JUKI MO-6700D, MO-6704D, MO-6714D, MO-6716D Series Manual

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40033638

No.E368-00

ENGINEER’S MANUAL

HIGH SPEED SEMI-DRY HEAD OVERLOCK/INTERLOCK/ SEWING MACHINE

MO-6700D Series

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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 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”.

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CONTENTS

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

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

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

3. ST ANDARD ADJUSTMENT .......................................................................... 4

(1) Adjusting the needle height.......................................................................................4

(2) Positioning the throat plate .......................................................................................4

(3) Installing position of the needle clamp ....................................................................6

(4) Adjusting the length of the lower looper holder

(Applicable only to MO-6716D series) ......................................................................6

(5) Adjusting the lower looper ........................................................................................8

1) Returning amount of the lower looper ..................................................................................................8

2) Clearance between the lower looper and the needle...........................................................................8

(6) Position of the upper looper guide .........................................................................10

(7) Positioning the upper looper holder.......................................................................12

(8) Positioning the upper looper...................................................................................14

1) Height of the upper looper..................................................................................................................14

2) Longitudinal position of the upper looper ...........................................................................................14

(9) Adjusting the double chain looper (Applicable only to MO-6716D series) .........16

1) Returning amount of the double chain looper ....................................................................................16

2) Longitudinal motion (Avoid motion)....................................................................................................16

3) Clearance between the double chain looper and the needle .............................................................16

(10) Adjusting the height and clearance of the needle guard......................................18

1) For 1-needle or 2-needle overlock machine.......................................................................................18

2) For safely stitch machine ...................................................................................................................18

(11) Adjusting the height of the feed dog ......................................................................20

(12) Adjusting the tilt of the feed dog.............................................................................20

(13) Adjusting the differential feed ratio ........................................................................22

(14) Longitudinal position of the feed dog ....................................................................22

(15) Adjusting the presser foot.......................................................................................24

1) Adjusting the tilt of the presser foo....................................................................................................24

2) Adjusting the micro-lifting mechanism of the presser foot.................................................................24

(16) Positioning the upper knife arm shaft ....................................................................26

(17) Positioning the upper and lower knives, and available overedge widths...........26

1) Lower knife.........................................................................................................................................26

2) Upper knife.........................................................................................................................................26

3) Overdging width .................................................................................................................................26

(18) Resharpening of the knife........................................................................................28

(19) Position of the thread cam (Applicable only to MO-6716D series) ......................28

1) Adjustment of the thread cam ............................................................................................................28

2) Adjusting looper thread cam thread guides A and B and the looper thread cam nail.........................28

3) Adjusting looper thread auxiliary thread take-up lever (Exclusive for 30P)........................................30

(20) Adjusting the throat plate support..........................................................................32

(21) Adjusting the feed mechanism cover presser.......................................................32

(22) Adjusting the looper cover ......................................................................................34

(23) Adjusting the cloth chip cover ................................................................................34

(24) Position of the thread guides and the looper thread take-ups.............................36

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(25) Adjusting soft chain making mechanism...............................................................38

1) Replacing the parts with those exclusively designed for making soft chains .....................................38

2) Adjustment value................................................................................................................................38

3) Important points in adjustment ...........................................................................................................39

4. ADDITIONAL INFORMATION AND PRECAUTIONS.................................. 40

(1) Thread tension............................................................................................................40

1) Strength of tension spring ..................................................................................................................40

2) Springs used for each model .............................................................................................................40

(2) Upper looper .............................................................................................................40

(3) Center-to-center distance of the upper looper holder ..........................................41

(4) Caution in assembly.................................................................................................41

1) Application of sealant .........................................................................................................................41

2) Precautions to be taken with respect to the lubricating components .................................................43

3) Applying the exclusive grease............................................................................................................44

(5) Kinds of motor pulleys, belts and frame support plate bolts...............................46

1) Motor pulleys and belts ......................................................................................................................46

2) Pat No. of frame support plate bolt ....................................................................................................46

5. ADJUSTMENT VALUES OF THE NEEDLE HEIGHT

AND LOOPER TIMING ................................................................................ 47

(1) MO-6700D SERIES ....................................................................................................47

6. TROUBLES AND CORRECTIVE MEASURES ........................................... 48

7. DIMENSIONS OF TABLE ............................................................................ 60

(1) Semi-sunken type .....................................................................................................60

(2) Semi-sunken type (synchronizer is used)..............................................................61

(3) Fully-sunken type .....................................................................................................62

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1. SPECIFICATIONS

(1) MO-6700D SERIES

No. Item Specifications

1 Model MO-6704D MO-6714D MO-6716D 2 Description 1-needle Overlock 2-needle Overlock 2-needle Safety stitch

machine machine machine

3 Stitch type F. S. T. JIS E13 JIS E24 JIS E13+D12

(USA standard : 504) (USA standard : 514) (USA standard : 516)

4 Sewing speed 6000rpm 5 Stitch length 0.8 to 4mm 1.5 to 4mm 6Needle gauge 2.0, 3.2mm 3.2, 4.8mm

7Overedging width 1.6, 3.2, 4, 4.8mm 2.0, 3.2, 4mm 3.2, 4, 4.8, 6.4mm 8 Differential feed ratio Gathering 1 : 2 (Max.1 : 4), Stretching 1 : 0.7 (Max.1 : 0.6) 9 Needle bar stroke 24.5 mm (30P for light to medium-weight materials),

