Juki LK-280 User Manual

mJUICI

m

HIGH

SPEED,

SINGLE

NEEDLE,

ENGINEERING

LOCKSTITCH

INDUSTRIAL

SEWING

MANUAL

I •

Gl

H • UUKI

BARTACKING

MACHINE

TOKYO

JUKI

INDOSTRIAl

CO..

LTD

•A

MODEL

LK-280

CONTENTS

ENGINEERS

MANUAL

(STANDARD

(CORRECTIVE

(I)

(II)Thread

ADJUSTING

Thread

MEASURES

slippage

breakage

(III)Inadequate

(IV)

Needle

( V

)Cautions

(VI)

Inadequate

(CAUTIONS

(HOWTOTIGHTEN

(ADJUSTING

(I)

Adjusting

(II)

Adjusting

(III)

(IV)

Adjusting Adjusting

breakage

ON

DISMANTLING

METHODOFVARIOUS

FIGURES) 1

FOR

thread

on sewing

thread

THE

RATTLE)

the

starting

the

pedal

the

thread

the

position

FAULTY

STITCHES)

trimming

synthetic

tension

OF PARTS) 22

DEVICES)

and

pressure

trimming

of

materials

stopping

decreasing

device

the

stop-motion

with

unit

synthetic

lever

thread

7 '

7

11

16

18

19

20

23

24

34 39 42

(V)

Adjusting

(VI)

Adjusting

(VII)

(VIII)

(IX)

(X)

(XI)

Adjusting Adjusting Adjusting Adjusting Adjusting

(XII) Adjustment

(XIII)

(XIV)

(MANUAL

AO-10

ENGINERS

Dismantling

Notable

FOR

REMODELLING

UNIT

(ONE

MANUAL

the

thread

the

feed

the

shuttle

the

height

the

height

the

safety

the

bobbin

of

the

places

PEDAL

AO-11 64

on assembling and

FOR

tension

release

components 44

race

of

the

of

work clamp

the

wiper

foot

device

thread

winder

V-belt

silicon

oil

tank

disassembling

THE

SUBCLASSES)

LK-280) 60

42

46 47 47 48 49

50 50

51 53

LK-280

ENGINEERS

MANUAL

(STANDARD

ADJUSTING FIGURES).

1. Stop-motion angle

* At

the

2.

Matching

highest

*

Feeding is

above

(Refer

point

the

stops

lowered

the

to

5.5mm(7/32")

feed

to

throat

Fig.15

53°

lower

of

the

needle

cam

when 7—10mm(9/32"'~-25/64")

the

needle

plate.

page9,page

bar.

point

20

than

3)

the

(Fig.l)

Stop-motion

0-

53

angle

Fig.l

Fig.2

3.

Matching

* At

4.

Installing *

*

of

Left

with

Fore

the

stop-motion

the

knife

right

the aft

thread

and

position

center position

trimming

time,

end

of

groove

the

of

needle

shuttle

Needle

Rear

knife

should jibe with the angle @ (Fig.3)

clearance

hole

race

spring

should

end

of

needle

between

is

1.5mm(l/i6").

jibe

the

thread

handling

Fig.3

device

- 1 -

5.

Matching

*

Height

the

of

needle

and

bar

the

shuttle

race

Match

needle

end

bushing.

(Note]

In

(over

raise

higher

*

Matching

When of end

bushing

of the needle

*

Clearance and

of

case

the

needle

of

shuttle

the

bar

the

CFig.4-a)

#30)

the

thgin

the

lower

needle

are

upper

with

needle

thick

is

height

standard.

shuttle

bar

jibed,

and

between

Should

mark

the

bar

line

bottom

lower

thread

to

be

used,

0.5mra(l/64")

mark

and

line the lower

the

bottom

center

the blade point

the

needle

be

of

Upper

Fig.4-a

shuttle

mark

line

Lower

Fig.4-b

should match. (Fig.4-b)

mark

line

0.050.

