JUKI MO-6000S series, MO-6900G series, MO-6900R series MO-6900J series Engineer's Manual

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Page 1

ENGINEER’S MANUAL

29355807

No.E350-01

Super-High-Speed Overlock Machine High-Speed Overlock Machine / Safety Stitch Machine

MO-6000S series MO-6900G series (for Extra-heavy-weight Materials)

High-Speed Variable Top Feed Overlock Machine

MO-6900R series MO-6900J series (for Extra-heavy-weight Materials)

Page 2

PREFACE

This Engineer’s Manual is written for the technical personnel who are responsible for the service and maintenance of the machine. The Instruction Manual for these machines intended for the maintenance personnel and operators at an apparel factory contains operating instructions in detail. And this manual describes “Standard Adjustment”, “Adjustment Procedures”, “Results of Improper Adjustment”, and other important information which are not covered by the Instruction Manual. It is advisable to use the relevant Instruction Manual and Parts List described below together with this Engineer's Manual when carrying out the maintenance of these machines. In addition, for the motor for the sewing machine with thread trimmer, refer to the separate Instruction Manual or Engineer’s Manual for the motor. And for the control panel, refer to the Instruction Manual for the control panel. This manual gives the “Standard Adjustment” on the former page under which the most basic adjustment value is described, and on the latter page “Results of Improper Adjustment” under which stitching errors and troubles arising from mechanical failures are described together with the “Adjustment Procedures”.

MO-6900S MO-6700S MO-6900G MO-6900R MO-6900J

Part No. Part No. Part No. Part No. Part No. 29351707 29351707 29351707 29356409 29363009 29351806 29352408 29352309 29356201 29362803

Model Name of part Instruction Manual Parts List

Page 3

CONTENTS

1. SPECIFICATIONS ............................................................................................. 1

(1) MO-6700S SERIES ........................................................................................................... 1

(2) MO-6900S SERIES ........................................................................................................... 2

(3) MO-6900G SERIES........................................................................................................... 3

(4) MO-6900R SERIES........................................................................................................... 4

(5) MO-6900J SERIES............................................................................................................ 5

2. MODEL NUMBERING SYSTEM ....................................................................... 6

3. STANDARD ADJUSTMENT ............................................................................. 8

(1) Adjusting the needle height............................................................................................ 8

(2) Positioning the throat plate ............................................................................................ 8

(3) Installing position of the needle clamp ....................................................................... 10

(4) Adjusting the length of the lower looper holder (Applicable only to MO-6

16S / MO-6916R, G, J series)........................................... 10

(5) Adjusting the lower looper ........................................................................................... 12

1) Returning amount of the lower looper .................................................................................................... 12

2) Clearance between the lower looper and the needle ............................................................................. 12

(6) Position of the upper looper guide .............................................................................. 14

(7) Positioning the upper looper holder............................................................................ 16

(8) Positioning the upper looper........................................................................................ 18

1) Height of the upper looper ...................................................................................................................... 18

2) Longitudinal position of the upper looper................................................................................................ 18

(9) Adjusting the double chain looper

(Applicable only to MO-6

16S/MO-6916R, G, J series) .............................................. 20

1) Returning amount of the double chain looper......................................................................................... 20

2) Longitudinal motion (Avoid motion) ........................................................................................................ 20

3) Clearance between the double chain looper and the needle ................................................................. 20

(10) Adjusting the height and clearance of the needle guard......................................... 22

1) For 1-needle or 2-needle overlock machine ........................................................................................... 22

2) For safely stitch machine ........................................................................................................................ 22

(11) Adjusting the height of the feed dog ......................................................................... 24

(12) Adjusting the tillt of the feed dog............................................................................... 24

(13) Adjusting the differential feed ratio ........................................................................... 26

(14) Longitudinal position of the feed dog ....................................................................... 26

(15) Adjusting the presser foot.......................................................................................... 28

1) Adjusting the tilt of the presser foot ........................................................................................................ 28

2) Adjusting the micro-lifting mechanism of the presser foot ...................................................................... 28

(16) Positioning the upper knife arm shaft ....................................................................... 30

(17) Positioning the upper and lower knives, and available overedge widths.............. 30

1) Lower knife ............................................................................................................................................. 30

2) Upper knife ............................................................................................................................................. 30

3) Overdging width...................................................................................................................................... 30

(18) Resharpening of the knife .......................................................................................... 32

(19) Position of the thread cam (Applicable only to MO-6

16 series)........................ 32

1) Adjustment of the thread cam................................................................................................................. 32

2) Adjusting looper thread cam thread guides A and B and the looper thread cam nail............................. 32

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(20) Adjusting the throat plate support............................................................................. 34

(21) Adjusting the feed mechanism cover presser.......................................................... 34

(22) Adjusting the looper cover ......................................................................................... 36

(23) Adjusting the cloth chip cover ................................................................................... 36

(24) Adjusting the needle mechanism............................................................................... 38

(25) Position of the upper looper lubrication pin............................................................. 40

1) Orientation of the lubricating pin ............................................................................................................. 40

2) Setting the lubricating pin ....................................................................................................................... 40

(26) Longitudinal momentum of the top feed dog (Top feed amount) ........................... 42

(27) Vertical momentum of the top feed dog.................................................................... 44

(28) Adjusting the height of the top feed dog................................................................... 46

(29) Locus cut of the top feed dog .................................................................................... 48

(30) Adjusting the longitudinal position of the top feed dog .......................................... 48

(31) Adjusting the lateral position of the top feed dog.................................................... 50

(32) Position of the motion of the top feed dog ............................................................... 52

(33) Adjusting the feed bar guides A and B...................................................................... 54

(34) Adjusting the top feed dog pressure......................................................................... 56

(35) Lifting amount of the top feed dog (when operating the pedal).............................. 56

(36) Height of the presser (pedal operation)..................................................................... 58

(37) Lifting amount of the top feed dog (when the presser lifting lever is operated) ... 60

(38) Position of the thread guides and the looper thread take-ups................................ 62

(39) Adjusting soft chain making mechanism.................................................................. 64

1) Replacing the parts with those exclusively designed for making soft chains ......................................... 64

2) Adjustment value .................................................................................................................................... 64

3) Important points in adjustment ............................................................................................................... 65

(40) Position of the thread guides and the looper thread take-ups of MO-6900G (J)... 66

4. ADDITIONAL INFORMATION AND PRECAUTIONS..................................... 68

(1) Thread tension............................................................................................................... 68

1) Strength of tension spring....................................................................................................................... 68

2) Springs used for each model. ................................................................................................................. 68

(2) Upper looper .................................................................................................................. 69

(3) Center-to-center distance of the upper looper holder ............................................... 69

(4) Caution in assembly...................................................................................................... 69

1) Application of sealant ............................................................................................................................. 69

2) Precautions to be taken with respect to the lubricating components...................................................... 71

(5) Kinds of motor pulleys, belts and frame support plate bolts.................................... 72

1) Motor pulleys and belts........................................................................................................................... 72

2) Pat No. of frame support plate bolt......................................................................................................... 73

(6) Inspection and replacement of the cartridge filter ..................................................... 73

5. ADJUSTMENT OF THE NEEDLE HEIGHT AND LOOPER TIMMING........... 74

(1) MO-6000 SERIES ........................................................................................................ 74

6. TROUBLES AND CORRECTIVE MEASURES............................................... 75

7. DIMENSIONS OF TABLE ............................................................................... 87

(1) Semi-sunken type.......................................................................................................... 87

(2) Fully-suken type ............................................................................................................88

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1. SPECIFICATIONS

(1) MO-6700S SERIES

No.

1 2

4 5 6 7 8

9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

Item Model Description

Stitch type F. S. T.

Sewing speed Stitch length Needle gauge Overedging width Differential feed ratio Needle bar stroke Needle tilt angle Needle Presser lifting amount Presser foot pressure Stitch adjusting method Upper knife Differential feed adjustment Weight Lubrication Lubricating oil Needle cooler Needle thread heat remover Micro presser lifting device Motor

7,000 rpm

MO-6704S

1-needle Overlock

machine JIS E13 (USA standard : 504)

–

1.6, 3.2, 4, 4.8 mm

7.0 mm

MO-6714S

2-needle Overlock

machine JIS E24 (USA standard : 514)

2, 2.4, 3.2 mm

3.2, 4, 4.8 mm

6.5 mm

MO-6716S

2-needle Safety stitch

machine JIS E13 + D12 (USA standard : 516)

1.5 to 4 mm

2, 3.2, 4, 4.8 mm

3.2, 4, 4.8, 6.4 mm

7.0 mm

Specifications

0.8 to 4mm

Gathering 1 : 2 (Max.1 : 4), Stretching 1 : 0.7 (Max.1 : 0.6)

24.5mm 20˚

ORGAN DC X 27 (Standard) (DC X 1 can be used as well.)

49N (5Kg)

By pushbutton

Flat knife

By lever with micro adjustment mechanism

28 kg

Gear-type automatic lubrication

* JUKI MACHINE OIL 18 (Equivalent to ISO VG 18)

Optional Optional

Provided as standard

2P 550W (In case of 7,000 rpm)

2P 400W (in case of less than 7,000 rpm)

* JUKI MACHINE OIL 18 (Equivalent to ISO VG 18)

Part No. : MML018900CA (900 m

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(2) MO-6900S SERIES

No.

1 2

4 5 6 7 8

9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

Item Model Description

Stitch type F. S. T.

Specifications

MO-6904S

1-needle Overlock

machine JIS E13 (USA standard : 504)

8,500 rpm

–

1.6, 3.2, 4, 4.8 mm

7.0 mm

MO-6914S

2-needle Overlock

machine JIS E24 (USA standard : 514)

2, 2.4, 3.2 mm

3.2, 4, 4.8 mm

6.5 mm

MO-6916S

2-needle Safety stitch

machine JIS E13 + D12 (USA standard : 516)

1.5 to 4 mm

2, 3.2, 4, 4.8 mm

3.2, 4, 4.8, 6.4 mm

7.0 mm

Gathering 1 : 2 (Max.1 : 4), Stretching 1 : 0.7 (Max.1 : 0.6)

24.5mm 20˚

ORGAN DC X 27 (Standard) (DC X 1 can be used as well.)

49N (5Kg)

By pushbutton

Flat knife

By lever with micro adjustment mechanism

28 kg

Gear-type automatic lubrication

* JUKI MACHINE OIL 18 (Equivalent to ISO VG 18) Provided as standard (Excluding some of subclass machines) Provided as standard (Excluding some of subclass machines)

Provided as standard

2P 550W (In case of not less than 7,000 rpm)

2P 400W (In case of less than 7,000 rpm)

8,000 rpm

0.8 to 4mm

* JUKI MACHINE OIL 18 (Equivalent to ISO VG 18)

Part No. : MML018900CA (900 m

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(3) MO-6900G SERIES

No.

1 2

4 5 6 7 8

9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

Item Model Description

Stitch type F. S. T.

Sewing speed Stitch length Needle gauge Overedging width Differential feed ratio

Needle bar stroke Needle tilt angle Needle Presser lifting amount Presser foot pressure Stitch adjusting method Upper knife Differential feed adjustment Weight Lubrication Lubricating oil Needle cooler Needle thread heat remover Micro presser lifting device Motor

Specifications

MO-6904G

1-needle Overlock

machine JIS E13 (USA standard : 504)

2.5 to 5 mm –

4.8, 10 mm Gathering 1 : 1.75 (Max.1 : 3.8) Stretching 1 : 0.6

MO-6914G

2-needle Overlock

machine JIS E24 (USA standard : 514)

2.5 to 4 mm

2.6 mm

6.4 mm Gathering 1 : 2 (Max.1 : 3.8) Stretching 1 : 0.7 (Max.1 : 0.6)

MO-6916G

2-needle Safety stitch

machine JIS E13 + D12 (USA standard : 516)

2.5 to 5 mm

4.8 mm

4.8, 6.4 mm Gathering 1 : 1.75 (Max.1 : 3.8) Stretching 1 : 0.6

6,000 rpm

28.8 mm 20˚

ORGAN DO X 5

Max. 8 mm

49N (5Kg)

By pushbutton

Flat knife

By lever with micro adjustment mechanism

28 kg

Gear-type automatic lubrication

* JUKI MACHINE OIL 18 (Equivalent to ISO VG 18) Provided as standard (Excluding some of subclass machines) Provided as standard (Excluding some of subclass machines)

Provided as standard

2P 400W

* JUKI MACHINE OIL 18 (Equivalent to ISO VG 18)

Part No. : MML018900CA (900 m

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(4) MO-6900R SERIES

No.

1 2 3

6 7 8

9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27

Item

Model

Description

Stitch type F. S. T.

Sewing speed

Stitch length Needle gauge Overedging width Differential feed ratio Needle bar stroke Needle tilt angle Needle Presser lifting amount Presser foot pressure Stitch adjusting method Upper knife Vertical amount of top feed dog Longitudinal amount of top feed dog Top feed adjusting type Differential feed adjustment Weight Lubrication Lubricating oil Needle cooler Needle thread heat remover Micro presser lifting device Motor

Specifications

MO-6904R

1-needle Overlock

machine JIS E13 (USA standard : 504)

–

3.2, 4, 4.8, 5.6 mm

7.0 mm

MO-6914R

2-needle Overlock

machine JIS E24 (USA standard : 514)

2 mm

3.2, 4 mm

6.5 mm

MO-6916R

2-needle Safety stitch

machine JIS E13 + D12 (USA standard : 516)

1.5 to 4 mm

3.2, 4.8 mm

3.2, 4, 4.8, 6.4 mm

5.5 mm

Gathering 1 : 2 (Max.1 : 4), Stretching 1 : 0.7 (Max.1 : 0.6)

24.5mm 20˚

ORGAN DC X 27 (Standard) (DC X 1 can be used as well.)

49N (5Kg)

By pushbutton

Flat knife

3.5 to 8.5 mm

1 to 7.5 mm (depending on the specifications of the respective machines)

By lever

By lever with micro adjustment mechanism

29 kg

Gear-type automatic lubrication

* JUKI MACHINE OIL 18 (Equivalent to ISO VG 18) Provided as standard (Excluding some of subclass machines) Provided as standard (Excluding some of subclass machines)

Provided as standard

2P 550W (In case of not less than 7,000 rpm)

2P 400W (In case of less than 7,000 rpm)

0.8 to 4mm

* JUKI MACHINE OIL 18 (Equivalent to ISO VG 18)

Part No. : MML018900CA (900 m

Feed type Vertical amount of top feed dog

7,000 rpm (longitudinal amount of top feed less than 6 mm)

6,000 rpm (longitudinal amount of top feed 6 to 8.5 mm)

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−5 −

(5) MO-6900J SERIES

No.

1 2 3

5 6 7 8 9

10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27

Item

Model

Description

Stitch type F. S. T.