25.5 mm (40H for medium to heavy-weight materials) 10 Needle tilt angle 20° 11

Needle bar mechanism

Upper and lower needle bar bushing type 12 Needle ORGAN DC X 27 (Standard) (DC X 1 can be used as well.) 13 Presser lifting amount 7.0mm 6.5mm 7.0mm 14 Presser foot pressure 49N (5kg) 15

Stitch adjusting method

By pushbutton 16 Upper knife Flat knife 17

Differential feed adjustment

By lever with micro adjustment mechanism 18 Weight 28kg 19 Lubrication Automatic geared lubrication system and grease charge 20 Lubricating oil JUKI MACHINE OIL 18 (Equivalent to ISO VG 18) Product No.: MML018900CA 21 Grease Exclusive grease (Part No. 23640204) 22 Needle cooler Optional 23 Needle thread cooler Optional 24

Micro presser lifting device

Provided as standard

25 Motor 2P 400W

*1. Grease should be supplied to the needle bar system and upper looper system.

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2. MODEL NUMBERING SYSTEM

MO-6700D SERIES MODEL NUMBERING SYSTEM

1 2345678910111213 14 15 16 17 18 19 20 21 22 23 24 25 26

MO67 D /

3 to 6 Model classification

6704 1-needle 3-thread overlock 6705 Blind-hemming 6712 2-needle, 4-thread imitation safety stitch 6714 2-needle 4-thread overlock 6716 2-needle 5-thread safety stitch 6743 3-needle 6-thread safety stitch 6745 2-needle double chain stitch

7Type classification

D Semi-dry head

8 Needle gauge classification 0 1-needle

B 2.0mm D 3.2mm F 4.8mm

1 4.8+2.0mm

2 3.2+2.0mm

9 Overedging width classification A 1.6mm

B 2.0mm D 3.2mm E 4.0mm F 4.8mm H 6.4mm

10 Feed dog classification

42-row 51-row 63-row

11 Material classification

(classification applied to handling material and cloth) 1 Extra light- to right-weight material Light weight material such as dress shirt 2 3Light- to medium-weight materials General fabrics 4 Meduim- to heavy-weight materials Exclusive for knit such as sweater 5Medium weight material such as denim to heavy weight material

12 Application classification

(classification of application based on work and process) 0 Standard 1 For blind hemming 2 For ruffling 4 For tape attaching 5 For rolled hemming 6 For tape feeding

* *

The asterisk (*) indicates 3-needle type.

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13 Special machine classification

(special classification of machine,

structure and specs. other than gauge set) 0 Standard 7 Upper looper high throw

F Swim suits H Upper looper extra high lift P Puckering prevention

15 to 22 Device and attachment classfication G39/Q141 Presser for tape attaching (for sharp curve)/tape guide L121 Blind stitch hemming attachment S159 Swing-type gathering device (interlocked with pedal, for safety stitch machine) S162 Swing-type gathering device (manual lever operated, for overlock machine) N077 Clean finish top and bottom E35 Overedging lug replace type throat plate

24 Place of destination

A Standard

DU.S.A and Japan

G China (in China)

25 Accessories type

A Standard B Eouropa and U.S.A G China (in China)

26 Table type

0 Fully sunken type 1 Semi sunken type

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Model

DimensionADimensionBDimension

MO-6704D-0A -150 10.5 — — MO-6705D-0 -210 10.5 — — MO-6704D-0 -300 10.5 — — MO-6704D-0 -307 10.5 — — MO-6704D-0 -40H 11.3 — — MO-6704D-0F6-50H 11.3 — — MO-6714D-B - 7 10.5 9.1 — MO-6714D-B - H 11.3 9.9 — MO-6712D-DF6-50 11.0 9.4 — MO-6714D-B -30P 10.5 9.1 — MO-6716D- -300 10.5 — 9.8 MO-6716D-FF6-307 10.5 — 9.8 MO-6716D- - 11.3 — 10.6

MO-6716D- -30P 10.5 — 9.8

6704D 6705D

6712D 6714D

6716D

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

3. STANDARD ADJUSTMENT

(1) Adjusting the needle height

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.

(2) Positioning the throat plate

(Unit : mm)

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

(Unit : mm)

Overlock side A 1.3 Double-chainstitch side B 1.0

For 30P

(Safety stitch machine)

4 H 50H

Standard Adjustment

1-needle overlock

machine

2-needle overlock

machine

Safety stitch

machine

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Needle driving shaft

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

the needle height.

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

forked crank . 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.

o 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.

o Improper lateral position of the

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

o Improperly positioned throat plate

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

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

Adjustment Procedure Results of Improper Adjustment

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(3) Installing position of the needle clamp

Needle clamp connecting stud should fit with the bottom end of needle bar or be spaced within 0 to 0.5 mm.

(4) Adjusting the length of the lower looper holder (Applicable only to MO-6716D 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 3.5mm.

26mm

3.5mm

Butt the needle clamp with the bottom end of the needle bar.

0 to 0.5mm

Standard Adjustment

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1) Loosen setscrew and adjust, by slightly turning needle clamp , 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).

o 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.

o 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.

1) Loosen setscrew 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.

o Increasing the center-to-center

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

Adjustment Procedure Results of Improper Adjustment

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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.