*

Clearance

and

Should

front

driver

prevent

needle.

*

Clearance

shuttle

(Fig.4-b)

lmm(Fig.4-c)

driver

be

end

as

curving

(Fig.4-d)

should

between

Omm

surface

a

guide

between

the

Make

of

the

to

of

the

be

0.3i(l/100"]-^

needle

the

driver

and

0.5mm(l/64")

0.05~0.l

Fig.4-c

mm

•Omm

Driver

Fig.4-d

- 2 -

6.

7.

Position

*

42-stitch

The

on

the

of

work

*

28-stitch

bartacking

The

on

the

of

work

Position

26th

matching

18th

matching

of

stitch

clamp

stitch

clamp

work

large

machine

wiper

clamp

bartacking

falls

center

foot.

falls

center

foot.

foot

(Fig.5)

machine

mmviSww

26th

18th

Fig.5

stitch(42-stitch

large

stitch(28-stitch

large

bartacking)

8.

* At

* When

Position * At

the

stop-motion

is

at

the

right

of

the

point,

1.5inm(l/6").

the

of

the

stop-motion

position

needle.

wiper

clearance

(Fig.6)

safety

time,

13inm(33/64")

passes

should

adjusting

time:

by

wiper

the

be

plate

to

needle

the

O

Fig.6

Left

right

Top&bottom

(Fig.7)

clearance ® —0.3nim(l/64")

clearance

®—0.3mm(l/64")

- 3 -

Fig.

0.3mm

©

7

9.

Position

*

Position

At

the

of

stop-motion

of

stop-motion

time,

regulating

clearance

cam

between

the stop-motion

roller

*

Position

At

clearance

and

be

should

of

the

low

the

stop

3inmCl/8").

regulating

be

stop-motion

speed

between

link

(Fig.9)

cam

0.5mmCl/64")•

frame

rotation

the

rod

time,

stop-motion

latch

and

(Fig-S)

should

the

cam

Fig.

8

10.

Fig.9

Position

*

The

running and

of

moving

speed

range

at

the pulley should be

(Fig.10)

(Note)

Adjust

so

driving

speed

rotation.

that

to

the

when

and

driving

when

high

speed,

decreasing

components

of ® at both idle

high speed running

0.9*^

pulley

is

rotated

it

changes from low

1.lmm(l/32'^^3/64")

pressing

to

start

that ©

makes

of

plate

1/4

A © 0 O 0)

0.9-1.1

mm

.

...

Fig.10

Q)

-

_J

'

IT

- 4 -

11.

I *

Timing

When the

of

the

last

thread

needle stitch

tension

thread

has

release

loop

slipped

of

out

*

12.

Position of

*

brim

the

from

thread

released.

The

at

rotating

from

cam

When

as

seen

the

comer

tension

the

outer

by 0.

bobbin

the

bobbin winder

from

outer

will

V-belt as

rim

be in contacting

of

bobbin

disc

release

time

is

rim

of

3mmCl/128")

winder

above,

of

the

shown

in

No.2

latch

separated

is

the

. (Fig.11)

assembly

is

in

make

adjustment

bobbin

Fig.12.

case,

feed

idle

winder

position

Tension

(Fig.12)

condition

so

that

wheel

with

Slanted

/

release

part

•

bar

Fig.11

V-belt

- 5 -

for Fig.12

driving

pulley

13. Relation between motor

rotations

are

marked

pulley

on

the

and belt(Power source cycle and

pulley)

number

o£

Power

source

50

Hz

60

Hz

14. Relation

Sewing

specs.

Extreme

light

Synthetic

materials

Standard

weight

Sewing

speed

2000

1700

2000

1700

spm

between

Needle

size

DP X 5

Max.

of

pulley

99.50

87.5

84

74

B7101280000

B710128000B

B7102280000

B710228000B

needle,needle hole guide,sewing specifications

#11

#14(super)

#16

dia.