Sewing speed Stitch length Needle gauge Overedging width Differential feed ratio

Needle bar stroke Needle tilt angle Needle Presser lifting amount Presser foot pressure Stitch adjusting method Upper knife Vertical amount of top feed dog Longitudinal amount of top feed dog Top feed adjusting type Differential feed adjustment Weight Lubrication Lubricating oil Needle cooler Needle thread heat remover Micro presser lifting device Motor

Specifications

MO-6904J

1-needle Overlock

machine JIS E13 (USA standard : 504)

2.5 to 5 mm –

4.8 mm Gathering 1 : 1.75 (Max.1 : 3.8) Stretching 1 : 0.6

MO-6914J

2-needle Overlock

machine JIS E24 (USA standard : 514)

2.6 mm

6.4 mm Gathering 1 : 2 (Max.1 : 3.8) Stretching 1 : 0.7 (Max.1 : 0.6)

MO-6916J

2-needle Safety stitch

machine JIS E13 + D12 (USA standard : 516)

2.5 to 5 mm

4.8 mm

4.8, 6.4 mm Gathering 1 : 1.75 (Max.1 : 3.8) Stretching 1 : 0.6

28.8mm 20˚

ORGAN DO X 5

Max. 8 mm

49N (5Kg)

By pushbutton

Square knife

3.5 to 8.5 mm

2.7 to 7.0 mm (depending on the specifications of the respective machines) By lever

By lever with micro adjustment mechanism

29 kg

Gear-type automatic lubrication

* JUKI MACHINE OIL 18 (Equivalent to ISO VG 18) Provided as standard (Excluding some of subclass machines) Provided as standard (Excluding some of subclass machines)

Provided as standard

2P 400W

* JUKI MACHINE OIL 18 (Equivalent to ISO VG 18)

Part No. : MML018900CA (900 m

Feed type Vertical amount of top feed dog

6,000 rpm

2.5 to 4 mm

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2. MODEL NUMBERING SYSTEM

MO-6000 SERIES MODEL NUMBERING SYSTEM

MO6 / –

1 2 3 4 5 6 7 8 9 10 11 12 1314 15 16 17 18 19 20 21 22

4 Machine code

7 6700 series 9 6900 series

5. 6 Seam code 03 Splicing

04 1-needle 3-thread overlock (504) 05 For blind hemmong (505) 12 2-needle 4-thread mock safety stitch (512) 14 2-needle 4-thread overlock (514) 16 2-needle 5-thread safety stitch (516) 43 3-needle 6-thread safety stitch 45 2-needle double chainstitch

8 Needle gauge code

0 1-needle B 2.0 mm C 2.4 mm,

2.6 mm (for extraheavy-weight

materials) D 3.2 mm E 4.0 mm F 4.8 mm 1 4.8 mm + 2.0 mm

7 Basic specification code

S Standard G Extra heavy-weight materials R Variable top feed type

J Variable top feed type for

extra heavy-weight materials

9 Overedging width code

A 1.6 mm D 3.2 mm E 4.0 mm

F 4.8 mm H 6.4 mm M 10.0 mm N 18.0 mm

10 Feed dog code

4 2-row 5 1-row 6 3-row 7 4-row

12 Application code Classification based on type of operation

and process

0 Standard

1 For blind stitching

2 For gathering

4 For attaching tape

5 For binding

6 For binding tape D Splicing * E Car mattress

F Soft chain

* In case of the splicing, 13th figure is [1].

11 Material code Classification based on materials to be used

For light-weight materials such as shirts or the like Knit wear only General fabrics Knit wear only such as sweater or the like Medium-weight to heavy-weight materials such as denim or the like For heavy-weight materials Heavy-weight materials for jeans, car mattress, etc.

2 3 4

6 7

Extra light-weight to lightweight materials Light-weight to mediumweight materials Medium-weight to heavyweight materials

Heavy-weight to extra heavy-weight materials

* 6900 only

* * *

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13 Special machine code Special classification of machine, structure and

specification other than gauge set

0 Standard

6 Feed dog provided with a lip

7 Upper looper high throw type

F For swim suits H Upper looper extra high throw type M For zipper

1 For splicing

15 to 18 Device and attachment code

G02/Q141 Presser foot/tape guide for attaching tape

G39/Q141 Presser foot (for sharp curve)/tape guide for

attaching tape L121 Blind hemming ruler S159 Swing type ruffler (pedal-interlocking type for safety

stitch) S161 Swing type ruffler (Manual lever type for safety

stitch) S162 Swing type ruffler (Manual lever type for overlock) N077 Four-fold binder

* The general export specification is for Hong Kong, U.S.A., Japan and Singapore.

20 Machine head code

A Standard machine head

(Common to all specifications)

21 Accessory code

For general export

B For JE

G For China

22 Machine head code

0 Fully-sunken type 1 Semi-sunken type

The numberings after “–” (hyphen) of 19th figure will be used on and after April 1, 2002. They are not described on the catalogue or the like.

Page 12

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Standard Adjustment

3. STANDARD ADJUSTMENT

(1) Adjusting the needle height

When the needle(s) is in the highest position, the needle height from the throat plate surface should be as shown below.

(2) Positioning the throat plate

The needle entry point should be such that the distances listed below are provided between the needle slot edge of the throat plate and the center of needle.

Note that “A=1.8” and “B=1.5” for MO-6 16S (R) - -60H, “A=1.6” and “B=1.3” for MO-69 G, J

(Unit : mm)

Overlock side A 1.3 Double-chainstitch side B 1.0

10˚

6 04

6 14

6 16

1-needle/

2-needle : left

10.5

11.3

11.0

11.3

10.5

11.3

10.5

11.3 13

10.5

11.3

9.8

15.4

14.4

15.4

14.1

2-needle : right

–

– –

9.4

9.9

9.1

9.9

– – –

9.9

9.9 – – – –

12.6 –

The adjustment of needle height for the 2-needle overlock machine should be made in reference to the left needle.

Model

MO- 6 04S(R) - - 0

- 6

50M MO- 6 04S - - H MO- 6 05S - - H

507

50F MO- 6 12S -CE4 -40H MO- 6 14S (R) -B -3 7

20H

40H MO- 6 16S(R)- - 0 MO- 6 16S(R)- - H MO- 6 16S(R)- -60H MO- 6943R - - 7 MO- 6 43S - - H MO- 6 45S - -360 MO- 6903G -0N6 -3D1 MO- 6904G(J)-0F6 -700 MO- 6905G -0M6 -7 0 MO- 6914G(J)-CH6 -700 MO- 6916G(J)-F 6 -700

(Unit : mm)

1-needle

overlock

machine

2-needle overlock

machine

Safety stitch

machine

MO-6900G, J

MO- 6 12S - -

MO- 6 14S (R) -B -

Page 13

−9 −

Adjustment Procedures Results of Improper Adjustment

1) Take off the upper cover, loosen setscrew 2 of needle driving forked crank 1 and move needle driving forked crank 1 up or down to adjust the needle height.

(Caution) Do not fully loosen the setscrew 2 of the needle

driving forked crank 1. If the needle driving forked crank has got out of position laterally when its setscrew was loosened, fully loosen the setscrew and turn pulley to allow the forked crank to turn until it settles by itself. Then tighten the setscrew to fix the forked crank at that position.

1) Loosen setscrews 2 of throat plate base 1 and move throat plate base 1 back and forth to adjust dimension A or B.

™ Any other needle height than

specified here will badly affect the action of the lower looper, the timing for catching the upper looper thread, etc.

™ Improper lateral position of the

needle driving forked crank will cause seizure, play, or other troubles.

™ Improperly positioned throat

plate will cause needle breakage, contact of the needles will the throat plate, or other troubles.

Needle driving shaft

Page 14

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(3) Installing position of the needle clamp

Needle clamp connecting stud 1 should fit with the bottom end of needle bar 2 or spaced within 0 to

0.5 mm.

Standard Adjustment

(4) Adjusting the length of the lower looper holder

(Applicable only to MO-6 16S / MO-6916R, G, J series)

The center-to-center distance should be 26 mm. At this time, the clearance between the end surface of the arm and the neck of the ball should be

3.5 mm.

3.5 mm

0 to 0.5 mm

Butt the needle clamp with the

bottom end of the needle bar.

26 mm

Page 15

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1) Loosen setscrew 3 and adjust, by slightly turning needle clamp 4, the clearance provided between the right-hand side needle

and the lower looper (for 2-needle overlock machine) and the clearance provided between the needle hole in the throat plate and the needle (for safety stitch machine).

™ If the clearance provided

between the needle and the looper is excessive, the needle thread will be likely to skip at the time of tucking.

™ If the clearance provided

between the needle and the looper is insufficient, the needle will break or the looper blade point will be damaged causing thread breakage.

Adjustment Procedures Results of Improper Adjustment

1) Loosen setscrew 1 of the lower looper holder from the rear of the frame. Since it is difficult to accurately measure the center-to-center distance, perform adjustment to provide a 3.5 mm distance between the end surface of the arm and the neck of the ball as illustrated.

™ Increasing the center-to-center

distance will give a smaller stroke of the duble chain looper or lower looper, and decreasing the distance will give larger stroke.

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(5) Adjusting the lower looper

1) Returning amount of the lower looper

The distance between the blade point of the lower looper and the center of the needle should be as follows when the lower looper is at the extreme left of its stroke.

2) Clearance between the lower looper and the needle

The clearance should be 0 to 0.1 mm.

Standard Adjustment

Dimension J

4.0

3.7

3.8

4.0

2.2

3.7

3.8

2.8

3.8

1.4

3.5

1.3

3.3

3.5

Model

Safety stitch

machine

(66.9±0.2 mm)

0 to 0.1 mm

1-needle overlock

machine

2-needle overlock

machine

MO-

6900G,J

(Only MO-69

△△

S,R,

G, J series)

(Unit : mm)

6 04S(R) 6

05S

MO- 6

04S(R)- -

MO- 6 04S - -

MO- 6

14S(R) - -3 7

MO- 6

16S(R) - -

0A5 15

MO- -0A4 to 0E4 -210

0D6 3 0F4 3 0 0F6 500 0H4 50M 0D4 to 0E4 4

0F6

50H BD4 to BE4 BD6 to BE6 BD6 to BF6 20H BE7 4

MO- 6

12S -CE4 -40H

50F

507

500 BE4

MO- 6

16S(R) -DD -

MO- 6 16S(R) -F 6 -60H MO- 6943R -

- 7

MO- 6

43S - - H MO- 6903G -0N6 -3D1 MO- 6904G(J) -0F6 -700 MO- 6905G -0M6 -7

0 MO- 6914G(J) -CH6 -700 MO- 6916G(J) -F

6 -700

MO- 6

12S -DF6 -

MO- 6

14S(R) -

4 H 5

Page 17

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Adjustment Procedures Results of Improper Adjustment

™ Excessive return of the lower

looper tends to cause stitch skipping when filament thread is used.

™ Insufficient return of the lower

looper tends to cause needle thread stitch skipping when spun thread is used.

™ Excessive clearance will often

cause needle thread stitch skipping.

™ Insufficient clearance will cause

needle breakage due to the contact of the looper with the needle, or produce scratches on the blade point of the looper, leading to needle thread breakage or other troubles.

1) Returning amount of the lower looper

1 Loosen setscrew 2 of lower looper support arm 1 and adjust

lower looper 4 to make adjustment of the returning amount.

(Referential information)

1. Radius K of lower looper 4 will be 66.9 mm when the lower looper is inserted into lower looper support arm 1 until it contacts with stopper pin 3 and then is fixed.

2. The rocking angle of the lower looper will be 26˚. (MO-6 S, R) The rocking angle of the lower looper will be 32˚. (MO-69 G, J)

2) Clearance between the lower looper and the needle

MO-6700S Series 1 Loosen setscrew 2 of lower looper support arm 1 to the extent

that it is temporarily tightened. Now, make the adjustment by moving lower looper support arm 1 back and forth.

MO-6900S, R, G, J Series. 1 Loosen setscrew 2 of lower looper support arm 1 to the extent

that it is temporarily tightened. Then finely adjust the longitudinal position of the looper using fine adjustment screw 5.

2 Turn fine adjustment screw 5 clockwise to move lower looper

4 away from the needle.

Turn the screw counterclockwise to move lower looper 4 closer to it.

Page 18

−14 −

Standard Adjustment

Model

6 04S(R) 6

05S

MO- 6

04S(R)- -

(6) Position of the upper looper guide

Vertical position : To be in close contact with the frame guide surface. Laternal position : To be pressed against the upper looper guide support gauge 1.

Safety stitch machine

1-needle overlock machine

2-needle overlock machine

5.8

Upper looper guide support gauge

13131909 13132006

Model

MO-6900G, J

6.3

5.8

4.7

5.5

6.3

5.8

4.2

11545100 12375606

7 5.5

6.3

4.7

4.2

Maker dot

(Unit : mm)

3 0 500

BE4

MO- 6

16S(R) -DD -

MO- 6 16S(R) -F 6 -60H

MO- 6943R -

- 7

MO- 6

43S - - H

MO- 6903G -0N6 -3D1

MO- 6904G(J) -0F6 -700

MO- 6905G -0M6 -7

MO- 6914G(J) -CH6 -700

MO- 6916G(J) -F

6 -700

Frame guide surface

Dimension G Dimension G

0A5 15

MO- -0A4 to 0E4 -210

0D6 3 0F4 3 0 0F6 500 0H4 50M 0D4 to 0E4 4

0F6

50H BD4 to BE4 BD6 to BE6

BD6 to BF6 20H BE7 4

MO- 6

12S -CE4 -40H

507

50F

MO- 6

04S - -

MO- 6

14S(R)- -3 7

MO- 6

14S(R)- -

MO- 6 12S -DF6 -

MO- 6

16S(R) - -

50H

Page 19

−15 −

Adjustment Procedures Results of Improper Adjustment

1) Fit upper looper guide support gauge 1 over gauge fixing pin 3 which has been driven in frame 2 and secure the gauge

with an O ring. Then position the gauge taking the marker dot engraved on it or the chamfering direction as reference.

2) When installin upper looper guide support 4, press it against the gauge while keeping the upper looper guide support into close contact with the frame guide surface, then tighten the screws.

(Caution) Refer to “4- (4) -1) - 7 Various sealants” for the

various sealants.

™ If the upper looper guide has

improperly positioned vertically, it will cause oil leakage or disturbed path of the upper looper with resultant stitch skipping.

™ If the upper looper guide has

been inaccurately positioned laterally, it will cause stitch skipping, or contact with the looper.

Page 20

−16 −

Standard Adjustment

(7) Positioning the upper looper holder

The distance between the bottom surface of the frame and the upper end of the upper looper holder pin 2 should be as shown below when the upper looper holder 1 is at the highest point of its stroke.

Bottom surface of frame

53 mm

0.2mm

Model

6 04S(R) 6

05S

MO- 6

04S(R)- -

Safety stitch machine

1-needle overlock machine

2-needle overlock machine

MO-6900G,J serise

Dimension F

45.0

46.2

48.2

47.3

48.4

46.8

46.9

46.2

48.2

48.4

47.3

48.4

51.2

50.7

51.7

49.3

48.8

(Unit : mm)

MO- 6 14S(R)- -3 7

MO- 6 14S(R)- -

MO- 6

12S -DF6 -

0A5 15

MO- -0A4 to 0E4 -210

0D6 3 0F4 3 0 0F6 500 0H4 50M 0D4 to 0E4 4 H 0F6

50H BD4 to BE4 BD6 to BE6 BD

to BF 20H

BE7 4

MO- 6

12S -CE4 -40H

507

50F

MO- 6

16S(R)- -

500

BE4

MO- 6

16S(R)- DD -

MO- 6 16S(R)-F 6 -60H

MO- 6943R -

- 7

MO- 6

43S - - H

MO- 6903G -0N6 -3D1

MO- 6904G(J)-0F6 -700

MO- 6905G -0M6 -7

MO- 6914G(J)-CH6 -700

MO- 6916G(J)-F

6 -700

5 H

MO- 6 04S - -

Page 21

−17 −

Adjustment Procedures Results of Improper Adjustment

1) Loosen the setscrew of upper looper ball arm 3 and setscrew 5 of the upper looper holder.

2) Adjust the clearances between upper looper bracket 4 and upper looper holder 1 to approximately 0.2 mm respectively, and tighten setscrew 5 of the upper looper holder. (Make sure that the upper looper holder smoothly moves together with upper looper shaft 6.)

3) Then determine dimension F from the bottom surface of the frame to the top surface of upper looper holder pin 2 before tightening the setscrew of upper looper ball arm 3.

(Caution) Replace upper looper holder 1 according to the

needle gauge size.

™ Inaccurately positioned upper

looper holder will cause excessive projection of the upper looper, resulting in stitch skipping, or other troubles.

(Caution) To adjust the upper

looper ball arm, take dimension F as standard. Remember that the projecting amount and the height of the upper looper should eventually be properly adjusted. So, confirm the dimensions related to the upper looper.

Page 22

−18 −

Standard Adjustment

(8) Positioning the upper looper

1) Height of the upper looper

The distance between the throat plate surface and the blade point of the looper should be as follows when the upper looper is at the extreme left of its travel.