(5) Adjusting the lower looper

Model MO-6704D-0A -150 4.0 MO-6705D-0 -210 4.0 MO-6704D-0 -300 3.8 MO-6704D-0 -307 3.8 MO-6704D-0 -40H 3.8 MO-6704D-0F6-50H 3.8 MO-6714D-B - 7 3.8 MO-6714D-B - H 4.0 MO-6712D-DF6-50 2.2 MO-6714D-B -30P 3.8 MO-6716D- -300 3.8 MO-6716D-FF6-307 3.8 MO-6716D- - 3.8

MO-6716D- -30P 3.8

(Unit : mm)

0.01 to 0.1 mm

Dimension

(66.9±0.2mm)

Standard Adjustment

1-needle overlock

machine

2-needle overlock

machine

Safety stitch

machine

2) Clearance between the lower looper and the needle

The clearance should be 0.01 to 0.1 mm.

4 H 50H

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o Excessive return of the lower

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

o Insufficient return of the lower

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

o Excessive clearance will often

cause needle thread stitch skipping.

o 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

Loosen setscrew of lower looper support arm and adjust lower looper to make adjustment of the returning amount.

(Referential information)

1. Radius K of lower looper will be 66.9 mm when the lower

looper is inserted into lower looper support arm until it contacts with stopper pin and then is fixed.

2. The rocking angle of the lower looper will be 26°.

2) Clearance between the lower looper and the needle

Loosen setscrew of lower looper support arm to the extent that it is temporarily tightened. Then finely adjust the longitudinal position of the looper using fine adjustment screw .

Turn fine adjustment screw clockwise to move lower looper away from the needle. Turn the screw counterclockwise to move lower looper closer to it.

Adjustment Procedure Results of Improper Adjustment

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MO- 6704D - 0E to 0F - 4 H

MO- 6714D - BB6 to BE6- 30P

BD4 to BE4 BD6 to BE6

MO- 6716D - - 30P

D F

(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 .

13131909 13132006

Model

Dimension

MO- 6714D - - 4 H

(Unit : mm)

Model

Dimension

(Unit : mm)

7 5.5

6.3 4.7

5.8

6.3

5.8

Marker dot

Frame guide surface

MO- 6716D - - 4 H

Standard Adjustment

Upper looper guide

support gauge

1-needle overlock

machine

2-needle overlock

machine

Safety stitch

machine

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1) Fit upper looper guide support gauge over gauge fixing pin which has been driven in frame 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 installing upper looper guide support , 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 sealantsî for the various

sealants.

o 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.

o If the upper looper guide has

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

Adjustment Procedure Results of Improper Adjustment

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(7) Positioning the upper looper holder

Model

MO- 6704D - 0E to 0F - 4 H 48.2

MO- 6714D - BB6 to BE6 - 30P 47.3

BD4to BE4 BD6 to BE6

MO- 6716D - - 30P 46.2

D F

MO- 6714D - - 4 H 48.4

Dimension

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

(Unit : mm)

Bottom surface of frame

53mm

0.2mm

MO- 6716D - - 4 H 48.2

Standard Adjustment

1-needle overlock

machine

2-needle overlock

machine

Safety stitch

machine

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

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

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

setscrew of upper looper ball arm .

(Caution) Replace upper looper holder according to the needle

gauge size.

o Inaccurately positioned upper

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

(Caution) To adjust the upper

looper ball arm, take dimension

as stan-

dard. 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.

Adjustment Procedure Results of Improper Adjustment

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(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

The clearance between upper looper

and lower looper should be 0.05 to 0.2 mm when they cross

with each other.

The clearance between upper looper and needle should be 0.01 to 0.2 mm.

0.05 to 0.2 mm

0.01 to 0.2 mm

Model

DimensionDDimension

MO-6704D-0A -150 11.0 4.0 MO-6705D-0 -210 11.0 4.0 MO-6704D-0 -300 11.0 4.0 MO-6704D-0 -307 10.3 4.4 MO-6704D-0 -40H 11.3 4.4 MO-6704D-0F6-50H 11.3 4.4 MO-6714D-B - 7 10.3 4.4 MO-6714D-B - H 10.5 4.8 MO-6712D-DF6-50 11.0 3.6 MO-6714D-B -30P 10.3 4.4 MO-6716D- -300 11.0 4.0 MO-6716D-FF6-307 10.3 4.4 MO-6716D- - 11.3 4.4

MO-6716D- -30P 11.0 4.0

(Unit : mm)

Standard Adjustment

Throat plate

1-needle overlock

machine

2-needle overlock

machine

Safety stitch

machine

4 H 50H

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1) Height of the upper looper

Set a hexagon wrench key onto setscrew at the end of upper looper bracket to adjust height D.

When adjusting the height, pay attention also to the clearance produced between the upper looper and lower looper at the time of their crossing.

2) Longitudinal position of the upper looper

Loosen setscrew at the top end of upper looper bracket to move upper looper back or forth for positioning the clearance of 0.05 to

0.2 mm between upper looper and lower looper at the time of their crossing or the clearance of 0.01 to 0.2 mm between upper looper

and needle .

o 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.

o 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.

o Excessive clearance will cause

stitch skipping.

o Insufficient clearance will cause

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

Adjustment Procedure Results of Improper Adjustment

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1.5 to 1.7 mm

(63.4 mm)

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 1.7 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.

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.

(9) Adjusting the double chain looper (Applicable only to MO-6716D series)

3.0 to 3.6 mm

0.05 to 0.1 mm

Standard Adjustment

Marker

Hole

Marker

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1) Returning amount of the double chain looper

Loosen setscrew of double chain lopper driving arm to make

this adjustment.

Radius Mof the double chain looper driving arm will be 63.4 mm when it is lowered until it comes in contact with stopper pin .