Needle

guide

D2426282C00

Standard

B2426280000

Driving

47inch

46

hole

r r

belt

MTJVM004700

MrJVM004600

MTJVM004600

OTJVM004500

.

Bartacking pattern

D242684M00

Pressure

belt

35inch

34

35

Knit

Men's

casual

f T

II II

m'JVM003500

MTJVM003400

OTJVM003400

NfrJVM003400.

Sewing

goods,tricot,undergarments

suits,ladies'

wear

decreasing

garments

suits,

•• It

Heavy

materials

Extreme

heavy

weight

(Note)1)For

2)

DPX17

DP X 5

DP X

17

sewing

#21isabout

#18

#19 #21

extreme

ft

B242628000B

heavy

weight

4.5mm(ll/64")

II

materials,use

longer

- 6 -

than

Work

uniforms,coats,

Jean

pants,cold-preventing

clothes

B181728000B

DP

x 5

for

#21

shuttle

etc.

race

ring

(CORRECTIVE

MEASURES

FOR

FAULTY

STITCHES)

This

symptoms breakage

(I)

Thread

*

1)

chapter

such and

slippage

Faulty

needle

any

sewing

Principal

*

Stitches

*

Inadequate

*

Inadequate

*

Bobbin

Corrective

Prevent

*

Verify

If

not,

will

as

thread

inadequate

stitching thread

shape

reasons

skip

length adjustment

thread

measures

the

if

the

adjust

treat

on

slippage,thread thread

symptoms

slips

is

at

is

out formed.

the

first

of

the

too

short.

of

skip-stitching

shuttle

according

the

trimming.

from

trimmed the

race

to

corrective

This

the

needle

stitch.

needle

thread

of

the

and

the

standard

measures

breakage,

is

a

faulty

at

thread.

take-up

first

needle

stitch.

on

skip-stitching,

condition

first

are

or

spring.

in

correcting

faulty

second

correct

procedure.

stitching

needle

by which stitch

relationship.

the

before

*

Lessen

Loosen

shuttle

rotating

adjusting

the

However,

becomes might

of

damaged.

clearance

hit

the

race,

the

shaft

if

too

the

shuttle

Use

clearance

clamp

and

shuttle

to

this

small,

blade

and

caution.

between

screw

adjust

and

O-OS-^O.1mm.

clearance

race

make

the

point

might

for

needle

(Fig.13)

by

be

the

needle

and

the

shuttle.

.-j

n

Shuttle

Clamp

for

Fig.13

screw

shuttle

race

adjusting

race

shaft

- 7 -

*

Inadequate

rotation

of

the

shuttle.

When

lap

it

Also,

the

surface

Watch

*

Prevent

sewing

To

prevent

would be

work clamp

and

the

a

convex

* Watch

Watch

has

started

"floating",

the

shuttle

well.

sometimes

of

carefully.

"concaving"

cloth.

these

best,

foot

work clamp

shapeC Q£| )

the

phase

carefully

to loosen

does

thread

the

shuttle

and

faulty

normally,

with

a concave

foot

of

the

and

see

pierce

the

not

rotate

hards

race.

"convexing"

conditions,

to

process

lowering

as

shown

feed

the

feed

cam.

if

the feed has completely stopped

surface

cam

smoothly,

get

stuck

shape(

plate

in

Fig.14.

of

guide and

of

it

the

to

the

cHa

with

Sewing

)

sewing

adjust

cloth.

the

cloth

feed

Work

Fig.14

when

Should

cam.

Work

clamp

lowering

the needle

the

clamp

foot

plate

needle be

After

cam and

2)

Insufficient

When

moving

tension

the

Worm

length

the feed

releasing

Tension

wheel

length

of

the

cam,

shaft

set

of

nut

trimmed

needle

be sure to adjust the

timing.

releasing

Stop-motion

regulating

Fig.15

needle

thread

(Fig.15)

timing adjustment

Feed cam

cam

thread

after

guide

Standard

it

is

stitch

hole

first

number

for

stitch

controlling

trimmed

from

the

cloth

is

too

needle

at

short,

first

eye

the

at

stitch.

the

thread

time

(Fig.16}

- 8 -

will

of

slip

needle

out

piercing

Thread

slips

Fig.16

*

The

standard length

of

trimmed

needle thread

is

35'-40mmCl-3/8'-l-37/64")

* When

or

the

Adjust

(Refer

Conversely,

too

long.