2) Longitudinal position of the upper looper

1 The clearance between the upper

and lower loopers should be 0.1 to 0.2 mm when they cross with each other.

2 The clearance between the upper looper 3

and the needle should be 0 to 0.2 mm.

Model

Safety stitch machine

1-needle overlock

machine

2-needle overlock

machine

MO-6900G,J series

Dimension D

11.0

11.3

10.3

11.0

11.8

11.0

11.3

12.8

10.3

11.0

13.6

13.7

12.0

12.9

13.7

MO- 6

04S(R)- - 6

50M

MO- 6

04S - - H

MO- 6

05S - - H

BD4 to BE4

BD6 to BE6 BD

to BF 20H

BE7 4

MO- 6

12S -CE4 -40H

507 50F

MO- 6 16S(R) - - 0

MO- 6 14S(R)- -307

BE4

MO- 6 16S(R)- DD -

MO- 6 16S(R) - F 6 -60H

MO- 6943R

- - 7

MO- 6 43S

- - H

MO- 6903G -0N6 -3D1

MO- 6904G(J) -0F6 -700

MO- 6905G -0M6 -7 0

MO- 6914G(J) -CH6 -700

MO- 6916G(J) -F

6 -700

5 H

Throat plate

(Unit : mm)

MO- 6 12S -DF6 -

Lower looper

0.1 to 0.2mm

0 to 0.2mm

Needle

MO- 6 14S(R)- -

Page 23

−19 −

Adjustment Procedures Results of Improper Adjustment

1) Height of the upper looper

1 Set a hexagon screwdriver onto setscrew 2 at the end of upper

looper bracket 1 to adjust height D.

2 When adjusting the height, pay attention also to the clearance

produced between the upper looper and the lower looper at the time of their crossing.

2) Longitudinal position of the upper looper

1 Loosen setscrew 2 at the top end of upper looper bracket 1

to move upper looper 3 back or forth for positioning the clearance of 0.1 to 0.2 mm between the upper looper and the lower looper at the time of their crossing or the clearance of 0 to 0.2 mm between upper looper 3 and the needle.

™ If the upper looper has been

positioned too high, an excessive clearance will be produced between the upper looper and the needle. As the result, the upper looper thread will fail to catch the needle thread, and stitch skipping occurs.

™ On the contrary, if the upper

looper has been positioned too low, the needle point will hit the looper, causing needle breakage. Also the looper will touch other component when the presser foot goes up.

™ Excessive clearance will cause

stitch skipping.

™ Insufficient clearance will cause

the upper looper to come in contact with the lower looper.

Page 24

−20 −

Standard Adjustment

(9) Adjusting the double chain looper

(Applicable only to MO-6 16S/6916R, G, J series)

1) Returning amount of the double chain looper

The distance between the needle center and the blade point of the double chain looper should be 1.5 to 2 mm when the looper is at the extreme left of its travel.

2) Longitudinal motion (Avoid motion)

The standard minor axis of the elliptical motion should be :

3.0 mm (MO-6 16S, R).

3.5 mm (MO-6916G, J).

Note : The avoid motion should be adjusted in accordance with Needle No.

3) Clearance between the double chain looper and the needle

The clearance should be 0.05 to 0.1 mm.

3.0 to 3.6 mm

0.05 to 0.1 mm

MO-6916G, J series MO-6 16S, R series

Marker

Hole 5

63.2 mm

(63.4 mm)

1.5 to 2 mm

Page 25

−21 −

Adjustment Procedures Results of Improper Adjustment

™ Excessive return of the double

chain looper will cause frequent stitch skipping when filament thread is used.

™ Insufficient return of the double

chain looper will cause frequent thread stitch skipping when a spun thread is used.

™ If the avoid motion is too large,

triangle stitch skipping will often occur.

™ Insufficient avoid motion will

cause the needle point to hit the looper, producing scratches on the needle point or looper.

™ Excessive clearance will cause

frequent needle thread stitch skipping.

™ Insufficient clearance will cause

to looper to hit the needle, leading to needle breakage or scratches on the looper blade point with consequent thread breakage.

1) Returning amount of the double chain looper

1 Loosen setscrew 2 of double chain lopper driving arm 1 to

make this adjustment.

2 Radius M of the double chain looper driving arm 1 will be

63.4 mm when it is lowered until it comes in contact with stopper pin 3.

3 For MO-6916G,J type machines, radius M will be 63.2 mm. 4 Adjust the tilt of double chain looper with setscrew 4. Adjust

the tilt to 1.6 mm.

2) Longitudinal motion (Avoid motion)

1 Open the cover of the adjusting hole on the rear of the frame,

loosen setscrew 5, and put a ø2 rod in the hole. Now, make the adjustment by turning the rod back and forth.

Marker : This side

..... Minimum (for standard to thin needle) A

Marker : Far side

..... Maximum (for thick needles) B

3) Clearance between the double chain looper and the needle

1 Temporarily tighten setscrew 2 in the double chain looper,

and finely adjust the longitudinal position of the double chain looper. Adjust the clearance to 0.05 to 0.1 mm.

MO-6916S,R series only 2 Turn fine adjustment screw 6 clockwise to move the double

chain looper away from the needle. Turn it counterclockwise to move the double chain looper closer to it.

Good needle entry

Bad needle entry

1.6mm

As observed from this side

Page 26

−22 −

Standard Adjustment

(10) Adjusting the height and clearance of the needle guard

1) For 1-needle or 2-needle overlock machine

Make needle guard A lightly come in contact with the top end of needle (bend needle by 0 to 0.05 mm) when the blade point of the lower looper reaches the needle center. The clearance between needle guard B and the needle is 0.1 mm when the needle is at the lowest point of its stroke. The height of needle guard B is 1 mm from the throat plate bottom surface.

2) For safely stitch machine

The safely stitch machine has four needle guards, A, B, C and D. The needle guards A and B are positioned in the same manner as those for the overlock machine. The needle guard C should be positioned 5 mm below the throat plate bottom surface.

Needle guard A

(Traveling needle guard)

Light

touch

the

needle

guard

Needle guard B

Throat plate

1 mm

0.1 mm

Throat plate

5 mm

Lightly touches

0.1mm

Page 27

−23 −

Adjustment Procedures Results of Improper Adjustment

1) For 1-needle or 2-needle overlock machine

1 Adjust needle guard A with setscrews 1 in the needle guard

so that it lightly comes in contact with the needle (bend needle by 0 to 0.05 mm) when the blade point of the lower looper reaches the needle center.

2 To adjust the clearance provided between needle guard B and the

needle when the needle bar is at the lowest point of its stroke, loosen setscrews 2 in the needle guard support and turn needle guard B to adjust the clearance to 0.1 mm.

3 Adjust the height of needle guard B to 1 mm from the throat plate

bottom surface with setscrew 3 in the needle guard.

2) For safety stitch machine

1 Loosen setscrews 4 in the needle guard, and adjust the

clearance provided between needle guard C and the needle so that it lightly comes in contact with the needle (bend needle by 0 to 0.05 mm).

2 Adjust the installing height of needle guard C to 5 mm with setscrew

3 in the needle guard.

3 Adjust the clearance provided between needle guard D and the

needle to 0.1 mm with setscrews 5.

(Caution) Check again the clearance provided between needle

guard B and the needle after adjusting the height of needle guard C.

™ Excessively close contact between

the needle guard A and the needles will lead to needle bend or stitch skipping.

™ A clearance left between the

needle guard A and the needles will cause the looper blade point to come in contact with the needles, leading to needle or blade point breakage, or other troubles.

™ If the needle guard B is too high,

thread loops will be damaged with resultant stitch skipping. Also, double chain loops will be affected, causing double chain stitch skipping.

™ If the needle guard B is too low,

the needle cooling felt will be lowered, resulting in deteriorated effect of the cooling and needle guard.

™ Excessive clearance between the

needle guard B and the needle will cause stitch skipping due to needle shake. On the contrary, insufficient clearance will cause the needle guards to catch the needles between them, leading to wear on the needle guards and scratches on the needles.

™ If the needle guard C is too high,

the needle thread loops will be damaged, and stitch skipping occur. If it is too low, the needle points will be crushed.

™ If the clearance between the

needle guard C and the needles is too large, the double chain looper blade point will come in contact with the needles, causing the breakage of the needles, causing the breakage of the needles or looper blade point.

No clearance left between them will

cause them to come in excessively close contact with each other, and wear on the needle guard and scratches on the needles will occur.

™ Excessive clearance left between

the needle guard D and the needles will cause stitch skipping due to needle shake, and insufficient clearance will cause the needle guards to catch the needles between them, leading to wear on the needle guards and scratches on the needles.

Page 28

−24 −

Standard Adjustment

(11) Adjusting the height of the feed dog

The height of main feed dog 2 from the top surface of the throat plate 1 should be as follows when it is at its highest posion.

Auxiliary feed dog 4 is 0.5 mm lower than main feed dog 2.

(12) Adjusting the tillt of the feed dog

Model Dimension A

MO-6 00S Series 1.0

MO-6904G Series 1.3 MO-6914G Series 1.2 MO-6916G Series 1.1

0.5 mm

Tilt of the feed dogs when the feed dogs have come up most.

When the feed dog juts out the top surface of the throat plate

Needle

entry

Top surface of the throat plate

Feed dog is leveled.

Model Dimension A Dimension B

MO-6 00S Series 1.0 (1.2)

MO-6904G Series 1.3 (1.5) MO-6914G Series 1.2 (1.4) MO-6916G Series 1.1 (1.3)

(Unit : mm)

Front up

Needle

entry

(Unit : mm)

Page 29

−25 −

Adjustment Procedures Results of Improper Adjustment

1) Adjust the height of main feed dog 2 to dimension A with setscrew 5.

2) Adjust the height of differential feed dog 3 with setscrew 7 so that there is no difference in level between main feed dog 2 and differential feed dog 3.

3) Adjust the height of auxiliary feed dog 4 with setscrew 6 so that it is 0.5 mm lower than main feed dog 2.

1) Use the tilt of the feed dog when it is in its highest position as a reference and adjust so that the feed dog is flush with the throat plate when the feed dog juts out the throat plate.

2) Feed bar shaft 8 consists of an eccentric shaft. Loosen setscrew 9 to perform adjustment.

When the marker line is set at middle

.....The feed dog will be flat.

When the marker line is set at bottom

.....The feed dog will be tilted with its front up (in the arrowed

direction).

When the marker line is set at top

.....The feed dog will be tilted with its front down.

(Caution) The marker line should be used just as the reference

since it slightly differs with that of each machine due to the disparity of the components. Confirm the accurate tilt of the feed dog by observing the feed dog itself.

™ If the feed dogs are too high, the

needles will be deflected and broken when sewing heavyweight materials. The feed dogs will tend to suffer scratches when sewing light-weight materials. Puckering will frequently occur.

™ If the feed dogs are too low,

insufficient feed power will result.

™ If the auxiliary feed dog is too

high, chain-off thread will be often jammed.

™ If the main feed dog and

differential feed dog are set at different heights, proper differential feeding action will be hindered.

™ When tilted with the front up

Good material catching will be

obtained.

™ When tilted with the front down

Uneven feed and puckering will

be effectively prevented.

Page 30

−26 −

Standard Adjustment

(13) Adjusting the differential feed ratio

(Max, gathering)

Gathering: 1: 4

Stretching: 1: 1.3

Center

of nut

Lower

marker

line

(Standard)

Gathering: 1: 2

Stretching: 1: 0.7

Pin at its highest position

(Max, stretching)

Gathering: 1:1.6

Stretching: 1:0.6

Washer

Pin at its lowest position

MO-6900G, J Serise

Center of nut

(MO6904G (J), MO6916G (J))

Gathering: 1: 1.75

Stretching: 1: 0.6

(MO-6914G (J)) Gathering: 1:2.0

Stretching: 1:0.7

Center of nut

Halfway

between

upper

marker line

and lower

marker line

Slightly

lower than

lower

marker line

MO-6000S, R Serise

(14) Longitudinal position of the feed dog

When the feed pitch is maximized and the differential feed ratio is also maximized, the clearances of the front and rear ends of the feed dog, and the throat plate should be spaced approximately 0.5 mm respectively.

0.5mm

Page 31

−27 −

Adjustment Procedures Results of Improper Adjustment

1) Remove cover 1 on the rear of the frame and loosen main feed pin and nut 3.

2) Move main feed pin 2 up or down to adjust the differential feed ratio.

3) Adjust so that the lower engraved marker line on main feed rocker 4 aligns with the center of nut 3. (Standard)

4) When adjusting the maximum stretching, adjust main feed pin 2 to the highest position.

5) When adjusting the maximum gathering, adjust main feed pin 2 to the lowest position.

6) After performing adjustment, tighten the main feed pin and nut 3, and install cover 1.

1) Remove the cover on the rear of the frame, loosen main feed bracket clamping screw 1 and differential feed bracket clamping screw 2, and adjust the clearances provided between the front and rear ends of the feed dogs and the slots in the throat plates to approximately 0.5 mm. Then tighten main feed bracket clamping screw 1 and differential feed bracket clamping screw 2.

™ If the clearance provided

between the throat plate and the feed dog is too small, they will come in contact with each other when the sewing machine runs at high speed.

Page 32

−28 −

Standard Adjustment

(15) Adjusting the presser foot

1) Adjusting the tilt of the presser foot

The presser foot should be positioned so that the feed dogs go down under the specified presser foot pressure, and the presser foot sole comes in contact evenly with the throat plate surface.

2) Adjusting the micro-lifting mechanism of the presser foot

Throat plate

Page 33

−29 −

Adjustment Procedures Results of Improper Adjustment

1) Adjusting the tilt of the presser foot

1 Turn the handwheel and place the feed dog in the position

where the feed dog does not jut out the top surface of the throat plate.

2 Loosen setscrew 1 and adjust so that the presser fopot sole

comes in contact evenly with the throat plate top surface. Then tighten setscrew 1.

(Reference) Accurate adjustment can be made by using two

pieces of thin paper to check for even drawing-out tension. In addition, even contact of the presser foot with the throat plate top surface is achieved rather easily by tightening the screw while pushing the right side of the presser foot.

2) Adjusting the micro-lifting mechanism of the presser foot

1 When moving presser lifting lever 2 just a little, perform it with

fine adjustment screw 3.

™ Uneven contact will result in bad

straight material feed, weak feed power, or puckering.

Page 34

−30 −

Standard Adjustment

(16) Positioning the upper knife arm shaft

The upper knife shaft should be positioned 34 mm above the top surface of the throat plate when it is at its highest position.

MO-6 16S(R)-F 6-60H : 35 mm

(17) Positioning the upper and lower knives, and available overedge widths

1) Lower knife

2) Upper knife

3) Overedging width

Overedging width can be adjusted from 1.6 to 6.4 mm.

34 mm

Throat plate

Lower knife

Upper knife

0.5 to 1 mm

Page 35

−31 −

Adjustment Procedures Results of Improper Adjustment

1) Remove the upper cover, loosen setscrew 2 in upper knife driving arm 1, and turn upper knife shaft 3 to adjust the position from the top surface of the throat plate to 34 mm.

(Caution) Be sure to fully tighten the setscrew since upper

knife shaft 3 is subjected to high load.

1) Lower knife

1 Adjust the vertical position of the lower knife by screw 1 so

that the blade top aligns with the top surface of the throat plate.

2 Tighten screw 2 after bringing the upper knife to its lowest

position of its stroke.

2) Upper knife

1 Adjust the position of the upper knife by screw 4 so that the

engagement with the lower knife is 0.5 to 1 mm when the upper knife is in the lowest position of its stroke.

(Caution) Adjust the lateral position of the lower knife by screw

2. Adjust the lateral position of the upper knife by screw

3. After performing adjustment, be sure to fix the knife.

Otherwise, the durability of the knife will be affected.

3) Overedging width

1 Adjust the overedging width in the following way :

Laterally position the upper knife before loosening screw 2. Tighten screw 2 when the upper knife has settled by itself under the pressure applied by the spring. Repeat this adjustment procedure to obtain desired overedging width.