2) Longitudinal motion (Avoid motion)

Open the cover of the adjusting hole on the rear of the frame, loosen setscrew , 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)

Marker : Far side

..... Maximum (for thick needles)

3) Clearance between the double chain looper and the needle

Temporarily tighten setscrew 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.

o Excessive return of the double

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

o Insufficient return of the double

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

o If the avoid motion is too large,

triangle stitch skipping will often occur.

o Insufficient avoid motion will

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

o Excessive clearance will cause

frequent needle thread stitch skipping.

o 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.

As observed from this side

Adjustment Procedure Results of Improper Adjustment

Bad needle entry

Good needle entry

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

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

The overlock machine has two needle guards, A and B. The needle guard B should be located 1 mm below 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

Throat plate

1 mm

0.1 mm

Throat plate

5 mm

0.1 m m

(Traveling needle guard)

Standard Adjustment

Light touch the needle guard

Lightly touches

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

Adjust needle guard A with setscrews in the needle guard so that it lightly comes in contact with the needle when the blade point of the lower looper reaches the needle center.

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 in the needle guard support and turn needle guard B to adjust the clearance to 0.1 mm.

Adjust the height of needle guard B to 1 mm from the throat plate bottom surface with setscrew in the needle guard.

2) For safety stitch machine

Loosen setscrews 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.

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

in the needle guard.

Adjust the clearance provided between needle guard D and the needle to 0.1 mm with setscrews .

(Caution) Check again the clearance provided between needle guard

and the needle after adjusting the height of needle

guard C.

o Excessively close contact

between the needle guard

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

oA 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.

o 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.

o 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.

oExcessive clearance between

the needle guard Band 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.

o If the needle guard C is too high,

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

o 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 bend of needle, wear on the needle guard and scratches on the needles will occur.

o Excessive clearance left be-

tween 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.

Adjustment Procedure Results of Improper Adjustment

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(11) Adjusting the height of the feed dog

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

[Standard] Auxiliary feed dog is 0.5 mm lower than main feed dog . B = 0.5 mm [30P] Auxiliary feed dog is as high as main feed dog . B = 0 mm

Model Dimension A

MO-6700D series (30P excluded) 1.0 MO-67 D- -30P 0.8

(12) Adjusting the tilt of the feed dog

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

Model Dimension A Dimension B MO-6700D series (30P excluded) 1.0 (1.2) MO-67 D- -30P 0.8 (0.9)

(Unit : mm)

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

Top surface of the throat plate

Feed dog is leveled.

Needle

entry

Front up

(Unit : mm)

In case of 30P type

Standard Adjustment

Needle

entry

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o 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.

o If the feed dogs are too low, in-

sufficient feed power will result.

o If the auxiliary feed dog is too

high, chain-off thread will be often jammed.

o If the main feed dog and differ-

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

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

2) Adjust the height of differential feed dog with setscrew so that

there is no difference in level between main feed dog and differential feed dog .

3) Adjust the height of auxiliary feed dog with setscrew so that it is

0.5 mm lower than main feed dog .

o When tilted with the front up

Good material catching will be obtained.

oWhen tilted with the front down

Uneven feed and puckering will be effectively prevented.

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 consists of an eccentric shaft. Loosen setscrew 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 direc-

tion).

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.

Adjustment Procedure Results of Improper Adjustment

Page 26

– 22 –

(13) Adjusting the differential feed ratio

(Standard)

Gathering: 1: 2

Stretching: 1: 0.7

(Max, stretching)

Gathering: 1:1.6 Stretching: 1:0.6

(Max, gathering)

Gathering: 1: 4

Stretching: 1: 1.3

Pin at its highest position

Washer

Pin at its lowest position

(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

Standard Adjustment

Center of nut Lower marker line

Page 27

– 23 –

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

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

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

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

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

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

o 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

1) Remove the cover on the rear of the frame, loosen main feed bracket clamping screw and differential feed bracket clamping screw , 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 and differential feed bracket clamping screw .

Adjustment Procedure Results of Improper Adjustment

Page 28

– 24 –

(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

Standard Adjustment

Page 29

– 25 –

o Uneven contact will result in bad

straight material feed and weak feed force. Puckering is apt to occur as well.

1) Adjusting the tilt of the presser foot

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.

Loosen setscrew and adjust so that the presser foot sole comes in contact evenly with the throat plate top surface. Then tighten setscrew .

(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

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

adjustment screw .

Adjustment Procedure Results of Improper Adjustment

Page 30

– 26 –

1) Lower knife

2) Upper knife

3) Overedging width

Overedging width can be adjusted from 1.6 to 6.4 mm.

(16) Positioning the upper knife arm shaft

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

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

34mm

Lower knife

Throat plate

Standard Adjustment

Upper knife

0.5 to 1 mm

Page 31

– 27 –

oImproperly 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.

1) Remove the upper cover, loosen setscrew in upper knife driving arm , and turn upper knife shaft 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 is subjected to high load.

o The lower knife, if positioned too

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

o If the lower knife is positioned too

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

o The upper knife, if positioned too

high, will fail to cut materials.

o Failure of 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.

1) Lower knife

Adjust the vertical position of the lower knife by screw so that the blade top aligns with the top surface of the throat plate.

Tighten screw after bringing the upper knife to its lowest position of its stroke.

2) Upper knife

Adjust the position of the upper knife by screw 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 .

Adjust the lateral position of the upper knife by screw . After performing adjustment, be sure to fix the knife. Otherwise, the durability of the knife will be affected.