* When

too

short.

* When

thread

needle

appropriate

0.1^0.

*

If

the

handling

thread

the

tension

thread

the

to

the

tension

the

counter

is

thread

ISmm.

clearance

device

will

timing

Fig.47,

if

the

trimmed

and

tolerance

become

release

by

page

disc

knife

at

the

of

slip

means

timing

No.l

the

bobbin

between

l.Smm

the

shorter.

timing

out

of

4-3

is

pressure

is

too

c£]ii

between

counter

from

tension

).

too

high,

part

thread

the

is

the

fast,

knife

late,

needle.

is

the

of

will

needle

the

is

the

release

the

too

thread

the

be

hole

end

widened,

thread

lever.

trimmed

strong,

moving

trimmed

guide

of

needle

will

length

the

be

knife,

short.

and

eye

the

thread

trimmed

so

the

and

length

be

trimmed

will

generally

The

counter

the

of

be

sporadic

will

before

most

thread

trimmed

too

be

both

knife

short

or

trimmed

the

is

needle

3)

Inadequate

*

adjustment

When

knife

Consequently,

insufficient,

the

will

moving

pull

the

causing

Tension

range

in

the

length

post

of

set

the

of

needle

the

socket

screw

thread

the

of

thread

Fig.17

take-up

immediately

from

to

slip

spring

the

out.

.'Tension

spring

needle

(Fig.17)

set

is

after

to

post

screw

too

the

big,

thread

the

counter

is

end

trimmed.

becomes

- 9 -

*

When

the

moving

range

of

the

thread

take-up

spring

is

too

big,

loosen

the

*

(Note)

4)

Inadequate

*

thread

controller

When

insert

direction.

When

the

tension

the

a

the

tension

matching

return

If

from

can

The

2.2cm(7/8").

If

properly.

the

length

the

not

standard

it's

be

short,

toward

take-up

screw

tension

release

point

length

of

bobbin

formed.

length

(Fig.18)

post

No.2

counter-clockwise

spring

driver

disc

to

is

at

parallel

of

bobbin

the

bobbin

comer

from

slightly

set

is

strong,

the

released,

is

positively

thread

is

too

the

widen

screw

arrow

part,

thread

short,

bobbin

the

and

rotate

direction.

loosen

place

be

sure

at

sometimes

coming

sewing

comer

clearance

the

and

rotate

to

midway

out

shape

is

the

entire

tension

see

that

of

the

tension

it

the

thread

post

toward

the

slanted

tension

socket

set

counter-clockwise

matching

part.

release

bar

screw,

point

If

does

of

the

not

between

hole

*

If

guide

and

*

If

bruised,

Polish

* To

bobbin,

guide.

the

difference

is

will

@

part

it

prevent

the

too

be

it

use

counter

high,

trimmed

of

will

with

forcing

the

of

the

shuttle

invite

some

out

exclusive

knife

level

and

bobbin

short.

bobbin

abrasives.

of

the

bobbin

the

between

thread

race

thread

(Fig.19)

bobbin

needle

the

spring

case

counter

will

be

is

breakage.

thread

for

LK-280

knife

sucked

due

to

model.

in

idle

and

by

spinning

Pig.18

the

Fig.19

needle

counter

of

hole

knife

the

-

10

-

(II)

(A)

Thread

*

Faulty

*

Principle

breakage

condition

reasons

during

stitching

Here,

the

*

Shuttle

*

Thread

*

Bruise

*

Too

*

Bruise

*

Needle

*

Bruise

operation

it

bobbin

small

means

thread

is

bites of

the clearance

of

the

hits

of

the

bruised

into

driver

needle

the

needle

breaking

in

the

between

work

middle

shuttle

hole clamp

of

the

guide

foot

the

of

needle

stitching

driver

thread

and

operation.

the

shuttle

*

Corrective

1)

Bruise

* The (a)

of

with

of

a

the

knife.