™ Improperly positioned upper

knife arm shaft will come in contact with the frame.

If it is moved with the position of

the upper knife unchanged, proper engagement of the knives will be disturbed, prohibiting sharp cutting of the knives.

™ The lower knife, if positioned too

high, will catch materials or cause no contact of the presser foot with the throat plate top surface.

™ If the lower knife is positioned

too low, the cutting width will be changed or materials will be caught by the lower knife.

™ The upper knife, if positioned too

high, will fail to cut materials.

™ Unsharp cutting or abnormal

wear on the knives will result unless the lower knife is laterally positioned and fixed at a position where it has settled by itself under the upper knife spring.

Page 36

−32 −

Standard Adjustment

(18) Resharpening of the knife

(19) Position of the thread cam (Applicable only to MO-6 16 series)

1) Adjustment of the thread cam

2) Adjusting looper thread cam thread guides A and B and the looper thread cam nail

MO-6 16 series

Lower knife gauge Part No. 11996907

10˚

55˚

Level

Page 37

−33 −

Adjustment Procedures Results of Improper Adjustment

1) When the knives have become dull, fully resharpen lower knife 1 until the contact mark of it disappears.

2) When the upper knife has become dull, replace it with a new one. (This is because the upper knife is a serrated carbide knife.)

1) Adjusting the thread cam

1 Adjust the position of the thread cam by its setscrew 1 with

the needles at their upper dead point so that the straight section of the thread cam is leveled.

2 Laterally position the thread cam so that the looper thread cam

nail is located at the center of the thread cam groove.

[How to check for proper positioning]

Check that the thread cam releases the looper thread when the needle tip begins to come out of the bottom surface of the throat plate by 0 to 1 mm.

2) Adjusting the looper thread cam thread guides A and B and the looper thread cam nail

1 Install looper thread cam thread guides A 2 and B 3 at the

center of the slots with setscrews A 4 and B 5.

2 Install looper thread cam nail 6 with setscrew 7 so that the

straight section of the forked portion is leveled.

™ If the 10˚ angle of the lower knife

is exceeded, the durability of the knife will be deteriorated, often resulting in blade chipping.

™ If the angle is smaller than 10˚,

the knife will be dull.

™ If the 55˚ angle is not observed,

the knife may catch materials.

™ If the timing of the thread cam

is too early, the needle point will fail to enter a thread triangle, resulting in looper thread stitch skipping.

™ If the timing of the thread cam

is too late, puckering and loose looper thread stitches will results.

™ If the chain looper thread guide

is moved away from you, the take-up amount of the lower looper thread will decrease. In this case, puckering may result there by impairing the feeling of the finished product.

0 to 1 mm

Thread

Throat plate

Page 38

−34 −

Standard Adjustment

(20) Adjusting the throat plate support

(21) Adjusting the feed mechanism cover presser

Uniform contact

(22) Adjusting the looper cover

™ The looper cover should smoothly close without coming in contact with upper knife 1 when slowly

closing looper cover 2 with upper knife 1 in its lowest position of its troke.

Frame

Cloth chip

cover

Page 39

−35 −

Adjustment Procedures Results of Improper Adjustment

1) Loosen setscrews 1 and adjust so that throat plate support 2 should not come in single-sided contact but come in uniform contact with throat plate 3 using setscrews 1.

1) Loosen setscrew 1 and press feed mechanism cover presser 2 in the direction of arrow.

2) Press feed mechanism cover 3 and tighten setscrew 1 so that the feed mechanism cover should not rise.

(Caution) Check that feed mechanism cover 3 is pressed so

that it should not rise.

™ If the throat plate support comes

in single sided contact with the throat plate or does not come in contact with it, the throat plate will vibrate severely.

™ If the feed mechanism cover is

not fully pressed and the cover rises, oil leakage will be caused.

1) Close looper cover 2, loosen setscrew 3, and move looper cover guide plate 4 back and forth until the looper cover is brought to a position where the cover smoothly closes.

2) Move looper cover guide plate 4 until it slightly comes in contact with looper cover receiving bracket 5. Now, fix the guide plate by tightening setscrew 3.

Page 40

−36 −

Standard Adjustment

(23) Adjusting the cloth chip cover

™ When cloth chip cover 3 is pressed away from you, it should not rattle.

In addition, the cloth chip cover should not come in contact with upper knife 1 and lower looper 4.

(Located inside)

Page 41

−37 −

Adjustment Procedures Results of Improper Adjustment

1) Loosen setscrew 5 and temporarily tighten the setscrew with cloth chip cover stopper 6 raised.

2) Loosen setscrews 7 in the cloth chip cover, and adjust the longitudinal position of cloth chip cover 3.

3) Loosen setscrew 5 in the cloth chip cover stopper again, and press cloth chip cover stopper 6 downward until the stopper slightly comes in contact with looper cover 2. Now, tighten setscrew 5.

4) Finally, confirm that cloth chip cover 3 comes in contact with neither upper knife 1 nor lower looper 4.

Page 42

−38 −

Standard Adjustment

(24) Adjusting the needle mechanism

1. Disassembling

2. Adjustment

Needle

drive arm

0.1 mm

3 (It should not stay inside the

pin as the concave.)

Chamfered portion should be positioned inside.

Page 43

−39 −

Adjustment Procedures Results of Improper Adjustment

1. Disassembling

1) Remove top cover 7 and side cover 8.

2) If packing 9 of the top cover has been adhered on the frame, also remove packing 9.

3) Remove needle front plug !1.

4) Loosen setscrew !0 of needle lubricating pin 4 and remove needle lubricating pin 4.

5) Remove needle bar upper bushing cap screw !2 and loosen setscrew !3 in the needle drive pin.

6) Fitting needle drive pin 2 in the hole on the frame side, thrust the pin until it can be drawn out.

2. Adjustment

1) Bring needle bar 1 to the lower dead point.

2) Adjust oil wick 3 in needle drive pin 2 so that it should be flush with the chamfered plane of the pin. (If oil wick 3 sinks inside the chamfered plane as the concave, oil will not be fed smoothly.)

3) Install needle lubricating pin 4 in place with its oil inlet 6 faced above.

4) Adjust with setscrew !0 so that the clearance between needle lubricating pin 4 and needle drive connecting link 5 is 0.1 mm. (It is convenient to use a 0.1 mm clearance gauge or the like.)

™ If the oil wick is installed in the

needle drive connecting link pin inside the pin as the concave, oil will not lubricated properly resulting in seizure.

™ If the clearance provided

between the needle lubricating pin and the needle drive connecting link is too small, the related components will come in contact with each other.

™ If the clearance provided

between the needle lubricating pin and the needle drive connecting link is too large, oil wll not be fed properly resulting in seizure.

™ If the oil inlet does not face

upward, oil will not be fed resulting in seizure.

Page 44

−40 −

Standard Adjustment

(25) Position of the upper looper lubricating pin

1) Orientation of the lubricating pin

Oil inlet 2 of upper looper lubricating pin 1 should face upward.

2) Setting the lubricating pin

The clearance provided between upper looper lubricating pin 1 and upper looper bracket 4 should be 0.15 mm.

0.15 mm clearance

Page 45

−41 −

Adjustment Procedures Results of Improper Adjustment

1) Orientation of the lubricating pin

1 When upper looper lubricating pin 1 is set with oil inlet 2

faced upward, lubricating hole 3 is in the lower section as observed from this side.

2) Setting the lubricating pin

1 Remove the oil reservoir, loosen the setscrew and adjust the

clearance provided between upper looper lubricating pin 1 and upper looper bracket 4 to 0.15 mm using a 0.1 5mm clearance gauge or the like.

™ If the oil inlet does not face

upward, oil will not be fed resulting in seizure.

™ If the clearance provided

between the upper looper lubricating pin and the upper looper bracket is too small, the related components will come in contact with each other.

™ If the clearance provided

between the upper looper lubricating pin and the upper looper bracket is too large, oil will not be fed resulting in seizure.

Page 46

−42 −

Standard Adjustment

(26) Longitudinal momentum of the top feed dog (Top feed amount)

Longitudinal momentum (top feed amount) of the top feed dog is possible up to 7.5 mm.

Longitudinal momentum (top feed amount)

Max.

7.5mm 7mm

7mm

Standard MO-6916R-F 6- H MO-6900J

Min.

1mm

2.5mm

2.7mm

Decreases

Increases

Decreases

(Caution) Motion of the top feed is not interlocked with the motion of the bottom feed. The

longitudinal momentum (top feed amount) of the top feed is determined only by the position of top feed lever 4.

Page 47

−43 −

Adjustment Procedures Results of Improper Adjustment

1) Changing the longitudinal momentum (top feed amount) of the top feed dog

1 Loosen top feed lock nut 3 and move top feed lever 4 in the

direction of the arrow mark to adjust the stroke.

2 When top feed fine adjustment screw 5 is used, it is possible

to slightly move top feed lever 4.

2) Changing the maximum momentum

1 Loosen setscrew 1 in the differential feed adjustment stopper

and lower the stopper to increase the maximum momentum and raise the stopper to decrease it.

2 After the adjustment, securely tighten setscrew 1 in the

differential adjustment stopper.

3) Changing the minimum momentum

1 Loosen setscrew 2 in the differential feed adjustment stopper

and lower the stopper to increase the minimum momentum and raise the stopper to decrease it.

2 After the adjustment, securely tighten setscrew 2 in the

differential adjustment stopper.

™ If the min. stroke is decreased

to 1 mm or less, the components mounted inside the machine head may come in contact with among one another. It is therefore necessary to set the min. stroke to 1 mm or more.

™ If the min. stroke is decreased

to 2.5 mm or less for safety stitch machines of 50H or 60H type, the top feed dog may come in contact with the upper looper holder. It is therefore necessary to set the min. stroke to 2.5 mm or more for the aforementioned types of machines.

Page 48

−44 −

(27) Vertical momentum of the top feed dog

Standard Adjustment

Relation between the position of vertical adjustment pin and the vertical momentum

* In case of adjusting the position of vertical

adjustment screw 2, check that the pin does not come in contact with upper knife support, needle clamp, etc. Then securely tighten vertical adjustment screw 2.

Striking to top end of groove

Marker line position A

Marker line position B

1 to 1.5 mm on this side from striking to top end of groove

(18.7˚)

(24.6˚)

(31.8˚)

(42.5˚)

Vertical adjustment arm

Assembling position of locus cut base and exhaust slot support

Move exhaust slot support 4 to the right. (Screw : left side of slot)

Move locus cut base 3 to the left. (Screw : right side of slot)

0.45mm

Check that the locus cut screw is adjusted to the position (almost the center) of the aforementioned dimension of the vertical adjustment arm support section.

Vertical momentum

3.5mm

5.0mm

6.5mm

8.5mm

Adjusting position Striking to end of groove. Marker line position A Marker line position B 1 to 1.5 mm on this side from

striking to end of groove

Application Light weight material Light- to medium-weight materials Medium- to heavy-weight materials Extra heavy-weight materials

Page 49

−45 −

Adjustment Procedures Results of Improper Adjustment

1) Remove the top cover, locus cut base 3 and exhaust slot support 4.

2) Loosen vertical adjustment nut 1 and move vertical adjustment pin 2 to a proper position.

3) After the adjustment, stop locus cut base 3 and exhaust slot support 4 at the position as shown in the figure.

™ When the position of vertical

adjustment pin 2 is changed, the vertical momentum of top feed dog changes.

™ When vertical adjustment pin 2

is moved toward the top end of vertical adjustment arm, the momentum is decreased and when it is moved to the root, momentum is increased.

™ When the vertical momentum is

increased, jumping occurs and noise may occur at high speed. In this case, tighten the upper

Page 50

−46 −

Standard Adjustment

(28) Adjusting the height of the top feed dog

Adjusting the position of lowest point of the top feed dog

It is standard that the top feed dog is 1.0 mm (safety stitch machine : 0.8 mm) from the top surface of the throat plate when the top feed dog is in the lowest point of its stroke. It is possible to adjust the position to approximately 1.0 mm above or below the standard adjustment.

(Reference) The standard of the height of the bottom feed dog (main and differential feed dogs)

is 0.8 mm from the top surface of the throat plate and flush with it when the bottom feed dog is in the highest point of its stroke.

Approx. 1 mm

Approx. 2 mm

a (Height of top feed dog)

b (Height of bottom

feed dog)

Throat plate

™ Adjusting top/bottom feed dogs of various models of the subclasses

0 -30 1.0 0.8

500 50M 1.0 1.0

- 0 1.0 0.8 4

-30 0.8 0.8

-50H 1.0 0.8

-60H 1.5 1.3 1 6 -307 0.8 0.8 0F6 -700 1.5 1.3 CH6 -700 1.4 1.2 FH6 -700 1.3 1.1

Top feed dog height a Bottom feed dog height b

MO-6904R

MO-6914R

MO-6916R

MO-6943R MO-6904J MO-6914J MO-6916J

Model name

(Unit : mm)

Page 51

−47 −

Adjustment Procedures Results of Improper Adjustment

1) Loosen setscrew 1 in the top feed dog and move top feed dog 2 up or down to adjust the height.

(Caution) 1. Perform the adjustment in the state that the

standard top feed pressure is applied.

2. Top feed dog 2 is removed and personal injuries may occur. Use a rather large-sized screwdriver and securely fix setscrew 1 in the top feed dog.

™ When top feed dog is installed

higher than the standard

Sewing of heavy-weight

materials is possible.

However, a clearance is

provided between top and bottom feed dogs, and partial shirring performance of lightweight materials or feed force is decreased.

™ When top feed dog is installed

lower than the standard

Partial shirring performance or

feed force is increased. However, when overlapping amount of top and bottom feed dogs is excessively increased, feed dog defect is apt to occur. Besides, sound may become higher.

™ In case of sewing heavy-weight

materials

It is possible to sew even when

vertical stroke is increased.

Refer to "(27) Vertical

momentum of the top feed dog".

Page 52

−48 −

Standard Adjustment

(29) Locus cut of the top feed dog

Locus cut mechanism makes longer the section where the feed dog actually feeds cloth by leveling the lower side of the locus of top feed dog motion. By this mechanism, the effect of prevention of irregular stitches can be obtained when sewing materials thicker than mediumweight ones such as knitted fabrics or the like although the effect is less for light-weight materials. The locus cut mechanism does not work in the state of delivery.

Set the standard of cut amount to approximately 0.5 mm.

Locus of feed dog

Cloth

Range of effective feed

Cut amount

(30) Adjusting the longitudinal position of the top feed dog

Clearance between top feed dog 2 and the groove of presser 3, when top feed stroke0 is maximum, is as shown in the list below. Clearance between top feed dog 2 and groove of presser 3 when top feed dog 2 travels to the front end = dimension A

Thrust collar

Top feed arm C

Model name dimension A

MO -6916R-F

6 -50H 0.8

F 6 60H MO -6943R -1D6 -307 1.0 All models of MO-6900R, and J 0.5

excluding aforementioned models

(Unit : mm)

Page 53

−49 −

Adjustment Procedures Results of Improper Adjustment

1) Remove the top cover.

2) Turn the handwheel to bring the top feed dog to the lowest point of its stroke.

3) Loosen locus cut screw nut 1 and tighten locus cut screw 2. Then the top feed dog rises.

4) When a proper cut amount is obtained, tighten locus cut screw nut 1 so that locus cut screw 2 does not turn.

5) Loosen the setscrew in the top feed dog and lower the top feed dog to the position where it bites cloth.

(Caution) 1. When using the machine with locus cut, use

the machine at a speed of 5,500 rpm or less.

2. When the cut amount exceeds 1 mm or more, a forced load is applied to the mechanism. Use the machine with locus cut of less than 1 mm.

™ The lifted amount from the

lowest point in the step 3) is the cut amount. In this state, the clearance between top and bottom teeth is increased as large as the cut portion and feed force is decreased. Be sure to adjust the biting amount of cloth by lowering the top feed dog in the step 5).