3) Overedging width

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

Adjustment Procedure Results of Improper Adjustment

Page 32

– 28 –

(18) Resharpening of the knife

(19) Position of the thread cam (Applicable only to MO-6716D series)

1) Adjustment of the thread cam

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

10°

55°

Standard Adjustment

Level

Page 33

– 29 –

1) Adjusting the thread cam

Adjust the position of the thread cam by its setscrew with the needles at their upper dead point so that the straight section of the thread cam is leveled.

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

Install looper thread cam thread guides A and B at the center of the slots with setscrews A and B .

Install looper thread cam nail with setscrew so that the straight section of the forked portion is leveled.

o If the 10∞ angle of the lower knife

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

o If the angle is smaller than 10°,

the knife will be dull.

o If the 55° angle is not observed,

the knife may catch materials.

1) When the knives have become dull, fully resharpen lower knife 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.)

o 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.

o If the timing of the thread cam is

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

o 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.

Throat plate

0 to 1 mm

Thread

Adjustment Procedure Results of Improper Adjustment

Page 34

– 30 –

(19) Position of the thread cam (Applicable only to MO-6716D series)

3) Adjusting looper thread auxiliary thread take-up lever (Exclusive for 30P)

When lopper thread auxiliary thread take-up lever is in its lower dead point, the thred hole should align

with the hole in lopper thread auxiliary thread take-up lever guide .

The holes should align with each other at the lower dead point.

Standard Adjustment

Page 35

– 31 –

1) Open the cloth base cover and loosen setscrew .

2) When looper thread auxiliary thread take-up lever is in its lower dead point (when the feed dog goes back to the end), tighten setscrew so that the thread hole in looper thread auxiliary thread take-up lever aligns with the thread hole in looper thread auxiliary thread take-up lever guide .

(Caution) 1. When the feed pitch is changed, perform re-adjustment.

2. Confirm that looper thread auxiliary thread take-up le-

ver does not come in contact with the cloth base cover.

Adjustment Procedure Results of Improper Adjustment

Page 36

– 32 –

(20) Adjusting the throat plate support

(21) Adjusting the feed mechanism cover presser

Standard Adjustment

Uniform contact

Page 37

– 33 –

oIf 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.

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

o If the feed mechanism cover is

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

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

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

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

should not rise.

Adjustment Procedure Results of Improper Adjustment

Page 38

– 34 –

(22) Adjusting the looper cover

o The looper cover should smoothly close without coming in contact with upper knife when slowly closing

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

(23) Adjusting the cloth chip cover

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

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

(There are 2 pcs. inside.)

Frame

Cloth chip cover

Standard Adjustment

Page 39

– 35 –

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

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

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

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

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

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

Adjustment Procedure Results of Improper Adjustment

Page 40

– 36 –

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

Needle thread guide

Needle thread take-up guide of double-chainstitch machine

Needle thread takeup lever of doublechainstitch machine

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

MO-6704D MO-6714D MO-6716D

Needle thread take-up

Needle thread guide

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.

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.

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.

Upper looper thread guide (upper)

Upper looper thread guide (middle)

Looper thread take-up (left)

Looper thread t

ake-up (right)

Lower looper thread take-up

Upper looper thread guide (right)

Lower looper thread guide

MO-6 04D MO-6 14D MO-6 16D MO-6 16D MO-6 05D MO-6 04D

(Standard) (Standard) (Standard) (50H) (Blind-hemming) (Soft chain)

General thread Wooly thread General thread Wooly thread General thread Wooly thread General thread General thread Wooly thread General thread

15.8 ←←←←← ← ← ← 13.5

3.4 ←←←1.8 ← 2.6 3.4 ← 2.1 ————21.5 ← 2.3 — — — ————30.5 ← 24.5 — — —

22 ←←←←← ← ← ← ← 65 ←←←←← ← ← ← ←

17.5 ←←←←← ← ← ← ←

43.5 ←←←←← ← 40.5 ← 43.5

26.5 ←←←←← ← 24 ← 26.5 38 41 38 ← 34 36 34 38 42 43.5 15 ← 12 15 12 15 12 12 ← 14

6.5 ← 10 ← 6.5 ←← 24 34 ← 29 ←←←27.5 ←← 29 ← 26.5 27 21 23 ← 20 ← 19 24 ← 19

11 ←←←←← ← 12 ← 9.5 ————16← 12.8 — — —

Symbol

B C D

F G H

I J K L

M N O

(Unit : mm)

Standard Adjustment

Page 41

– 37 –

1) Perform the adjustment by the setscrews. Position of the needle thread guide and needle thread take up 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.

o Distance

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

o Distance E, F and H exert least

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

o 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.

oDistance 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.

o 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.

o 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.

o 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.

o 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.

Swell out

Adjustment Procedure Results of Improper Adjustment

Needle thread take-up amount

Large

Small

Lower looper

Thread slack

Upper looper

Needle

Thread slack

Page 42

– 38 –

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

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

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

Needle thread presser spring B ..... 12112702

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

overlock machine)

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

2) Adjustment value

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.

(04 1-needle overlock machine) (16 Safely stitch machine)

Adjust the rising amount of needle thread presser plate C.

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

Rising amount : 0.6 to 1 mm (max.)

(25) Adjusting soft chain making mechanism

Max. slot of the needle thread guide

3.1 to 3.6mm

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

Standard Adjustment

Cam face

Needle thread take-up amount when the needle bar is in its lowest dead point

Rising amount

Cam face

Page 43

– 39 –

3) Important points in adjustment

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.