Smooth

retreating

needle.

However,

with

the

corrected,

rear

side

If

the

measures

the

shuttle(Fig.20}

part

blade

this

part

the

if

it's

above

verify

of

dimension

is

where

point

with

position

retreated

preventative

and

the

shuttle

is

* Too much

the

bruise

of

the

a

whetstone

of

the

too

see

that

race

insufficient,

tension

cloth

is

shuttle

and

shuttle

much,

measures

the

ring

smooth

of

formed due

and

the

finish

race

skip-stitching

the

blade

dimension

is

same

it

thread

to

blade

it

with

somewhat,

point

of

the

as

shown

out

with

when

the

point

may

slant

in

needle

hitting

becomes

some

prevent

result.

of

the

Fig.21.

a

whetstone.

is

of

like

abrasives

hitting

shuttle

line

part

piercing

the

and

Also,

can

of

needle

a

shape

by

of

the

even

not

the

if

be

Fig.20

-

11

-

Fig.21

CM

d

1

*

The

(D

part is

the

place

where

bruise

is

formed

when

the

needle

becomes

curved

or

broken.

This

be

*

is

given.

The

exchanged

This

does

to

stitch.

*

The

(d)

out

of

happen

careful.

2)

Biting

*

into

When

the position of the shuttle race spring

properly disposed

correct

or

broken and

the

most

and

not

part

the

thread,

its

occur

is

when

frequently occuring bruise, so special

blade point gets

often

the place

causing

so frequently but

the

shuttle

and

position

as shown

the

needle

where

but

where

when

bruise is

when

the thread is

the

thread

synthetic thread

bites into the

in

Fig.3.

thread

caught

it

is

to

shuttle

slips

out

the

thread

attention

formed

or

bruised,

be broken.

when

damaged

is

bad, the needle thread

the shuttle is to

the needle is broken.

it

is

practically

at the time of slipping

This,

to be used, be extremely

too,

race. Set the spring to the

is

damaged

should

impossible

does not

is

be

not

*

When

fault

*

The

but

inadequate

Watch

the R of the ® part of shuttle blade point

results.

installed

if

this

carefully.

dimension

becomes

and

the

Exchange

smaller,

faulty

(Fig.23)

the

shuttle

with large R with a smaller

of ® part of the shuttle race

proper

biting

disposition

in

results.

of

is

too great, the biting

is

7.Smm(19/64")

the

needle

7.5mtn

thread

R.

(Fig.22)

becomes

Fig.22

-

12

-

Fig.23

3)

Bruise

*

Verify

of

if

the

driver

there

is

or

there

is

not

any

0.3~0.5mm

4) Too

*

Conversely,

high.

bruises

shuttle

sewing, spells operation.

thread

part

small

The

(1/64^1/32").

When

causing

on

driver

any

deathknell

path

and

clearance

standard

this

thread

(Fig.24)

the

entire

spring.

bruise

This

finish

its

neighbor

clearance

breakage

if

the clearance is too big, the

on

to

the

is

especially

of

both

area.

between

is

circumference

In

high

the

driver

stitching

true

sides

(Fig.24)

the

driver

between

too

the

small,

speed

spring

of

shuttle

the

of

the

A

and

needle

the

or the needle thread to

shuttle

and

thread

sound

Fig.24

the

driver

does

become

is

0.3-0.5mm

not

slip

extremely

too

of the shuttle gets too

out

welit,

long.