1) Remove the top cover and loosen clamping screw 1 in the top feed arm C to adjust the position.

2) The tightening torqueses of clamping screw 1 in the top feed arm C after the adjustment is 80N.

(Caution) 1. Do not completely loosen clamping screw

1 in the top feed arm C.

2. If clamping screw 1 in the top feed arm C is loosened and has moved to the right or left, completely loosen it, turn the handwheel and tighten it at the position where it comes naturally.

™ When dimension A is improper,

top feed dog 2 comes in contact with presser 3, and noise occurs. Besides, the dimension is excessively improper, the top feed dog may come in contact with other components in the frame. Be careful when performing the adjustment.

Page 54

−50 −

Standard Adjustment

(31) Adjusting the lateral position of the top feed dog

Clearance between top feed dog 4 and presser 3 is 0.2 mm. a = a’ (0.2 mm) b = b’ (0.2 mm)

(Caution) 1. Adjust the position only when there is a concrete problem that presser 3 and top

feed dog 4 come in contact with each other and noise occurs, the left and right clearances are excessively different from each other and trouble occurs, etc.

2. When the adjustment value is improper, there is the possibility that contact among the components occurs, a bad influence is given to the durability of the sewing machine or the like since the top feed mechanism is strictly assembled because of the space. So, be careful.

a a’

b’

Top feed arm C

Page 55

−51 −

Adjustment Procedures Results of Improper Adjustment

1) Loosen the setscrew in the feed bar guide B. Refer to “(33) Adjusting the feed bar guides A and B”.

2) Remove the top cover and loosen setscrew 1 in the top feed arm C. Refer to (30) Adjusting the longitudinal position of the top feed dog.

3) Loosen the setscrews in thrust collars 2 located on the both sides of the horizontal shaft and move the set of horizontal shaft, top feed bar and top feed dog to the predetermined position in the thrust direction (direction you desire to adjust the position). Then fix two thrust collars 2 at the position.

(Reference) When loosening the setscrews in thrust collars

2, do not simultaneously loosen the two setscrews. First, loosen thrust collar 2 on the side of moving direction and fix it at the predetermined position. In the state of pressing it in the direction, check that contact at the lateral position or at the top feed mechanism does not occur. After the checking, move and fix the remaining thrust collar 2. The aforementioned procedure can perform good adjustment.

4) Tighten the respective setscrews by reversing the aforementioned order and perform the adjustment.

™ Excessive move in both

directions of cloth base side and handwheel side produces the contact of top feed bar with the respective sections of top feed mechanism. (Fully check the change of torque, engagement, or noise at the time of adjustment.)

Page 56

−52 −

Standard Adjustment

(32) Position of the motion of the top feed dog

Adjusting the position of the motion of the top feed dog Loosen the setscrew in horizontal arm A 1 and move the position of horizontal arm A 1 to change the position of the motion of the top feed dog.

™ Intermediate constant

When the pitch of the top feed dog is increased, the top feed dog extends to the front and rear.

™ Rear constant

When the pitch of the top feed dog is increased, locus extends to the front while the most retarded position of the top feed dog is constant.

™ Front constant

When the pitch of the top feed dog is increased, locus extends to the rear while the most advanced position of the top feed dog is constant.

Position of the motion of the top feed dog changes by changing the installing angle of ˚ horizontal arm A 1 and horizontal arm B 2.

Intermediate constant (standard)  Rear constant  Front constant

Horizontal feed link 4 should not sway to the right or left.

Page 57

−53 −

Adjustment Procedures Results of Improper Adjustment

™Intermediate constant

1) Make horizontal arm A 1 in the state of temporary tightening, turn the handwheel and adjust the top feed dog to the position where it is desired to be constant.

2) At the position, tighten horizontal arm A 1 at the position where the top feed dog does not move even when the top feed lever is moved.

3) Loosen horizontal arm C 3 at the position where the top feed dog does not come in contact with the front or rear of the groove of the presser even when the pitch of the top feed dog is maximized. Then adjust the position of the horizontal shaft.

™ Rear constant

1) Make horizontal arm A 1 in the state of temporary tightening, turn the handwheel and adjust the top feed dog to the most retarded position.

2) At the position, tighten horizontal arm A 1 at the position where the top feed dog does not move even when the top feed lever is moved.

™ Front constant

1) Make horizontal arm A 1 in the state of temporary tightening, turn the handwheel and adjust the top feed dog to the most advanced position.

2) At the position, tighten horizontal arm A 1 at the position where the top feed dog does not move even when the top feed lever is moved.

(Caution) 1. Never loosen horizontal arm B 2 since it

keeps the thrust of the horizontal drive shaft.

2. Set horizontal arm C3 to the position where horizontal feed link 4 lightly moves without play.

3. Provide a clearance of 0.5 mm or more between the top feed dog and the groove of the presser when the pitch is maximized.

™ At the time of rear constant, the

lowest point of the top feed dog is apt to be lowered when increasing the top feed stroke (clearance between top feed and bottom feed dogs is increased) and there is no effect for partial shirring. Use the top feed dog with intermediate constant or front constant.

™ When the top feed dog is set to

front constant, biting of cloth at the start of sewing is improved. However, a few loading is apt to occur at the overlapped section of knit fabric

™ If the play between horizontal

arm C 3 and horizontal feed link 4 is large, the return of the top feed adjusting lever is worsened and a forcible load is applied to the components.

Page 58

−54 −

Standard Adjustment

(32) Position of the motion of the top feed dog

1. The position of motion is adjusted to rear constant for 50H and 60H series and MO-6900J, and to intermediate constant for other models at the time of delivery so that the best locus suitable to the purpose of use can be obtained.

2. Intermediate constant position at the time of delivery The position of motion of the top feed dog other than that of 50H, 60H and MO-6900J is adjusted to the position where the top feed dog does not move even when the top feed lever is moved at the position where the timing is advanced by 19˚ from the upper dead point of needle.

(33) Adjusting the feed bar guides A and B

When the play of the top feed dog in the lateral direction is excessively increased, the play can be removed by adjusting the feed bar guides A and B.

19˚

Upper dead point of needle

19˚

2˚

Approx. 10 mm

Hole on this side

Oil pan side

Page 59

−55 −

Adjustment Procedures Results of Improper Adjustment

™ Standard of the position where timing is advanced by 19˚from

the upper dead point of the needle

1) Timing is advanced by approximately 21˚ from the upper dead point of the needle at the position where the hole in the periphery of the handwheen faces just under.

1) Remove top cover, locus cut base, exhaust slot support, and adjusting arm spring.

2) Loosen top presser adjusting screw 1, top presser adjusting screw nut 8, release top presser pressure, and check the play in the lateral direction of top feed dog 2.

3) Remove the needle thread tank, loosen setscrew 3 in the feed bar guide B and temporarily tighten feed bar guide B 4 so that top feed bar 6 is put between feed bar guides B 4 and A 5.

4) Move top feed dog 2 up or down and adjust so that top feed dog 2 comes down by its weight and that the play in the lateral direction of top feed dog 2 is kept down to a minimum.

5) When jar is produced at top feed dog 2 and the top feed dog does not come down by its weight even after adjusting feed bar guide B 4, loosen setscrew 7 in the feed bar guide A and adjust feed bar guide A 5 at the same time. At this time, adjust the lateral position of top feed bar 6 to the position where top feed dog 2 drops naturally when moving it up or down several times.

6) Securely tighten the respective setscrews and check that there is neither play nor jar.

7) Return adjusting arm spring, exhaust slot support, locus cut base and top cover to their home places. Refer to “(27) Vertical stroke of the top feed dog”.

(Caution) When jar occurs between feed bar guide A 5 and B 4,

and top feed bar 6, jumping of top feed dog 2 will be caused. Adjust the top feed dog to such an extent that it comes down by its weight as mentioned above.

™ When the play in the lateral

direction of top feed dog 2 occurs, the top feed dog comes in contact with the presser and noise occurs or feed dog defect is apt to be put on cloth.

™ On the contrary, when torque

occurs between fedd bar guides A 5 and B 4, and top feed bar 6, inducement of the jumping phenomenon of top feed dog 2 will be caused.

Page 60

−56 −

Standard Adjustment

(34) Adjusting the top feed dog pressure

MO-6900R

MO-6900J

Dimension A

24 to 25mm

20.5 to 21.5mm

Vertical amount of top feed dog Less than 6.5mm

6.5 to 8.5mm

8.5mm

Max. sewing speed 7,000rpm 7,000rpm 6,000rpm

1. Standard is the position where the top feed dog stops jumping and, when further the screw is tightened, sound becomes quiet and is stabilized when gradually tightening the screw from the lower pressure. Besides, when using the top feed dog making low the top feed dog pressure, decrease the vertical amount of the top feed dog or decrease the sewing speed.

2. Dimensions listed in the list are slightly increased values that can be guaranteed even when the vertical amount of top feed dog and sewing speed are in the most strict combination in the list. Accordingly, when using the machine by decreasing the vertical amount of the top feed dog or decreasing the sewing speed, use it with rather large value (top feed dog pressure is low) than dimensions A in the list.

(35) Lifting amount of the top feed dog (when operating the pedal)

The height of the top feed dog from the top surface of the throat plate when the pedal is depressed at the lowest point of the needle bar and the top feed dog goes up to the highest point is 9 ± 0.5 mm.

In case of MO-6900J, the height is 10.5 ± 0.5 mm.

Top feed dog

Throat plate

9 ± 0.5mm

Page 61

−57 −

Adjustment Procedures Results of Improper Adjustment

Loosen top presser adjusting screw nut 1, when tightening top presser adjusting screw 2, the top feed dog pressure is increased and feed force is increased. After the adjustment, be sure to tighten top presser adjusting screw nut 1.

(Caution) When the top feed dog jumps and noise becomes

large during using the sewing machine, tighten top presser adjusting screw 2 until noise becomes small. When the machine is used for many hours while noise is excessively large, a forcible load is applied to other section. So, be careful.

1) Loosen lifter B stopper nut 1 and turn lifter B stopper screw 2 to adjust the lifting amount.

2) After the adjustment, tighten lifter B stopper nut 1.

<Checking after adjustment> Play between the top end of lifter B stopper screw 2 and presser lifting arm 3 should be 0.5 to 1 mm when the top feed dog is brought to the lowest point (needle bar is at highest point). (Top end of the screw should be separated from presser lifting arm 3 by 0.5 to 1 mm when pulling the lifter B with finger.)

™ When top feed dog pressure is

excessively low

Top feed dog jumps and noise

becomes large.

Feed force is decreased.

™ When top feed dog pressure is

excessively high

Feed dog defect is put on some

materials.

Unnecessary load is applied to

the sewing machine and the sewing machine is influenced for the worse by it.

Noise level is increased.

™ When the lifting amount of the

top feed dog is excessively high, contact occurs between vertical shaft and lifter B, and noise occurs when operating the sewing machine.

™ When the lifting amount of the

top feed dog is excessively low, when entering cloth at the start of sewing heavy-weight materials, cloth may be not able to be entered at the top feed dog.

Page 62

−58 −

Standard Adjustment

(36) Height of the presser (pedal operation)

Height of the presser from the top surface of the throat plate when the presser goes uo to the highest point

(Caution) When height A of the presser is adjusted at the time of operating the pedal, in

connection with it, the adjustment value of the lifting amount of the top feed dog is changed. Check the lifting amount of the top feed dog after adjusting the height of the presser referring to “(35) Lifting amount of the top feed dog (when operating the pedal)”

Height

of presser A (Max.)

6.5

5.5 ± 0.2

5.5 ± 0.2 5 ± 0.2 5 ± 0.2

6.5

6.5 8

Model

MO -6904R -0 4 -300

0 6 -300 0 4 -500

MO -6914R -B 4 -307

B 6 -307

MO -6916R -D 4 -300

D 6 -300 FF6 -300 F 6 -50H

F 6 -60H MO -6943R -1D6 -307 MO -6914R -B 6 -337 MO -6914R - -4 H Whole MO-6900J

–1

Throat plate

Level

Presser

(Unit : mm)

–1

Page 63

−59 −

Adjustment Procedures Results of Improper Adjustment

1) In the state that the presser pressure is applied, loosen presser turning lock nut 5 and adjust the height with presser lifter turning setscrew 4 so that the height in the list is obtained when operating the presser lifting pedal. At this time, check that there is no contact of the presser with upper looper, needle clamp, top feed dog, etc.

(Caution) Adjust the height so that there is a slight clearance

between presser arm 8 and presser arm stopper 9 when pedal is pressed and presser lifting arm 3 comes in contact with presser lifter turning setscrew 4 and stops.

™ Adjust the height by the procedure below even when presser

thrust arm 6 is removed.

1) Removing the thrust play of the presser shaft, temporarily tighten thrust arm clamping screw 7. Lower the presser by 1 to 3 mm from the throat plate with presser arm 8.

2) Next, in the state of the aforementioned 1), fix presser lifter arm 3 with thrust arm clamping screw 7 so that presser lifter arm 3 is level and there is no clearance at section A.

3) Adjust the lifting amount of the top feed dog with the aforementioned lifter B stopper screw 2 and nut 1, and adjust the height of the presser with presser lifter turning setscrew 4 and nut 5 so that the height in the list is obtained.

™ When the height of the presser

is excessively low, entering or taking out of cloth becomes hard.

™ When the height of the presser

is excessively high, there is the possibility that the presser comes in contact with upper looper, needle clamp, etc.

Page 64

−60 −

Standard Adjustment

(37) Lifting amount of the top feed dog (when the presser lifting lever is operated)

It is the standard that the height from the top surface of the throat plate is 9 ± 0.5 mm when presser lifting lever 5 is pressed at the lowest point of the needle bar and top feed dog 7 goes up to the highest point. MO-6900J : 10.5 ± 0.5 mm

Throat plate

9 ± 0.5mm

Page 65

−61 −

Adjustment Procedures Results of Improper Adjustment

1) Remove cloth base side cover 2 and top feed cover 1.

2) Bring the needle bar to the lowest point of its stroke and keep top feed dog 7 at the height of 9 ± 0.5 mm (MO-6900J : 10.5 ±

0.5 mm) from the top surface of the throat plate. (Insert the spacer between the throat plate and top feed dog 7.)

3) Loosen clamping screw 4 of lifter A 3.

4) Press presser lifting lever 5 until it will go no further and turn it. In this state, turn lifter A 3 and strike the pin section to the eaves section of top feed square block 6. Then tighten clamping screw 4 of lifter A 3.

(Caution) In the state that presser lifting lever 5 is returned,

check that there is a clearance between the pin of lifter A 3 and the eaves section of top feed square block 6.

5) Return top feed cover 1 and cloth base side cover 2 to their home positions.

™ When the lifting amount of top

feed dog 7 is excessively high, contact of top feed square block

6 with the pin section of liter A 3 occurs at the time of

operation and something is wrong with the machine.

™ When the lifting amount of top

feed dog 7 is excessively low, cloth or the presser becomes hard to be removed at the thick section such as overlapped section or the like.

Page 66

−62 −

Standard Adjustment

(38) Position of the thread guides and the looper thread take-ups

Needle thread

take-up

Needle

thread guide

The thread hole in the needle thread guide and the hooked portion of the needle thread take-up are in the position where 2/3 of the hole in the needle thread guide can be observed.

Needle thread take-up lever of 2-needle machine

Needle thread guide of 2-needle machine

The thread hole in the needle thread guide and the hooked portion of the needle thread take-up are in the position where 2/3 of the hole in the needle thread guide can be observed.

Needle thread guide

Needle thread take-up lever of doublechainstitch machine

Needle thread takeup guide of double-

chainstitch machine

The thread hole in the needle thread guide and the hooked portion of the needle thread take-up are in the position where 2/3 of the hole in the needle thread guide can be observed.

The thread hole in the double-chainstitch needle thread guide and the hooked portion of the needle thread take-up are in the position where the entire hole in the needle thread guide can be observed.