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.

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.

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.

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.

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.

Soft chain stitches

Standard stitches

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

Looper thread take-up (left)

Looper thread take-up (right)

Lower looper thread take-up

Lower looper thread guide

Upper looper thread guide (middle)

Upper looper thread guide (upper)

Upper looper thread guide (right)

29 (27.5)

27 (20)

17.5

15 (12)

E 22

26.5

43.5 J

(34)

6.5

Looper thread should not be loosened and stretch well

The looper thread loosens

When the chain-off thread is pulled.

Page 44

– 40 –

(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.

Model Nos. engraved on Needle No.

upper looper (kind)

MO-6704D series *1188 81 #9 #11 #14 MO-6716D series

MO-6714D series *1217 60

Part No. Color Natural length Operating length Weight required to compress

(mm) (mm) spring to working length

13137807 Red 19.5mm 11.5mm 4.21±0.49N (430±50g)

13138508 Yellow 17.8mm 9.8mm 3.14±0.34N(320±35g)

13138805 Blue 17.3mm 9.3mm 1.47±0.20N(150±20g)

4. ADDITIONAL INFORMATION AND PRECAUTIONS

2) Springs used for each model.

Needle thread Double-chainstitch Upper looper Lower looper

needle thread thread thread

MO-6704D series Red — Yellow Blue MO-6714D series Red • Yellow — Blue Yellow MO-6716D series (30P included) Red Yellow Yellow Blue MO-6716D- -4 H, -50H Red Red Blue Yellow

Model

Where to use

(1) Thread tension

1) Strength of tension spring

Page 45

– 41 –

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

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

Be careful not to allow the sealant to run to the rear.

Apply the sealant to the bottom surface.

(4) Caution in assembly

1) Application of sealant

Setscrew of the throat plate base (B) retainer (JUKI seal) Apply the sealant only to the right setscrew.

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

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

After assembling the front edge of the upper looper guide support (JUKI seal), apply the sealant to the gap of the contact surface between the frame and the upper looper guide support ( section in the illustration).

Frame

Apply only to the right setscrew

Model

MO-6704D - MO-6705D - - 0

MO-6704D - 0E4 40H

0F6 50H MO-6712D -D MO-6714D - MO-6716D - - 0

MO-6716D -DE to FF MO-6743D - - 40H

(Unit : mm)

39 39

38 39

4 H 5 H

Center-to-center

distance

Page 46

– 42 –

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)

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

Various sealants

Maker’s name Part No.

Three Bond 1104D Three Bond 1104 Three Bond 1212

* * : It is commonly called “JUKI seal”.

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

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

Oil shield plate assembly (JUKI seal) Apply the sealant to the inside of the oil shield plate .

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.

Inside contact surface

Apply the sealant to the top surface of the oil shield plate.

Page 47

– 43 –

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

Feed bar components

o Be careful of the orientation of the oil shield rubber and the dust-proof rubber .

* Assembling as shown in the illustration

will result in oil leakage. So, be careful.

Portion converted to dry-head type

Forced lubrication room

[Wet portion]

3. Upper looper mechanism portion [Dry portion]

1. Needle bar mechanism portion [Dry portion]

2. Feed mechanism portion [Wet portion]

o Assemble the feed bar presser and the dust-

proof rubber case so that their top faces are flush with the frame plane on which the feed mechanism cover is installed.

o Do not loosen the screws in feed bar presser

unless it is necessary. The clearance between the feed bar presser and the feed bar and the contact with each other are important.

Do not loosen the screws.

Page 48

– 44 –

3) Applying the exclusive grease

o The exclusive grease (23640204) is applied to the necessary components other than the lubricating com-

ponents. Never use any grease other than the exclusive one.

It is not necessary to additionally apply grease to the components when the sewing machine is used under the normal condition. When the machine is used under the specially severe condition, it is effective to periodically (once a year or every other year) fill up the exclusive grease.

* : Apply the exclusive grease.

Needle bar components

(Caution) There are grease grooves on the inside

of needle bar upper metal (No. 19) and needle bar lower metal (No. 18). Fill up the exclusive grease to the groove portion when drawing out the needle bar.

Page 49

– 45 –

Upper looper components

Page 50

– 46 –

2) Pat No. of frame support plate bolt

Semi-sunken type Support plate bolt (A) 13155007 x 4

Locknut NS6240630SE x 4 Washer WP1002036SE x 4 Spring washer WS1002560KR x 4

Fully-sunken type Support plate bolt (C) 13155106 x 2 Support plate bolt (D) 13155205 x 2 Locknut NS6240630SE x 12 Washer WP1002036SE x 12 Spring washer WS1002560KR x 4

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

(mm) (mm) Support plate bolt (A) 69 39 Support plate bolt (C) 137 107

Support plate bolt (D) 149 119

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

1) Motor pulleys and belts

50Hz 60Hz

V-belt V-belt

Semi-sunken type Fully-sunken type Semi-sunken type Fully-sunken type

mm (inch) mm (inch) mm (inch) mm (inch)

6000 110 (105) 914 (36) 813 (32) 95 (90) 889 (35) 762 (30) 5500 100 (95) 914 (36) 813 (32) 85 (80) 889 (35) 762 (30) 5000 90 (85) 889 (35) 762 (30) 80 (75) 864 (34) 762 (30) 4500 85 (80) 889 (35) 762 (30) 70 (65) 864 (34) 762 (30) 4000 75 (70) 864 (34) 762 (30) 60 (55) 864 (34) 737 (29)

Sewing

speed of

sewing

machine

(rpm)

* A motor with 1/2 horsepower (400 W) or more shall be used.

