Knitwear TechnologyKnitwear TechnologyPart Two : Multi-jack, jacquard Part Two : Multi-jack, jacquard

steel selectionsteel selectionJimmy LamJimmy Lam

Institute of Textiles & ClothingInstitute of Textiles & Clothing

Learning ObjectivesLearning Objectives

Multi-step jack selectionMulti-step jack selection Pattern drum selectionPattern drum selection Jacquard steel selectionJacquard steel selection

Multi-step jacks selectionMulti-step jacks selection

The earlier selection based on simple needle The earlier selection based on simple needle and jack (high/low butt) principle can only and jack (high/low butt) principle can only produce a very small pattern size.produce a very small pattern size.

To expand pattern, we have to put more To expand pattern, we have to put more jacks under needles.jacks under needles.

Multi-step jacks selection (with 6 to 8 jacks) Multi-step jacks selection (with 6 to 8 jacks) is an example. (Universal MC-410)is an example. (Universal MC-410)

Multi-step jacks selectionMulti-step jacks selection

More jacks are put under the needles to increase the pattern size

Example of multi-step jack patternExample of multi-step jack pattern

Knitting SequenceKnitting Sequence

Summary of patternSummary of pattern

No pattern costs, pattern jacks are set manuallyNo pattern costs, pattern jacks are set manually Pattern jack setout cannot be saved, re-Pattern jack setout cannot be saved, re-

arrangement is needed for new patternarrangement is needed for new pattern Pattern time is jack set out timePattern time is jack set out time Pattern width is narrow;Pattern width is narrow; Pattern height depends on number of control Pattern height depends on number of control

card used.card used.

Pattern Drum SelectionPattern Drum Selection

So far, we have discussed pattern (jacquard) So far, we have discussed pattern (jacquard) selection by: selection by: – Hi/lo butt needles;Hi/lo butt needles;– Hi/lo butt jacks and needles; and Hi/lo butt jacks and needles; and – Multi-step jack selectionMulti-step jack selection

To increase pattern size, we can useTo increase pattern size, we can use– Pattern drum ;andPattern drum ;and– Pattern steel selectionPattern steel selection

Pattern Drum and JacksPattern Drum and Jacks

Universal MC-M is the only machine offers Universal MC-M is the only machine offers pattern drum selectionpattern drum selection

The machine has two pattern drums, each drum The machine has two pattern drums, each drum has 72 pattern keys and each key has 36 toothhas 72 pattern keys and each key has 36 tooth

The pattern height is 144 (2X72) courses and The pattern height is 144 (2X72) courses and the pattern width is 36 wales (jacks are in the pattern width is 36 wales (jacks are in diagional set out)diagional set out)

PrinciplePrinciple

The drum will be lift up and give forward and The drum will be lift up and give forward and backward racking for new selection when the carriage backward racking for new selection when the carriage reaches the right or left end of the needle bedreaches the right or left end of the needle bed

If “teeth” remains in the pattern key, it will push the If “teeth” remains in the pattern key, it will push the pattern jack to “sunk” below the needle bed, results in pattern jack to “sunk” below the needle bed, results in miss loop.miss loop.

Only when jack in upward position, the jack butt can Only when jack in upward position, the jack butt can select by needle bed for knitting action. select by needle bed for knitting action.

Techno-economics of pattern drum Techno-economics of pattern drum selectionselection

We concern with pattern preparation time and pattern We concern with pattern preparation time and pattern costcost

Pattern Drum SelectionPattern Drum Selection– Pattern size 144 courses X 36 walesPattern size 144 courses X 36 wales– Cost of 144 courses gives 144 pattern keysCost of 144 courses gives 144 pattern keys– If each key is @5.00, total cost is 144X5=$720If each key is @5.00, total cost is 144X5=$720

Pattern timePattern time– One pattern key takes 25 secondsOne pattern key takes 25 seconds– 144 pattern keys take 25 sec X 144 = 1 hour144 pattern keys take 25 sec X 144 = 1 hour

If produce by jacquard steel selectionIf produce by jacquard steel selection Pattern cost is equal to labour costPattern cost is equal to labour cost Pattern time Pattern time

– One jacquard steel takes 20 min, a 144 jacquard steels take One jacquard steel takes 20 min, a 144 jacquard steels take 48 hours48 hours

– About 6 days wages, roughly $1500-2000About 6 days wages, roughly $1500-2000 Therefore, for small pattern, pattern drum uses one Therefore, for small pattern, pattern drum uses one

hour and half the money on jacquard steel. In addition, hour and half the money on jacquard steel. In addition, storage of pattern drum/keys are lot easystorage of pattern drum/keys are lot easy

Jacquard Steel SelectionJacquard Steel Selection

Jacquard Steel SelectionJacquard Steel Selection

It is the only mechanical jacquard selection It is the only mechanical jacquard selection allows unlimited or freehand design.allows unlimited or freehand design.

Pattern width = needle bed width (roughly 80 Pattern width = needle bed width (roughly 80 inches)inches)

Pattern height = No. of jacquard steelsPattern height = No. of jacquard steels

Jacquard Steel SelectionJacquard Steel SelectionSingle systemSingle system

Jacquard Steel selectionJacquard Steel selectionDouble systemsDouble systems

Patterning on Jacquard SteelPatterning on Jacquard Steel

Example : Four colour pattern on Example : Four colour pattern on jacquard steeljacquard steel

Jacquard Steel (single system)Jacquard Steel (single system)

Hole in the steel = needle missHole in the steel = needle miss No hole/bolcked= needle selectedNo hole/bolcked= needle selected For a 3 colour rib jacquard pattern with 30 For a 3 colour rib jacquard pattern with 30

surface courses on single jersey, it will take 90 surface courses on single jersey, it will take 90 jacquard steelsjacquard steels

Jacquard Steel (Double System)Jacquard Steel (Double System)

Requirement : Two rows of holes on jacquard steel, Requirement : Two rows of holes on jacquard steel, one for each knitting system;one for each knitting system;

Three cam tracks for each knitting system, one for the Three cam tracks for each knitting system, one for the needle, and two for the jacksneedle, and two for the jacks

The jacquard steel selection is done when the cam The jacquard steel selection is done when the cam carriage is away from the needle bed.carriage is away from the needle bed.

The time available is only a fraction of second, The time available is only a fraction of second, therefore, vibration from the heavily jacquard roller therefore, vibration from the heavily jacquard roller and steel could cause a wrong pattern on fabric.and steel could cause a wrong pattern on fabric.

DiscussionDiscussion

Discuss the advantages of pattern drum Discuss the advantages of pattern drum selectionselection

Discuss the advantages and limitation of Discuss the advantages and limitation of jacquard steel selectionjacquard steel selection