MO-6

04S (R) MO-6 14S (R) MO-6 16S (R)

(Caution) The needle thread take-up shall be positioned at the lower dead point.

Upper looper thread

guide (middle)

Upper looper thread guide (upper)

Upper looper thread guide (right)

Lower looper thread guide

Lower looper thread take-up

Looper thread

take-up (rigjt)

Looper thread

take-up (left)

MO-6

04S (R) MO-6 14S (R) MO-6 16S (R) MO-6 16S (R) MO-6 05S (R) MO-6 04S (R)

(Standard) (Standard) (Standard) (50H, 60H) (Hemming) (Soft chain)

Symbol

General

thread

Woolly

thread

General

thread

Woolly thread

General

thread

Woolly thread

General thread Woolly

thread

General thread

A 15.8 ,, ,, , , ,, 13.5 B

3.4 ,, ,1.8 , 2.6 3.4 , 2.1

- - - - 21.5 , 2.3 - - -

- - - - 30.5 , 24.5 - - -

22 ,, ,, , , ,, , F65,, ,, , , ,, , G 17.5 ,, ,, , , ,, , H 43.5 ,, ,, , , 40.5 , 43.5

I 26.5 ,, ,, , , 24 , 26.5

J384138, 34 36 34 38 42 43.5 K15, 12 15 12 15 12 12 , 14 L 6.5 , 10 , 6.5 ,, 24 34 , M29,, ,27.5 ,, 29 , 26.5 N272123, 20 , 19 24 , 19 O11,, ,, , , 12 , 9.5 P----16, 12.8 - - -

(Unit : mm)

General

thread

Page 67

−63 −

1) Perform the adjustment by the setscrews. Position of the needle thread guide 1 and needle thread take up 2 lever is a very important decisive factor when making soft chains since the needle thread take-up amount is increased in this case. So, carefully position these parts.

2) Set distance I a little smaller when using synthetic thread or the like which tends to form stitches swelling out of the cloth edge. A smaller I is effective for preventing stitch skipping.

3) Distance J is related to the vertical knotting point of the upper and lower looper threads. Set this distance larger for wooly thread, and set it smaller for thin thread which is likely to cause stitch skipping.

4) It is desirable to set distance K larger for stretchy threads such as wooly thread.

5) Set distance L a little larger when making blind hemming soft chain stitches.

6) Set distance N a little smaller for blind hemming or making soft chain stitches.

7) Set distance O larger if stitch skipping occurs due to looper thread slack. Set it smaller for better appearance and touch of produced stitches when wooly thread is used.

Adjustment Procedures Results of Improper Adjustment

™ Distance a

When set smaller, better tightness of needle thread stitches will be obtained. When set larger, loose needle thread stitches will result.

™ Distance E, F and H exert least

influence on stitch formation, however, improper setting of these distances will cause contact between the moving parts.

™ Distance J

When set larger, the amount of the upper looper thread will be increased. When set smaller, the amount of the upper looper thread will be decreased.

™ Distance K

When set larger, the amount of the upper looper thread will be increased. When set smaller, the amount of the upper looper thread will be decreased.

™ Distance L

When set larger, the amount of the upper looper thread will be increased. When set smaller, the amount of the upper looper thread will be decreased.

™ Distance N

When set larger, the amount of the upper looper thread will be increased. When set smaller, the amount of the upper looper thread will be decreased.

™ Distance I

When set larger, the amount of the upper and lower looper threads will be increased. When set smaller, the amount of the upper and lower looper threads will be decreased.

™ Distance O

When set larger, the amount of the upper and lower looper threads will be decreased. When set smaller, the amount of the upper and lower looper threads will be increased.

Needle

Needle thread take-up amount

Swell out

Lower looper

Thread slack

Upper looper

Thread slack

Upper looper

Small

Large

Page 68

−64 −

Standard Adjustment

(39) Adjusting soft chain making mechanism

1) Replacing the parts with those exclusively designed for making soft chains

1 Needle thread presser plate C.......12112504

2 Driving cam....................................12112603

3 Needle thread presser spring B.....12112702

4 Throat plate....................................(only for 1-needle

overlock machine)

0D4-300 .........................................R4200J6DD0A

2) Adjustment value

1 Needle thread guide and needle thread take-up lever

Adjust the needle thread guide to increase the needle thread feeding amount when the needle bar is in the lowest dead point of its stroke.

2 Adjust the rising amount of needle thread presser plate C.

Adjust the rising amount of needle thread presser plate C 1 to 0.6 to 1 mm (max.) by moving driving cam 2 to the right and left within the slot.

Rising amount : 0.6 to 1 mm (max.)

Cam face

(16 Safely stitch machine)

Cam face

Max. slot of the needle thread guide

Needle thread takeup amount when the needle bar is in its lowest dead point

3.1 to 3.6mm

(04 1-needle overlock machine)

Max. slot of the needle thread guide

Needle thread takeup amount when the needle bar is in its lowest dead point

2.5 to 3mm

Rising amount

Page 69

−65 −

3) Important points in adjustment

1 Increase the thread take-up amount of the needle thread take-up lever.

Refer to the adjustment values related to the needle thread guide and needle thread take-up lever.

2 Reduce the feed of the looper threads. (Mainly lower looper thread)

Set J, K, L and M for the soft chain distances. Fine adjustment of J and M is required to produce even stitches.

3 Adjsut the thread tension while checking the appearance and touch of the stitches produced.

1) Minimize the needle thread tension as far as satisfactory tightness of needle thread stitches is obtained.

2) Increase the upper looper thread tension as much as possible.

4 If the chain-off thread does not stretch satisfactorily, and if it is not satisfied, proceed with the

following.

1) Increase the upper looper thread tension.

2) Further increase distances J and K.

3) Further increase the upper looper thread tension.

4) Increase the lower looper thread tension to a maximum as far as good tightness of needle thread stitches is maintained.

5) Increase the thread take-up amount. If the needle thread is poorly tensed, increase the needle thread tension.

5 Fine adjustment for producing stitches with better appearance and touch

1) If the knotting point varies at high or low sewing speed, slightly reduce L, and increase the lower looper thread tension.

2) If a knot is made at a high point, increase J and I.

3) If the needle thread is likely to break, decrease the thread take-up amount and lower the needle thread tension.

6 Pay attention to the following

1) Minimize the needle thread tension as far as satisfactory tightness of needle thread stitches is obtained.

2) The knot of upper and lower looper threads should be made near the upper edge of a material.

3) Minimize the lower looper thread tension as far as even stitches are maintained.

4) For a safety stitch machine, adjust the soft chain making mechanism so that uniform chain-off thread is produced during double-chain stitching and overlocking.

The value given in ( ) parentheses is the adjustment value for the safety stitch machine. (Unit : mm)

Upper looper thread

guide (middle)

Upper looper thread guide (upper)

Upper looper thread guide (right)

Lower looper thread guide

Lower looper thread take-up

Looper thread

take-up (rigjt)

Looper thread

take-up (left)

17.5

9.5

Soft chain stitches

Standard stitches

Looper thread should not be loosened and stretch well

The looper thread loosens

When the chain-off thread is pulled.

33.5 (27)

26.5

26.5 (24)

43.5(36.5)

43.5

Page 70

−66 −

Standard Adjustment

(40) Position of the thread guides and the looper thread take-ups of MO-6900G(J)

(Caution) The needle thread take-up shall be positioned at the lower dead point.

MO-6904G (J) MO-6914G (J) MO-6916G (J)

MO-6903G MO-6905G

Frame

Needle thread

guide

4mm

The thread hole in the needle thread guide and the hooked portion of the needle thread take-up are in the position where 1/2 to the entire hole in the needle thread guide cannot be observed.

Frame

Needle thread guide

Needle thread take-up

Approx. 2 mm

14.8mm

Needle thread take-up of 2-needle machine

Frame

Needle thread

guide of 2-needle

machine

The thread hole in the needle thread guide and the hooked portion of the needle thread takeup are in the position where 1/2 to the entire hole in the needle thread guide cannot be observed.

Frame

Needle thread

guide

Needle thread take-up

10mm

2.5mm

Frame

Needle thread take-up of doublechainstitch machine

The thread hole in the needle thread guide and the hooked portion of the needle thread takeup are in the position where 1/2 to the entire hole in the needle thread guide cannot be observed.

16.5mm 15mm

3mm

1.8mm

15.8mm

Needle thread guide

Needle thread take-up

33mm

26mm

36mm

2.5mm

2mm

Page 71

−67 −

MO-6904G (J), 6914G (J), 6916G (J)

MO-6905G

MO-6903G

(Unit : mm)

(Caution) The upper looper thread-take-up (right)

and the looper thread take-up (left) shall be positioned at the extreme right point of the upper looper.

Position MO-6904G(J)-0F6-700 MO-6914G(J)-CH6-700 MO-6916G(J)-F 6-700 MO-6905G-0M6-7 0 MO-6903G-0N6-3D1

A70 ,,65 B22 ,,20 C48 ,,46 52 D18 ,,,, E43 ,,22 F22 ,,18 G11 ,,16 13 H27 ,,26 31

I23 ,,20 J18 ,,10 -

K17 ,,,27

Page 72

−68 −

4. ADDITIONAL INFORMATION AND PRECAUTIONS

(1) Thread tension

1) Strength of tension spring

Part No.

11550100 11550209 13137807 13138508 13138805

B3121804000

Color

Purple Green

Red

Yellow

Blue Gray

Natural length

(mm)

19.5 mm

17.8 mm

17.3 mm

13.8 mm

Operating

length (mm)

11.5 mm

9.8 mm

9.3 mm

5.8 mm

Weight required to compress spring to working length

8.92±0.49N (910 ± 50 g)

6.27±0.49N (640 ± 50 g)

4.21±0.49N (430 ± 50 g)

3.14±0.34N (320 ± 35 g)

1.47±0.20N (150 ± 20 g)

Where to use

Model

Needle thread Double-chainstitch

needle thread

Upper looper

thread

Lower looper

thread MO-6 04S(R) series Red – Yellow Blue MO-6 05S series Yellow – Blue Yellow MO-6 12S series Red Yellow – Yellow Blue

MO-6 14S(R) series Red Yellow – Blue Yellow MO-6 16S(R)- - (4 or lower) Red Yellow Yellow Blue MO-6 16S(R)- -50 Red Red Blue Yellow MO-6 16S(R)- -60H Green Green Blue Yellow MO-6 43S(R) series Red Red Yellow Blue Yellow MO-6 45S series – Red Red – – MO-6903G-0N6-3D1 Blue – – Blue MO-6904G(J)-0F6-700 Purple – Yellow Red MO-6905G-0M6-7 0 Yellow – Yellow Purple MO-6914G(J)-CH6-700 Red Yellow Yellow Red MO-6916G(J)-F 6-700 Purple Green Yellow Red

Nos.engraved on

upper looper *1188 81 1199 92 1217 62 *1217 60 120148 123835 123837 123836 123835

Model

6 04S(R) series 6 16S(R) series

6 14S(R) series 6903G-0N6-3D1

6904G(J)-0F6-700

6905G-0M6-7 0 6914G(J)-CH6-700 6916G(J)-F 6-700

Needle No.

(kind) #9 #11 #14 #14 #16 #18 #21

#16 (DOx5) #21 (DOx5) #24 (DCx1) #18 (DOx5) #21 (DOx5)

(2) Upper looper

Use a proper upper looper in accordance with the needle No. When ordering, refer to the Parts List. The numbers shown in frame in the table below are engraved markers. In addition, the letters in ( ) parentheses are the kinds of the needles.

Parts Nos. with an asterisk * are factory-installed on the standard machine heads at the time of delivery.

2) Springs used for each model.

Page 73

−69 −

(3) Center-to-center distance of the upper looper holder

The center-to-center distance of upper looper holder 1.

(Caution) * (asterisk) marks are exclusive for

to the MO-6900G(J). They are not common to the MO-6000S(R) series.

(4) Caution in assembly

1) Application of sealant

1 Setscrew of the throat plate base (B) retainer 2 (JUKI seal)

Apply the sealant only to the right setscrew.

2 Bottom surface of the upper looper guide support 3 (Three-bond 1104)

Apply the sealant to the bottom surface of the upper looper guide support 3, which contacts with the frame surface.

3 After assembling the front edge of the upper looper guide support 3 (Three-bond 1212), apply the

sealant to the gap of the contact surface between the frame and the upper looper guide support 3 ( section in the illustration).

Model

MO- 6 04S(R) - -

6 05S - - 0

MO- 6 04S(R) -

0D4 to 0E4

4 H

0F6 50H MO- 6 12S -CE4 -40H MO- 6 12S -D MO- 6 14S(R) - MO- 6 16S(R) - - 0

BE4

DD to FF

MO- 6943R - - 7 MO- 6 43S - -40H MO- 6903G -0N6 -3D1 MO- 6904G(J) -0F6 -700

700 7E0

MO- 6914G(J) -CH6 -700

FH6

FF6

Center-to-center distance H

38 39 39 38 39

39 39

*39

37.5 *39

37.5

MO- 6 16S(R)- -

MO- 6916G(J) - -700

Apply only to the right setscrew

Apply the sealant to the bottom surface.

234567

Frame

Be careful not to allow the

sealant to run to the rear.

Apply the sealant to

bottom surface.

(Unit : mm)

MO- 6905G -0M6 -

4 H 5 H

Page 74

−70 −

4 Portion of the setscrews of the dust-proof rubber case (JUKI seal)

Apply the sealant to the oil shield case setscrew 1 (1 pc.) and the dust-proof rubber case 2 setscrews (4 pcs.)

5 Oil shield plate assembly (JUKI seal)

Apply the sealant to the inside of the oil shield plate 3.

6 Portion of the feed mechanism cover (Three-bond 1212)

Apply the sealant to the rear face of the feed mechanism cover, the top surface of the oil shield plate, the oil shield rubber support plate , the top surface of the oil shield case, and the hatched parts on the top surface of the feed bar presser.

Apply the sealant to the hatched parts.

Lightly apply the sealant to the rear face of the feed mechanism cover and the top surface of the feed bar presser.

Apply the sealant to the

top surface of the oil

shield plate.

Apply the sealant to the frame.

Apply the sealant to the oil shield rubber support

plate and the top surface of the oil shield case.

Be careful that the sealant should not overflow on

the side of the oil shield rubber.

Feed mechanism

cover (rear face)

Inside contact surface

Page 75

−71 −

2) Precautions to be taken with respect to the lubricating components

Feed bar components

™ Be careful of the orientation of the oil shield rubber 4 and the dust-proof rubber 5.

™ Assemble the feed bar presser 6 and the dust-proof rubber case 2 so that their top faces are flush

with the frame plane on which the feed mechanism cover is installed.

™ Do not loosen the screws in feed bar presser 6 unless it is necessary. The clearance between the feed

bar presser and the feed bar and the contact with each other are important.

* Assembling as shown in the illustration will

result in oil leakage. So, be careful.

Do not loosen the screws.

7 Various sealants

JUKI exclusive part Nos. of the above 3 kinds of the sealants are not set.

Maker’s name Part No.

Three Bond 1104D * Three Bond 1104 Three Bond 1212

* : It is commonly called “JUKI seal”.

Page 76

−72 −

* Use a motor of 3/4 HP (550 W) when the sewing machine runs at 7,000 rpm or higher speed.

Use a motor of 1/2 HP (400 W) when the sewing machine runs at a speed lower than 7,000 rpm.

(Caution) If a motor of less than 400W is used, in the low tenperature area, viscosity of oil increases

and the sewing speed may not increase or the sewing machine may fail to run in some cases.

* Part No. of motor pulley

MTKP0xxx000 (Enter the effective diameter to “xxx.”) If the outside diameter of the motor pulley is 150 mm, the effective pulley will be 145.

.....So, the part No. will be MTKP0145000.

If the outside diameter of the motor pulley is 90 mm, the effective pulley will be 085.

.....So, the part No. will be MTKP0085000.