*

The

the blade point of shuttle

5) Bruise

*

When

Also,

containing

6) Needle

When

position

work

If

some

7)

Bruise

*

If

Be

if

clearance between

of

the needle

the

needle

if

abrasion is

lapping

hits

the

the fore

of

clamp

foot

the needle

kind

of

the

breaks, invariably bruise is

work

and

the

work

and

should

sand

needle

hole

formed

agent,

clamp

aft

clamp

cuts

hit

paper

the

feed

the needle is bruised,

sure

the

to

verify

driver

is

the

clearance between the needle and

guiding

driver

came

guide

on

and

foot

amount

foot

the

and smooth

it

the

and

the

shuttle

to the

bottom

the needle,polish the guide with

it

will

is

thread.

work

be

is

increased,

bad,

clamp

it

out.

smooth.

the

foot

invites thread breakage.

needle.

position.

formed

sometimes

needle

and

bruised

should be measured

to the

needle

an

will

when

hit

it,

the

polish

shuttle

inside

when

hole

oil

guide.

wick

installed

of

it

with

and

also

the

-

13

-

8)

Tension

of

thread

when

needle

is

piercing

the

cloth

(B)

* Make

and

pulling.

Thread

*

Faulty

*

Principal

*

Corrective

the

also

breakage

condition

thread

make

reasons

measures

take-up

the

at

pressure

thread

spring's

of

trimming

the

stroke

spring

time

This

needle

at

is

the

forming

*

Defective

*

Moving

*

Height

*

Shuttle

*

Inadequate

surface

*

Position

to

a

thread

last

the

knife

of

small

about

faulty

stitching

normal

thread

counter

race

finish

of

needle

of

scale(6-^8mm)(15/64-^5/16")

30—50gr

condition

or

the

is

bruised

spring

moving

bobbin

thread

releasing

knife

of hole

knife

time

is

thread

at

the

by

thread

without

trimming

timing

bruised

guide

start

which

path

of

the

is

cut

per process.

of

lower

1)

Defective

*

When

tension

* The

is

shown

Condition

needle

1

Too

2

Scattering

3

Short

4

Cut

When

adjustment

adjusting

measures

the

thread

disc

relationship

below.

of

thread

long

§

jumps

in

midway

shaft,

releasing

holder

(Fig.

up

is

move

not

in

between

25)

Tension

Lower

Raise

impossible

the

thread

timing

releasing

the

down

up up

either

thread

release

is

at

too

slow

condition,

releasing

lever

and

thread

timing

the

above or below the

notch.

thread

breakage

and

is

the

needle

thread

cut

occurs.

release

with

thread

the

-

14

-

2) Moving

knife

is

bruised

(Fig.26)

Raise

Lower

Fig.25

*

3)

Height

*

4}

Shuttle

up

down

When

occurs.

there

of

the

In

counter

height

knife before

breakage.

(Refer

to

race

Fig.29

is

bruise

suchacase

knife

of

it

is

6 30

spring

is

along

the

cut

for

bruised(Fig.27)

the

polish

counter

at

the

standard

Fig.26

thread

the

knife

cO=t

passing

parts

is

part

height)

with

too

of

5

parts(A,B,C,D),

some

high,

the

abrasives.

the

moving

5

Fig.27

thread

touches

knife and causes thread

breakage

the

counter

*

When

a

there

case

5) Inadquate

*

6)

When

surface

knife

at

thread

and

correct

Position

*

When

the

will

the

polish

finish

thread

needle

catches

thread

will

be

this

of

moving

needle

is

bruise

it

with

on

theApart

some

abrasives.

of Fig.27,

thread

breakage occurs. In such

of thread path of lower surface of needle hole guide

hole

the

trimming

be

scraped

cut.

fault.

path

of

guide

thread

Be

(Fig.28)

the

and

time

at

careful

is

the

lower

bad

feed

and

comer

and

the

it

moving

out

(^777777m

T '

knife

thread

passes

the

shuttle

Moving

at

the

knife

last

A

Fig.28

stitch,

v

f

J V

Cut

I—'

if

here

the

'

tension

seems

somewhat

to

be

too

strong,

larger.(Standard

make

is

the

matching

1.5mm(l/16"),

-

15

-

clearance

refer

to

with

Fig.2

the

).