(Caution) If a motor of less than 400W is used, in the low temperature 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 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 889 mm (35 inches), enter “35” to “xx.”

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

Outside diameter

of motor pulley mm

(effective diameter

mm)

Outside diameter

of motor pulley mm

(effective diameter

mm)

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

69mm

39mm

137mm

107mm

149mm

119mm

Page 51

0A5 to 0F5 15

MO- - 0A4 to 0E4 - 210

0D6 3

MO-6704D - 0F4 -30

0D4 to 0E4

MO- 6704D- 0F6 - 4 H

50H

MO- 6714D- BD6 to BE6- 7

MO-6714D - B 6 - 30P

MO- 6714D- BD to BE - H

MO- 6712D- DF6 -50F

MO- 6716D- -30

MO- 6716D-

to F

-4

50H

MO- 6743D- 2D6 - 40H

MO- 6745D- FF4 - 360

13131008 13131107

13131909 13132006

Needle height Upper looper components

Lower looper components

Double-chain looper

1-needle 2-needle Upper looper Projection of Upper looper Marker of Position of

Guide support

Center-to- Marker of Feed amount Radius of Feed amount Radius of

2-needle (right) height upper looper

holder height

guide support guide support

cover

center of upper

upper looper of lower lower looer of double- double-chain

(left) of pin looper holder holder chain looper looper

10.5±0.1 — 11.0±0.3 4.0±0.3 (45.0) A 38 4.0 66.9 — —

10.5±0.1 — 11.0±0.3 4.0±0.3 (46.2) A 38 3.7 66.9 — —

11.3±0.1 — 11.3±0.3 4.4±0.3 (48.2) A 39 3.8 66.9 — —

10.5±0.1 (9.1) 10.3±0.3 4.4±0.3 (47.3) B 39 3.8 66.9 — —

10.5±0.1 (9.1) 10.3±0.5 4.4±0.3 (47.3) B 39 3.8 66.9 — —

11.3±0.1 (9.9) 11.0±0.5 4.8±0.3 (48.4) A 39 3.8 66.9 — —

11.0±0.3 (9.4) 11.0±0.5 (46.9) B 39 2.2±0.3 66.9 — —

10.5±0.1 — 11.0±0.3 4.0±0.3 (46.2) A 38 3.7 66.9 1.5 to 2.0 63.4

1.3±0.1 — 11.3±0.3 4.4±0.3 (48.2) A 39 3.8 66.9 1.5 to 2.0 63.4

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

9.8±0.1 — — — — — — — — — — — 2.0 to 2.5 63.6

5.8

– 47 –

Description

Subclass

6704D 6705D

5. ADJUSTMENT VALUES OF THE NEEDLE HEIGHT AND LOOPER TIMING

(1) MO-6700D SERIES

#81

(11888609)

40004713

Marker A

+0.5 –0.8

+0.5 –0.7

#81

(11888609)

6.3 40004713

+0.5 –0.8

#19

(11991908)

5.8

40004713

+0.5 –0.8

#60

(12176004)

40004714

+0.5 –0.8

#61

(12176103)

5.8

+0.5 –0.8

40004713

#60

(12176004)

40004714

#66

(11996600)

5.5 40004714

3.6±0.3

(Right side)

#81

(11888609)

6.3 40004713

+0.5 –0.7

+0.5 –0.8

#19

(11991908)

5.8 40004713

#61

(12176103)

40004713

1- needle overlock

macine/safety stitch machine

3- needle

safety stitch

2- needle overlock

macine

3- needle

safety stitch

2- needle overlock

macine

3- needle

safety stitch

7 5.5

5.8

6.3 4.7

+0.5 –0.8

(Unit : mm)

Needle height

Upper looper components

Lower looper components

Double-chain looper components

2- needle overlock

macine

1-needle overlock machine

2-needle overlock machine

Safety stitch machine

Classification

Upper looper

guide support

gauge

Upper looper

holder

1D6

Page 52

1. Needle thread breakage Threading The thread is entangled with the thread Refer to the threading diagram. guide, or the machine head has been (Refer to the Instruction Manual) incorrectly threaded.

Thread path Scratches, burrs or rust on the pawls Remove such scratches, burrs, etc. and

or needle holes of the throat plate,

perform thread path finishing. Replace major

stitch tongue, lower looper, double chain

components such as looper, which have looper, needle thread take-up, needle been deformed, causing thread breakage. thread presser spring, thread guide, or tension discs causes friction.

Needle guard The needle hits the needle guard intensely, Replace the needle and needle guard if 18

and sharp edges are produced on them, they have worn, causing thread breakage.

Needle The needle is too thin for the thread. Replace the needle by a proper one.

Needle heat The needle gets very hot, depending on Use a thinner needle. Reduce the sewing

the type of materials, number of plies and speed. Use the needle cooler. Use an S-point sewing speed, and causes the thread to needle or needle for synthetic thread. burn and break.

Thread

The thread is weak because of its poor quality.

Replace the thread by one with good quality.

Thread tension The thread tension is too high. 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.

Contact The double chain looper or lower looper Properly position the double chain looper or 8, 16

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

Double thread hooking Poor drawing up of the needle thread Increase the needle thread tension. Properly 28 (only for double chain stitch) causes the looper to catch it again. position the thread cam. Properly position the

double chainstitch thread guide.