* Part No. of belt

MTJVM00xx00 (Enter a number that shows the belt length to “xx.”) If the belt length is 1016 mm (40 inches), enter “40” to “xx.”

.....So, the part No. will be MTJVM004000.

If the belt length is 889 mm (35 inches), enter “35” to “xx.”

.....So, the part No. will be MTJVM003500.

(5) Kinds of motor pulleys, belts and frame support plate bolts

1) Motor pulleys and belts

MO-6 00S(R)

MO-6900G(J)

Sewing speed of sewing machine (rpm)

8500 8000 7500 7000 6500 6000 5500 5000 4500 4000

50 Hz

160 (155) 150 (145) 140 (135) 130 (125) 120 (115) 110 (105)

100 (95)

90 (85) 85 (80) 75 (70)

Semi-sunken type mm (inch)

1016 (40) 1016 (40)

965 (38) 965 (38) 965 (38) 914 (36) 914 (36) 889 (35) 889 (35) 864 (34)

Fully-sunken type mm (inch)

914 (36) 864 (34) 864 (34) 864 (34) 813 (32) 813 (32) 813 (32) 762 (30) 762 (30) 762 (30)

60 Hz

135 (130) 125 (120) 120 (115) 110 (105)

100 (95)

95 (90) 85 (80) 80 (75) 70 (65) 60 (55)

Semi-sunken type mm (inch)

965 (38) 965 (38) 965 (38) 914 (36) 914 (36) 889 (35) 889 (35) 864 (34) 864 (34) 864 (34)

Fully-sunken type mm (inch)

864 (34) 813 (32) 813 (32) 813 (32) 813 (32) 762 (30) 762 (30) 762 (30) 762 (30) 737 (29)

V-belt

Sewing speed of sewing machine (rpm)

6000 5500 5000 4500 4000

50 Hz

125 (120) 115 (110) 105 (100)

95 (90) 85 (80)

Semi-sunken type mm (inch)

965 (38) 940 (37) 914 (36) 914 (36) 889 (35)

Fully-sunken type mm (inch)

864 (34) 838 (33) 838 (33) 813 (32) 787 (31)

60 Hz

105 (100)

95 (90) 85 (80) 80 (75) 70 (65)

Semi-sunken type mm (inch)

914 (36) 914 (36) 889 (35) 889 (35) 889 (35)

Fully-sunken type mm (inch)

838 (33) 813 (32) 787 (31) 787 (31) 787 (31)

V-belt

Outside diameter of motor pulley mm (Effective diameter mm)

Page 77

−73 −

2) Pat No. of frame support plate bolt

1 Semi-sunken type Support plate bolt (A) 13155007 x4 Locknut NS6240630SE x4 Washer WP1002036SE x4 Spring washer WS1002560KR x4

2 Fully-sunken type Support plate bolt (C) 13155106 x2 Support plate bolt (D) 13155205 x2 Locknut NS6240630SE x12 Washer WP1002036SE x12 Spring washer WS1002560KR x4

Difference of support plate bolts (A), (C) and (D) Entire length under the neck and length of threaded part

Entire length Length of threaded part Support plate bolt (A) 69 39 Support plate bolt (C) 137 107 Support plate bolt (D) 149 119

69 mm

39 mm

137 mm

107 mm

149 mm

119 mm

Support plate bolt (A) Support plate bolt (C) Support plate bolt (D)

1. When the sewing machine is used for many hours, cartridge filter 1 may be clogged with dust. When this state continues, oil is not fed through cartridge filter 1 and abnormal worn-out or seizure of the sewing machine will be caused. * Normally, be sure to check cartridge filter 1 every 6 months,

and clean or replace it.

2. Inspecting/replacing procedure

1) First, remove drain screw 2.

2) Remove setscrews 3 and remove upper cover 4 toward right above.

(Caution) When upper cover 4 is moved in the lateral direction,

the oil amount indicating rod or the filter may be damaged.

3) Remove and inspect cartridge filter 1. If cartridge filter 1 is clogged with dust, clean it or replace it with a new one.

4) Insert cartridge filter 1 in place and install upper cover 4 with setscrews 3.

* Part No. of cartridge filter : 11843208

(6) Inspection and replacement of the cartridge filter

(Unit : mm)

Page 78

Page 79

– 74 –

5. ADJUSTMENT OF THE NEEDLE HEIGHT AND LOOPER TIMMING

(1) MO-6000 SERIES

13131008 13131107 11582012 12375507

Upper looper

holder

39 37.5

13131909 13132006 11545100 12375606

Upper

looper guide

support

gauge

4.0

5.5

4.7

6.3

5.8

4.2

2-needle

(right)

Upper looper

height

Projection of upper looper

Height of pin

Position of

guide support

Center-tocenter of upper looper holder

Feed amount of lower looper

Radius of

lower looper

Feed amount

of double-

chain looper

Radius of

double-chain

looper



10.5±0.1 – 11.0±0.3 4.0±0.3 (45.0) A 13222203 38 #81 4.0 66.9– – Marker (11888609)

10.5±0.1 – 11.0±0.3 4.0±0.3 (46.2) A 13222203 38 #81 3.7 66.9 – –

A (11888609)

11.3±0.1 – 11.3±0.3 4.4±0.3 (48.2) A 13222203 39 #19 3.8 66.9 – –

A (11991908)

14.4±0.1 – 13.7±0.3 5.1±0.3 (48.8) A 13224001 37.5 #123835 3.5±0.5 66.9 – –

(12383501)

15.4±0.1 – 13.6±0.3 5.4±0.3 (51.2) A 13224001 39 #120148 1.4±0.3 66.9 – –

(12014817)

15.4±0.1 – 12.0±0.3 6.5±0.3 (51.7) A 13224001 39 #123837 1.3±0.3 66.9 – –

(12383709)

10.5±0.1 (9.1) 10.3±0.3 4.4±0.3 (47.3) B 13222302 39 #60 3.8 66.9 – –

B (12176004)

11.3±0.1 (9.9) 11.0±0.5 4.8±0.3 (48.4) A 13222203 39 #61 3.8 66.9 – –

A (12176103)

14.1±0.1 (12.6) 12.9±0.3 6.2±0.3 (49.3) A 13224001 37.5 #123836 3.3±0.5 66.9 – –

(12383600)

11.3±0.1 (9.9) 11.8±0.3 3.6±0.3 (46.8) A 13222203 38 #61 4.0 66.9 – –

A (12176103)

11.0±0.1 (9.4) 11.0±0.5 3.8±0.3 (46.9) B 13222302 39 #60 2.2±0.3 66.9 – –

B (12176004)

11.0±0.3 (9.4) 11.0±0.5 3.6±0.3 (46.9) B 13222302 39 #66 2.2±0.3 66.9 – –

B (11996600)

10.5±0.1 – 11.0±0.3 4.0±0.3 (46.2) A 13222203 38 #81 3.7 66.9 1.5 to 2.0 63.4

A (11888609)

10.5±0.1 – 11.0±0.3 4.0±0.3 (46.2) A 13222203 38 #92 3.7 66.9 1.5 to 2.0 63.4

A (11999208)

11.3±0.1 – 11.3±0.3 4.4±0.3 (48.2) A 13222203 39 #19 3.8 66.9 1.5 to 2.0 63.4

A (11991908)

13.0±0.1 – 12.8±0.3 4.7±0.3 (48.4) A 13222203 39 #62 2.8 66.9 1.5 to 2.0 63.4

A (12176202)

14.1±0.1 – 13.4±0.3 5.1±0.3 (48.8) A 13224001 37.5 #123835 3.5±0.5 66.9 1.7 ± 0.3 63.2

(12383501)

10.5±0.1 (9.1) 10.3±0.3 4.4±0.3 (47.3) B 13222302 39 #60 3.8 66.9 – –

B (12176004)

11.3±0.1 (9.9) 11.0±0.3 4.8±0.3 (48.4) A 13222203 39 #61 3.8 66.9 1.5 to 2.0 63.4

A (12176103)

9.8±0.1–––––––––––2.0 to 2.5 63.6

Description

Subclass

Needle height Upper looper components Lower looper components Double-chain looper

1-needle 2-needle

(left)

A B

(Right side)

Classification 1-needle overlock machine 2-needle overlock machine Safety stitch machine

Needle height Upper looper components Lower looper components Double-chain looper components

Marker of

guide support

Guide support cover

Marker of

upper looper

holder

+0.5 –0.8

+0.5 –0.7

+0.5 –0.8

(Right side)

+0.5 –0.7

+0.5 –0.8

+0.3 –0.7

+0.5 –0.8

6.3

5.8

4.2

4.0

5.8

4.2

4.7

5.5

6.3

5.8

4.2

5.8

1- needle overlock

macine/

safety stitch

machine

2- needle

overlock machine

3-needle

safety stitch

2-needle overioc machine 3-needle safety stitch machine

0A5 to 0F5 15

MO- - 0A4 to 0E4 -210

0D6 3 0F4 300

0F6 500 0H4 50M

0D4 to 0E4

MO- 6

04S - 0F6 -4 H

50H

MO- 6904G(J) -0F6 -700

MO- 6903G -0N6 -3D1

700 7E0

BD4 to BE4 BD6 to BE6

to BF 20H

BE7 4

MO- 6

14G(J)- CH6 -700

MO- 6

12S- CE4 -40H

MO- 6

12S- DF6 -507

MO- 6

12S- DF6 -50F

MO- 6

16S(R)- -3 0

MO- 6

16S- -500

BE4 DD

to F - 4 H

50H

MO- 6

16S(R)- F 6 -60H

MO- 6916G(J)- F

6 -700

MO- 6916R- 1D6 -307

MO- 6

43S- 1D6 -40H

MO-6

45S- ED4 -360

MO- 6905G -0M6 -

MO- 6

14S(R)- -3 7

MO- 6

14S(R)- -

04S(R)

05S

MO- 6

04S(R) - -

+0.5 –0.8

MO- 6 16S(R)-

Page 80

−75 −

6. TROUBLES AND CORRECTIVE MEASURES

Trouble Case (1) Case(2) Check and Corrective measures Page

1. Needle thread breakage Threading

Thread path

Needle guard

Needle

Needle heat

Thread

Thread tension

Contact

Double thread hooking (only for double chain stitch)

Deffective double chain-off thread (only for double chain stitch)

Threading

The thread is entangled with the thread guide, or the machine head has been incorrectly threaded.

Scratches, burrs or rust on the pawls or needle holes of the throat plate, stitch tongue, lower looper, double chain looper, needle thread take-up, needle thread presser spring, thread guide, or tension discs causes friction.

The needle hits the needle guard intensely, and sharp edges are produced on them, causing thread breakage.

The needle is too thin for the thread.

The needle gets very hot, depending on the type of materials, number of plies and sewing speed, and causes the thread to burn and break.

The thread is weak because of its poor quality.

The thread tension is too high.

The double chain looper or lower looper has been improperly positioned and strikes the feed dog or throat plate.

Poor drawing up of the needle thread causes the looper to catch it again.

Refer to the clause referring to defective double chainoff thread.

The thread is entangled with the thread guide, or the looper has been incorrectly threaded.

Refer to the threading diagram.

Remove such scratches, burrs, etc. and perform thread path finishing. Replace major components such as looper, which have been deformed, causing thread breakage.

Replace the needle and needle guard if they have worn,

Replace the needle by a proper one.

Use a thinner needle. Reduce the sewing speed. Use the needle cooler. Use an S-point needle or needle for synthetic thread.

Replace the thread by one with good quality.

Reduce the thread tension. Check whether the needle thread take-up guide and needle thread guide are positioned too high, causing such excessive thread tension.

Properly position the double chain looper or lower looper.

Increase the needle thread tension. Properly position the thread cam. Properly position the double chainstitch thread guide.

Refer to the treading diagram.

12, 20

Page 81

−76 −

Trouble Case (1) Case(2) Check and Corrective measures Page

2. Looper thread breakage

3. Needle breakage

Thread path

Adjustment of the looper thread take-up

Thread tension

Thread

Position of the thread guides

Double chain looper avoid (only for double chain stitch)

Needle heat

Needle entry

Upper looper position

Contact with the looper

Scratches, burrs, rust, etc, on the paw of the throat plate, stitch tongue, looper, looper thread take-up, thread guide, or tension discs causes friction.

The looper thread take-up or thread guide has been improperly positioned, causing excessive thread tension.

The looper thread tension is too high.

The thread is weak because of its poor quality.

The upper looper thread guide is too high, and the thread taking balance is disturbed, resulting in the thread breakage.

The double chain looper strikes the needle at the back, causing the thread breakage.

The needle gets hot, and the looper thread breaks when it comes in contact with the hot needle at the time of needle stop.

The needle entry has not been correctly adjusted, and the needle strikes the throat plate or presser foot.

The upper looper juts out too much or it is too low.

The needle strikes the looper, resulting in needle breakage.

Remove such scratches, burrs, etc. and carry out thread path finishing. Replace loopers or other components which have been deformed, causing thread breakage.

Refer to the pertinent Standard Adjustment.

Reduce the tension while checking the tension balance other looper thread.

Replace the thread by one with good quality.

Refer to the pertinent Standard Adjustment.

Correct the longitudinal motion of the double chain looper so as not to cause the looper to strike the needle.

Refer to the clause relating to the needle heat causing needle thread breakage.

Correct the needle entry.

Refer to the related Standard Adjustment.

Re-position the looper so that it does not come in contact with the needle. Adjust the longitudinal motion of the double chain looper for the contact of its back with the needle.

to the next page

Page 82

−77 −

Trouble Case (1) Case(2) Check and Corrective measures Page

From the previous page

Needle guards

Needle No.

Thread tension

Height of the feed dog or needle

Needle guard

Contact with the looper

Lower looper

Adjustment of the loopers.

Needle thread presser

Needle

Needle guards

4. The needle point is crushed. (Double chain stitch needle)

5. Overlocking needle thread stitches are skipped.

A needle guard has been improperly positioned, causing the needle point to strike it.

The needle is too thin for the materials.

The thread tension is too high.

The feed dog is too high, or the needle is too low, causing the needle to deflect with resultant needle breakage.

The needle guard C is too low, or its longitudinal position is not correct.

The tilt of the looper is not correct. The longitudinal motion of the looper is not correct.

The blade point has defective shape and does not catch needle thread loops.

The clearance or the amount of return is not correct.

The duration in which the presser holds the needle thread is not correct, and unstable loop result.

The needle is bent or improperly oriented. A needle or DC x 1 is used.

Incorrect height or clearance prohibits correct guide for the needle. If a needle guard is too high, loops are crushed with consequent stitch skipping.

Refer to the pertinent Standard Adjustment.

Replace the needle with a thicker one.

Reduce the thread tension.

Refer to the related Standard Adjustment.

Increase the height of the needle guard (C). Check the clearance between the needle and needle guard.

Check the tilt of the looper. Correct the longitudinal motion of the looper, and increase the clearance between the looper and needle when the looper reaches its most retracted position.

Replace the lower looper.

Refer to the relevant Standard Adjustment.

Refer to the pertinent Standard Adjustment.

Replace the bent needle. Correctly orient and attach the needle. Use a DC x J27 needle for a stretchy thread.

Refer to the pertinent Standard Adjustment.

Right side Wrong side

to the next page

The lower looper fails to catch needle thread loops.

8, 24

Page 83

−78 −

Trouble Case (1) Case(2) Check and Corrective measures Page

Right side Wrong side

From the previous page

6. Lower looper stitches are skipped.

Height of needle

Needle heat

Positioning of the needle thread take-up guide and needle thread guide

Threading

Upper looper

Lower looper

Adjustment of the loopers

Thread amount

The needle has incorrect height and does not properly pick up loops even if the looper has a correct return.

Stitch skipping occurs before the thread breaks due to needle heat.

They are positioned too high, and the needle thread take-up takes too much thread, producing too small loops.

The thread has been entangled with a thread guide. The reading has bot been correctly done.

The thread has been entangled with a thread guide. Threading has not been done correctly.

The blade point has a bad shape, and fails to catch the loops.

The clearance between the needle and the back of lower looper are not correct.