moving

knife

(Ill)

Inadequate

thread

trimming

Faulty condition

*

Principal

*

Corrective

1) Inadequate

*

When

all

the

A

the

gone

cutting

somewhat

This

stitching

the

is

bobbin

extremely

reasons * Inadequate

*

Too

small clearance between

and

the

* Inadequate matching * Inadequate

*

Skip-stitching

measures

cutting

moving

or

when

power

braded

power

of

the

knife

knife or counter knife

the knife is brand

of

the

knife

new

moving

knife cuts

a faulty condition in

is

completed,

thread

too

cutting

moving

position

new

becomes

is

long

knife

of

is

and

inadequate.

better

either

not

trimmed

or

too

power

of

clearance of

the

last

extremely abraded or

the cutting surface is inadequate,

than a brand

which

the

or

short.

the

with

shuttle

stitch

even

needle

the

though

thread

needle

or

thread

knife needle hole guide

the race

new

moving

spring

the

moving

knife

blade

knife.

is

*

Relative

(1)

Height

Should be 0.5mm(l/64")

(2) Difference

Counter

(3)

Moving

Should be

(4)

Rattle

dimensions

of

counter

of

level

knife

should be

and

biting

of

moving

of

various

knife

above

between counter knife and needle hole guide

0.1mm

counter

knife

by 0.2Smm(l/lQ0")(Refer

knife

toward up and

Should be 0. OS(l/512")'^-> 0. lmm(l/256")

Counter

Throat

knife

plate

parts

the bottom surface

(Fig.29)

of

throat

higher(1/256") (Refer to Fig,28)

to

Fig.28)

Counter

down

knife

at

Left

direction

the

tip

thread

of

moving

Moving

•Right

plate

knife

Moving

thread

knife

link

knife

Needle

Fig.29

-

16

-

Fig.29»

hole

guide

* When

the

right

thread

is

not

trimmed

*

2) Too

*

* When

Adjust

less

When

Reverse

than

Please

by

when

small

As

by

pinned

of

will

race

the

than

the

0.2mm(l/128")

left

the

0.2mm.

note

making

adjusting.

the

clearance

seen by Fig.30,

0.5mm(l/64"),

between

the

needle

be

torn,

the

thread

but

if

counter

thread

above

(1/128")

that

blade,

the

thread

resulting

there

knife

procedure

the

between

the

but

moving

is

trimmed

are

so

(Fig.29).

is

not

counter

except

@

if

this

after

in

any

that

trimmed

and

make

knife

the

blade

the

needle

part

of

clearance

knife

trimming

this

normally,

and

faulty

remaining

the

slant

the

is

point,

hole

of

slant

constructed

rather

guide

the

of

counter

the

to

and

the needle hole guide

is

too

small,

the

will

stitching

the

thread

needle

be

thread

hole

exceedingly

condition.

does

left

in

be

soft,

the

guide

not

the

knife

counter

easier

so

moving

is

thread

and

long

remain

shuttle

will

knife

for

have

knife

cut

diagonally

will

thus,

or

sometimes

in

race,

be

more

adjustment

this

in

be

the

shuttle

the

mind

length

it

3)

Inadequate

*

defective

condition

When

matching

the

thread

trimming

it

correctly.

Correct

its

thread

inside

(Fig.30)

places

of

Shape

matching

is

can

moving

the

of

not

route

can

remaining

the

of

"the

caught

be

handling device ®

end

of

the

inner

be

classified

thread:

remaining

»

^

the

moving

thus

performed.

of

the

side

thread

knife

correct

Watch

moving

to

of

the

in

following

(Refer

is

inadequate,

thread

and

knife

pass

needle

B

C

is

the

to

Fig.30)

Trimmed

part

match

for

hole.

order

place

of

moving

of

shuttle

according

knife

race

•

Needle

o

Bobbin

to

the

spring

thread

-

17

-

Fig.30

4)

Inadequate

position

of

the

shuttle

race

spring

5)

Skip-stitching

* When

ly.

