning paper or
wood; residue is fine gray ash
² Wool
(natural protein fiber) – burns, doesn’t melt; strongly smells of burning hair or
feathers; stops burning when removed from fire; residue is black hollow bead
that can be crushed to black powder
² Silk
(natural protein fiber) – burns, doesn’t melt; smells of burning hair or
feathers (odor is not as strong as wool, silk doesn’t contain sulphur); stops
burning when removed from fire; residue is black hollow bead that can be
crushed to black powder
² Rayon
(artificial cellulosic fiber) – burns, doesn’t melt; smells like burning paper
or wood; residue is fine gray ash
² Polyester
(artificial fiber) – shrinks from heat, melts, burns, can drip; smells chemical,
sweet; residue is hard cream or black colored bead that cannot be crushed
² Nylon
(artificial fiber) – shrinks from heat, melts, can burn; smells a bit like
celery; residue is hard cream or black colored bead that cannot be crushed
² Acrylic
(artificial fiber) – shrinks from heat, melts, and burns; sputters when
burning; acrid smell; residue is hard black bead that can be partially crushed
² Acetate
(artificial fiber) – shrinks from heat, melts, and burns; smells like burning
cellulosic fibers (of burned wood, paper) with a bit of vinegar; residue is
hard black bead that cam be partially crushed
f.
Testing
² Tensile
strength test – determines the strength and the elongation of a strip of fabric;
when the fabric breaks, the test is stopped; force is measured in kilograms and
extension/stretch is measured in millimeters
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