The feed amount of the lower looper, height of the upper looper, or clearance produced at time of crossing of the upper and lower loopers is not correct.

Too much lower looper thread is fed, giving slack of thread.

Refer to the related Standard Adjustment.

Refer to the clause relating to the needle thread breakage due to needle heat.

Refer to the pertinent Standard Adjustment.

See the threading diagram.

Refer to the threading diagram.

Replace the upper looper with badly deformed blade point.

Replace the lower looper having a deformed tip.

Refer to the relevant Standard Adjustment.

Slightly lower the looper thread take-up (left) (reduction in distance J), or slightly reduce distance I to decrease the amount of thread.

Slightly raise the looper thread take-up (right) (increase in dimension O) to decrease the amount of thread. Lower the lower looper thread guide (increase in distance L), and decrease distance N to reduce the amount of thread.

The upper looper does not catch the lower looper thread.

8, 12

12, 18

Page 84

−79 −

Trouble Case (1) Case(2) Check and Corrective measures Page

7. Upper looer thread stitches are skipped.

8. Double chain stitches are skipped.

Two stitches are skipped.

Threading

Needle height

Needle

Adjustment of the upper looper.

Amount of thread

Needle height

Needle

Double chain looper

The thread has been entangled with a thread guide. Threading has not been done correctly.

The needle, if positioned too high or low, may fail to catch the upper looper thread.

The needle is bent or crushed, in its point.

The height of the blade point is not correct, making the upper looper unable to properly pass the thread to the needle. The clearance between the needle and the back of the upper looper is not correct.

Excessive upper looper thread is fed, producing stack of thread.

If the needle is not correct, stitch skipping occurs even when the return of the chain looper is correct.

The needle is bent or attached with wrong orientation. A DC x1 needle is used.

The lower part of the blade point has been deformed, and the blade point fells loops.

See the threading diagram.

Refer to the related Standard Adjustment

Replace the needle. At this time, be sure to eliminate the cause for such needle bend or needle point crush.

Refer to the relevant Standard Adjustment.

Slightly lower the looper thread take-up (left) (reduction in distance J), or slightly reduce distance I to decrease the amount of thread. Make the upper looper thread guide (right) (shprter decrease in distance K), to reduce the amount of thread.

Slightly raise the looper thread take-up (right) (increase in dimension O) to decrease the amount of thread.

If the thread tension is not enough, increase it.

Refer to the pertinent Standard Adjustment.

Replace the bent needle. (Remove the cause for the needle bend.) Correct the orientation of the needle. Use a DC x27 needle (with a better recess configuration).

Replace the double chain looper.

Slack of thread

to the next page

The needle does not take the upper looper thread.

Lower looper

thread

Needle

Right side Wrong side

Upper looper

The double chain looper tails to catch needle thread loops.

Needle

Viewed from the wrong side

Needle

8, 18

Page 85

−80 −

Trouble Case (1) Case(2) Check and Corrective measures Page

9. Triangle double chain looper thread stitches are skipped.

Adjustment of looper

Thread tension

Needle guards

Needle heat

The needle point is crushed.

Double chain looper

Adjustment of looper

Thread cam timing

Thread tension

Threading

From the previous page

Clearance or returning amount is not correct.

The thread tension is too high, preventing formation of good loops.

A needle guard is too high, and loops are crushed. The clearance is too big, causing the needle to shake.

The thread breaks due to heat generated on the needle, depending on the type of materials, number of plies, and sewing speed.

The needle point has been crushed and got thicker and shorter.

The thread hole in the tip has worn, and the looper thread does not reach the needle as shown at right.

Excessive return or longitudinal motion will often cause this stitch skipping.

The thread cam timing is too early, causing the looper thread to slack before the needle enters a thread triangle.

The lower thread tension is very low, and the thread is not stretched.

The area around the thread cam has threaded erroneously.

One stitch is skipped.

Refer to the related Standard Adjustment.

Reduce the tension. However, be careful not to reduce the tension too much, othrewise unstable loops will result.

Refer to the relevant Standard Adjustment.

Use a thinner needle. Reduce the sewing speed. Check the coolant if necessary.

Refer to the clause relating to the needle point crush.

Replace the double chain looper.

Refer to the pertinent Standard Adjustment.

Increase the thread tension a little.

Correct the threading.

Needle Viewed from the

wrong side

The needle fails to catch the double chain looper thread.

Page 86

−81 −

Trouble Case (1) Case(2) Check and Corrective measures Page

Double chain looper

Adjustment of looper

Thread tension

Stitch length

Needle guard

Double-chain stitch needle thread guide.

Position of the throat plate

Feed dog

Adjustment of looper

Thread tension

The chain looper is too high and too close to the throat plate, or has bad shape.

The return is not enough, causing the needle to miss the loop.

The needle thread tension is too low.

The stitch length is as small as 1.5 mm or less.

A needle guard is too high, and catches needle thread loops.

The needle thread guide is installed too high, and it fails to tense the thread.

The throat plate has been improperly positioned longitudinally, and chain-off thread gets in between the main feed dog and throat plate, causing defective chainoff thread.

The auxiliary feed dog has scratch.

The auxiliary feed dog is too high, and interferes with chain-off thread. The auxiliary feed dog is too low. (Lower than the main feed dog by more than 0.5 mm)

Adjustment of loopers for producing chain-off thread without materials requires higher accuracy.

The thread tension is too low.

The needle thread tension is too high, causing damaged balance with other thread tension.

Correct the height of the chain looper by pushing it down until it cones into contact with the stopper. Replace the chain looper having a bad shape.

Refer to the related Standard Adjustment.

Slightly increase the needle thread tension.

Slightly increase the stitch length.

Adjustment of loopers for producing chain-off thread without materials requires higher accuracy than that with materials.

Refer to the related Standard Adjustment.

Correctly position the throat plate.

Repair or replace the auxiliary feed dog.

Refer to the pertinent Standard Adjustment.

Refer to the related Standard Adjustment.

Slightly increase the tension.

Check whether the needle thread take-up guide or needle thread guide is positioned too high with consequent excessive needle thread tension. And if so, correct it.

The needle thread extends to the adjacent stitch.

The needle fails to catch the needle thread loop on the double chain looper, resulting in the stitch skipping shown below.

Defectively interlaced loop

Needle thread

10.Triangle double chain needle thread stitches

are skipped.

11.Overlocking chain-off thread is bad.

Provided that no chain-off trouble occurred when sewing operation was done with materials set on the machine.

Page 87

−82 −

Trouble Case (1) Case(2) Check and Corrective measures Page

12.Problems with double chain stitch chain-off

thread.

Adjustment of loopers

Needle Guard

Position of the throat plate

Throat plate

Presser foot

Main feed dog

Double hooking

Thread tension

Refer to the related Standard Adjustment.

Correctly position the throat plate.

Repair or replace the throat plate, since such dent causes chain-off thread to slip out.

Replace it, or correct it to make it flush with the presser foot sole.

Buff the leading edge of the main feed dog.

Refer to the related Standard Adjustment for the return of the double chain looper. See the threading digram for correct threading.

Retard the cam timing.

Reduce the needle thread tension.

Slightly increase the both tensions.

Adjustment of the loopers for producing chain-off thread without materials requires higher accuracy.

The needle guard (C) is too high, damaging loops.

The needle comes into contact with the front edge of the needle hole in the throat plate.

The lateral position of the throat plate with respect to the feed dogs is wrong, causing chain-off to drop in.

A dent exists on the flat part between the rear edge of the needle hole and feed dog groove.

The rear pressure foot is indented and not flush with the presser foot sole, so that it cannot hold chain-off thread.

The leading edge of the main feed dog is too sharp and cuts chain-off thread.

The needle thread is not drawn up fully because of the insufficient return of the double chain looper or wrong threading.

If the feed pitch is too small, the cam timing will be advanced.

The needle is bend or chain-odd thread runs back due to excessive needle thread tension.

Both the needle thread and looper thread tension are too low.

Dent

20, 32

Page 88

−83 −

Trouble Case (1) Case(2) Check and Corrective measures Page

13. Overlocking needle thread is loose.

14. Double chain stitch needle thread is loose.

15. Uneven overlocking stitches

The knotting position of the upper and lower looper threads varies as shown below.

Position of the needle thread take-up guide and needle thread guide

Thread tension

Needle

Thread tension

Thread cam

Needle

Double-chain stitch needle thread take-up guide

Looper thread tension

Looper thread take-up

Knife width

Thread path

Presser foot

Thread stand

They are positioned too high, and the thread take-up draws out excessive needle thread.

The thread tension balance has been disturbed.

The needle is too thin for the thread used.

The looper thread tension is too high, and the needle thread tension is too low.

The thread cam draws out an insufficient amount of thread.

The thread cam timing is bad.

The needle is too thin for the thread used.

Drawing amount of the needle thread is insufficient.

The upper and lower looper thread tensions are not enough.

The looper thread take-up (left) is too high.

The knife width is unsuited for the overedging width.

Scratches on the thread path catch thread.

The presser foot cones into contact unevenly with the throat plate and feed dogs and tends to meander.

Thread dose not come out smoothly.

Refer to the pertinent Standard Adjustment.

Refer to the Standard Adjustment for the looper thread take-up components, and increase the tension if necessary.

Replace it with a proper one.

Reduce the looper thread tension to a minimum, and increase the needle thread tension.

Refer to the relevant Standard Adjustment.

Replace the needle with a proper one.

Refer to the relevant Standard Adjustment.

Slighrly increase the upper and lower looper thread tensions.

Slightly lower the looper thread take-up (left)

Make the overedging width slightly smaller than that given for the knife width.

Check the thread path for scratches.

Make the presser foot come into contact with them evently.

Make the thread come out smoothly.

Page 89

−84 −

Trouble Case (1) Case(2) Check and Corrective measures Page

16.Uneven double chain stitches

17.The looper thread bulges out

18.Looper thread bite

19.Knotting position is not correct.

Thread tension

Presser foot

Knife width

Looper thread take-up adjustment

Knife width

Adjustment of the looper thread take-up

Threading

Adjustment of the looper thread take-up

Slightly increase the tension.

Make the presser foot come into contact with the throat plate evenly.

Increase the presser foot pressure.

Use a knife having width suited to the overedging width.

Decrease the radius of the looper thread take-up (left) (reduction in dimension I). Raise the looper thread takeup (right) (increase in distance O).

Use a knife having width suited to the overedging width.

Increase the radius of the looper thread take-up (left) (increase dimension I). Lower the looper thread take-up (right) (reduction in distance O).

See the threading diagram.

Raise the looper thread take-up (left) to increase the amount of upper looper thread, and the knotting position moves toward the lower looper side.

Increase distance K.

The looper thread tension is not enough.

The presser foot comes into contact with the throat plate unevenly.

The presser foot pressure is not enough.

The knife width is too small for the overedging width.

The looper thread take-up draws out excessive looper thread.

The knife width is too large for the overedging width.

The looper thread take-up draws out insufficient amount of looper thread.

Re-threading after thread breakage,etc. has been done erroneously.

The height of the looper thread take-up (left) is not correct.

The upper looper thread guide (right) is too short.

Knots are deflected to the upper looper side.

Right side

Page 90

−85 −

20. Uneven material feed

21. Puckering

(Mainly concerned with double chain stitch)

Trouble Case (1) Case(2) Check and Corrective measures Page

Presser foot pressure

Presser foot

Tilt of feed dogs

Height of feed dogs

Adjustment of differential feed

Needle

Thread

Thread tension

Throat plate

Thread cam timing

Feed dogs

The presser foot pressure is too high.

The hinge is too stiff.

Scratches on or defective finish on the presser foot sole produce friction between the presser foot and materials.

The front is too high.

A different in level exists between the main feed dog and differential feed dog.

The differential feed has been improperly adjusted.

The needle is too thick.

The thread used is too thick.

Both the needle thread and looper thread tensions are too high.

The throat plate has a large needle hole.

The thread cam timing is too late.

The leading edge of the feed dog teeth has been rounded off.

A difference in level exists between the main feed dog and differential feed dog.

Reduce the presser foot pressure except for the uneven material feed due to packering.

Remove the stiffness provided no hinge play is produced.

Buff the presser foot sole for good surface finish.

Make the front down. However, be sure to align the differential feed dog with the main feed dog.

Eliminate the difference in level.

Provide differential feed suited to the material.

Use a thin needle as much as possible.

Reduce the both thread tensions to a minimum.

Replace the throat plate with one with a small needle hole.

Advance the cam timing. Refer to the related Standard Adjustment.

Replace the feed dog.

Eliminate such difference in level.

to the next page

Page 91

−86 −

Trouble Case (1) Case(2) Check and Corrective measures Page

From the previous page

Increase the presser foot pressure.

Set it for stretching. When stretching light-weight materials, be careful not to cause the presser foot to contact unevenly with the materials.

Bring the thread cam thread guide fully to the front to increase the amount of looper thread.

Presser foot pressure

Differential feed ratio

Thread amount

The presser foot pressure is not high enough, providing poor ironing effect.

The differential feed ratio has been set for gathering.

The looper thread amount is not enough, causing excessively tensed stitches.

26,28

Page 92

− 87 −

7. DIMENSIONS OF TABLE

(1) Semi-sunken type

Part No. of table : 11959400

130

1200

54±1

159±1

297

339

291±1

272±1

445 49

577±114

401125±1

40125

130(806)

500500

600

5021

100

(ø26)

(ø10)

(ø26)

(ø8.5)

37.5

0.57.5

11.5

7.5

0.8

0.811

5x160=800

5-R1

120˚

Detailed measurement

Type : Helvetica Reg. Condensed

Condensed voided letters

Thickness : 1.5

Thickness : 0.8 Thickness : 0.5 Thickness : 1.5

(380)

120

570

42±1

124

281±1

219±1

37.5

210

116

113±1

203.5

446

390

R30

R15

R10

R30

R15

R10

R15

R10

R15

R30

30˚

R15

R30

Drilled hole 17

3-8.5 hole, with 26 x 1

deep groove

4-10 hole, with 26 x 1

deep groove

This plane is finished

in the method same as

the outside wood.

Leg installing position

Push button switch installing position

Drawer stopper installing position (Rear)

Top of table

Drawer installing

position

This plane is finished

in the method same as

the outside wood.

Section W-W Section Z-Z Section Y-Y Section V-V

(Note) All dimensions are in millimeter.

Detailed dimensions of section W-W, section Z-Z, section Y-Y and section V-V

66.5±1

JUKI logotype

450

Applicable models

MO-6000 Series

158

R35

R24

R10

R15

(26)

Page 93

− 88 −

(2) Fully-suken type

1200

54±1

159±1

277

252

184

400±1150

319

42±1

308

437±1

(426)

107

125

150

(806)

201

350

290

50 78

(ø26)

(ø8.5)

ø26

(ø10)

570

(380)

120

400

160103

375

84 281±1

337±1

446

385

223±1

369

113±1203.5

160110

66.5±1

2.5

2 (14)

(1)

(4)

R30

R15

R10

R30

R10

R16

R34

R15

R10

R28

R30

30˚

R15

Drawer stopper installing position (Rear)

4-10 hoke 26 spot face 4 deep

3-8.5 hole, with 26 x 1

deep groove

Drilled hole 17

Leg installing position

Push button switch installing position

Drawer installing

position

Location of silk screening on the table surface

Concealed hinge

Clamp

Lid support plate

Screw

Top of table

JUKI logotype (silk screening)

Brand label location indicating of drawing

Section Z-Z

Section Y-Y Section X-X

425

(Note) All dimensions are in millimeter.

Part No. of table : 11959558

Applicable models

MO-6000 Series

Page 94

Please do not hesitate to contact our distributors or agents in your area for further information when necessary.

＊ The description covered in this engineer's manual is subject to change for improvement of the

commodity without notice.

02 · 10 Printed in Japan (E)

INTERNATIONAL SALES H.Q.

8-2-1, KOKURYO-CHO, CHOFU-SHI, TOKYO 182-8655, JAPAN

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