Needle

*

* When

in

the

caught Adjust

Faulty

Principal

the

case

proper

the

by

the

breakage

condition

position

of

inadequate

position

of

the

stitches

the

knife

needle

reasons....*

of

last

skip

and

the

shuttle

matching

the

shuttle

stitch

at

the

thus

the

shuttle.

This

means

operation

Insufficient

*

Inadequate

last

the

race

thread

the

timing

is

of

the

race

stitch,

(Fig.4)

needle

guide

bad,

moving

spring.

the

will

breaks

of

the

not

front

feed

same

knife

(Fig.3)

needle

be

in

faulty

occurs.

thread

trimmed.

the

surface

does

middle

of

condition

Adjust

not

of

sewing

the

driver

it

get

as

to

*

Corrective

1)

Insufficient

* As shown

the

shuttle

Therefore,

2j

Inadequate

*

When

and

adjust

The

point

in

driver,

to

timing

the

cloth

thus

needle

the

standard

has

measures

guide

Fig.4-d,

the

cause

adjust

feed

adjustment

come

* * *

of

front

unless

needle

so

that

of

feed

movement does

starts

timing.

down

to

Bruise

Needle

Inadequate

may

breakage.

on hits

surface

the

be

curved

the

needle

assembling

of

needle

not

to

"flow",

is

to

needle

match so

7'^10mm(9/32'^

the

when

will

25/64")

hole

work

driver

is

stop

breakage

that

guide

clamp

of

guided

it

pierces

be

guided

before

the

above

foot

moving

at

the

by means

the

occurs.

feeding

the

knife

front

the

needle

stops

throat

cloth

Refer

end

and

of

the

pierces

to

when plate.

surface

hits

driver.

the

Fig.15

the

of

the

cloth

and

needle

-

18

-

3)

Needle

* A

hole

needle,

guide

once

broken,

sometimes

bruises

inside

suface

of

the

needle

hole

4)

Hits

*

5)

Inadequate

guide the

point

The

bruise

with

Also,

are

please

use

the

If

the

foot,

when

extreme

or

due

needle

will

needle

so

a

new

as

there

available

refer

correct

work

needle

changing

caution.

assembling

to

hole

be

caught

hole

easily,

one.

depending

to

ones.

clamp

hits

breakage

are

the

the guide.

is

heat-treated

but

many

page

foot

the

stitch

curving

of

Unless

again

in

by

case

kinds

on

the

6 No.14 and

work

occurs,

of

clamp

size,

moving

the this

the

harder

it

of

usage,

so

apply

knife

needle

bruise

is

bruised

needle

when

causing

than

hole

piercing

is

smoothly

needle

the

needle

toagreater

guide

in

the

cloth,

removed,

breakage.

and

so

it

degree,

combination

Moving

connecting

may

the

needle

should

exchange

with

knife

bruise

not

it

needles

link

(V)

1)

* When

if

the

knife

and

will

needle

knife

CFig.31)

Cautions

Extreme

materials

Thread

removing

installation

connecting

the

needle

hit

the

to

will

on sewing

caution

with

breakage

moving

be

broken

be

should

synthetic

the

knife

link

is

dropped,

bruised.

synthetic

due

to

components,

of

the

is

knife

or

the

be

exercised

thread

heat

moving

forgotten

the

causing

moving

Be

careful.

materials

as

needle

the

for

under:

with

sewing

synthetic

Fig.31

thread

or

mixed

synthetic

Due

to

the

to

should

cause

be

the

taken:

resistance

cloth

to

of

be

the

cut

cJoth

or

stick

at

-

19

piercing

by

melting,

-

time,

following

the

needle

corrective

gets

over-heated

measures

Juki LK-280 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual