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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.