The Hole Problem in Knit Goods
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Transcript of The Hole Problem in Knit Goods
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The Hole Problemin Knit Goods
Three Basic Considerations whenKnitting a Fabric to Reduce Holesand Dropped Stitches
Yarn
Machine
Housekeeping and maintenance
The Relationship to Yarn
Cause and effect of:
Holes
Dropped stitches
Unwanted tucks
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Holes and Other Alias
Hole
A fabric imperfection in which oneyarn or several yarns aresufficiently damaged to create anopening.
Fairchilds Dictionary of Textiles
Single Jersey - Face
Hole
Holes and Other Alias
Dropped Stitch
Defect in knitted fabric; recurrentopenings in one or more wales of aknitted fabric because the stitches didnot knit. Not to be confused with ahole, caused by rupture of one or moreyarns.
Fairchilds Dictionary of Textiles
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Dropped Stitch
Single Jersey - Face
Single Jersey - Face
Dropped Stitch
Holes and Other Alias
Unwanted Tuck
An unwanted knitting stitch that
produces tuck or open work effects by
having certain needles hold more than
one stitch at a time.
Fairchilds Dictionary of Textiles
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Single Jersey - Face
Unwanted Tuck Stitch
Unwanted Tuck Stitch
Single Jersey - Back
Unwanted Tuck Stitch
Single Jersey - Face
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Unwanted Tuck Stitch
Single Jersey - Back
Types of Loops
Regular Knit LoopTechnical Face
Regular Knit LoopTechnical Back
Types of Loops
Tuck LoopTechnical Face
Tuck LoopTechnical Back
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Yarn
Size
Variation (thick and thin)Strength
Twist
Knots and splicing
Hairiness
Trash content
Incorrect Yarn Size
If yarn size is too large for the
machine gauge or the needle
hook, then stresses on the yarn
and fabric during knitting can
result in holes.
NCSU OptimumYarn Formula
Single Knit: Cut2
18
Double Knit: Cut2
15
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Thick and Thin Yarns
Variation in yarn diameter can
result in variations in yarn tensions
resulting in holes and drop stitches.
Hole
Long Slub Single Jersey
Hole
Long Slub Single Jersey
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Yarn Strength
If yarn strength is too low for
the knitting parameters being
used (tightness factor, stitch
length, etc.), holes can result.
Tightness Factor for Knits
TF = 9.567____
St. Length x NE
sinkeror
trick wall
needle
cam angle
Tension in Knitting and Robbing-Back
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Yarn Twist
If yarn twist is too high, twist
liveliness can result causing the
yarn to kink. This changes the
yarn diameter and yarn tension,
which can result in holes or drop
stitches.
Twist Multiple
TM = TURNS PER INCH
NE
KNITTING TWIST = 3.5 TM
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Yarn Knots orUnsatisfactory Splicing
Incorrect yarn splicing or knot
tying can cause high and variableyarn tension, which results in
holes and drop stitches. Also,
long tails from knots result in
doubling or tripling of the yarn
diameter.
Yarn Knot and Tail Single Jersey
Hole
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Yarn Knot and Tail Single Jersey
Hole
Knot and Tail Single Jersey
Hole
Yarn Hairiness
A yarn with excessive hairiness
can increase yarn tension and lint
shedding, which can result in
holes and drop stitches.
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Coefficient of Friction
UNWAXED .24
WAXED [ APPAREL ]= .14 to .15
Yarn Trash Content
Yarns with high levels of trash
can create problems with
tightness stress, weak spots in
yarn, and variations in yarn
tension.
Hole
Trash Single Jersey
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Hole
Trash Single Jersey - Back
Hole
Trash in Yarn
Conclusion
Yarn quality can directly
affect fabric quality.