Defective double chain-off thread Refer to the clause referring to defective (only for double chain stitch) double chain-off thread.

6. TROUBLES AND CORRECTIVE MEASURES

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

– 48 –

Page 53

2. Looper thread breakage Thread path Scratches, burrs, rust, etc, on the paw of Remove such scratches, burrs, etc. and carry the throat plate, stitch tongue, looper, out thread path finishing. Replace loopers or looper thread take-up, thread guide, other components which have been deformed, or tension discs causes friction. causing thread breakage.

Adjustment of the looper thread take-up The looper thread take-up or thread guide Refer to the pertinent Standard Adjustment. 36

has been improperly positioned, causing excessive thread tension.

Thread tension The looper thread tension is too high. Reduce the tension while checking the tension

balance other looper thread.

Thread The thread is weak because of its poor Replace the thread by one with good quality.

quality.

Position of the thread guides The upper looper thread guide is too high, Refer to the pertinent Standard Adjustment. 36 (only for double chain stitch) and the thread taking balance is disturbed,

resulting in the thread breakage.

Double chain looper avoid The double chain looper strikes the needle Correct the longitudinal motion of the double 16

at the back, causing the thread breakage. chain looper so as not to cause the looper to

strike the needle.

Needle heat The needle gets hot, and the looper thread Refer to the clause relating to the needle heat

breaks when it comes in contact with the causing needle thread breakage. hot needle at the time of needle stop.

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

3. Needle breakage Needle entry The needle entry has not been correctly Correct the needle entry. 4 adjusted, and the needle strikes the throat plate or presser foot.

Upper looper position The upper looper juts out too much or Refer to the related Standard Adjustment. 14

it is too low.

Contact with the looper The needle strikes the looper, resulting Re-position the looper so that it does not come

in needle breakage. in contact with the needle. Adjust the longitudinal

motion of the double chain looper for the contact of its back with the needle.

▼

– 49 –

to the next page

Page 54

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

From the previous page

Needle guards A needle guard has been improperly Refer to the pertinent Standard Adjustment. 18

positioned, causing the needle point to strike it.

Needle No. The needle is too thin for the materials. Replace the needle with a thicker one.

Thread tension The thread tension is too high. Reduce the thread tension.

Height of the feed dog or needle The feed dog is too high, or the needle is Refer to the related Standard Adjustment. 4, 20

too low, causing the needle to deflect with resultant needle breakage.

4. The needle point is crushed. Needle guard The needle guard C is too low, or its Increase the height of the needle guard (C). 18

(Double chain stitch needle) longitudinal position is not correct. Check the clearance between the needle and

needle guard.

Contact with the looper The tilt of the looper is not correct. The

Check the tilt of the looper. Correct the longitudinal

16 longitudinal motion of the looper is not motion of the looper, and increase the clearance correct. between the looper and needle when the

looper reaches its most retracted position.

▼

5. Overlocking needle thread stitches Lower looper The blade point has defective shape and Replace the lower looper. are skipped. does not catch needle thread loops.

Adjustment of the loopers. The clearance or the amount of return is Refer to the relevant Standard Adjustment. 8

not correct.

Needle thread presser The duration in which the presser holds the Refer to the pertinent Standard Adjustment.

needle thread is not correct, and unstable loop result.

Needle The needle is bent or improperly oriented. Replace the bent needle. Correctly orient and

A needle or DC x 1 is used. attach the needle.

Use a DC x J27 needle for a stretchy thread.

Needle guards Incorrect height or clearance prohibits Refer to the pertinent Standard Adjustment. 18

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

The lower looper fails to catch needle thread loops.

Right side Wrong side

– 50 –

to the next page

Page 55

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

Height of needle The needle has incorrect height and does Refer to the related Standard Adjustment. 4, 8

not properly pick up loops even if the looper has a correct return.

Needle heat Stitch skipping occurs before the thread Refer to the clause relating to the needle thread

breaks due to needle heat. breakage due to needle heat.

Positioning of the needle thread take-up They are positioned too high, and the Refer to the pertinent Standard Adjustment. 36 guide and needle thread guide needle thread take-up takes too much

thread, producing too small loops.

Threading The thread has been entangled with a See the threading diagram.

thread guide. (Refer to the Instruction Manual) The reading has bot been correctly done.

6. Lower looper stitches are skipped Threading The thread has been entangled with a Refer to the threading diagram. thread guide. (Refer to the Instruction Manual) Threading has not been done correctly.

Upper looper The blade point has a bad shape, and Replace the upper looper with badly

fails to catch the loops. deformed blade point.

Lower looper The clearance between the needle and Replace the lower looper having a deformed

the back of lower looper are not correct. tip.

Adjustment of the loopers The feed amount of the lower looper, height Refer to the relevant Standard Adjustment. 8, 14

of the upper looper, or clearance produced at time of crossing of the upper and lower oopers is not correct.

Thread amount Too much lower looper thread is fed, Slightly lower the looper thread take-up (left) 36

giving slack of thread. (reduction in distance J), or slightly reduce

distance I to decrease the amount of thread.

Slightly raise the looper thread take-up (right) 36 (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.

– 51 –

From the previous page

Right side Wrong side

Page 56

Viewed from the wrong side

Two stitches are skipped.

8. Double chain stitches are skipped. Needle height If the needle is not correct, stitch skipping Refer to the pertinent Standard Adjustment. occurs even when the return of the chain looper is correct.

Needle The needle is bent or attached with wrong Replace the bent needle. (Remove the cause

orientation. A DC x1 needle is used. for the needle bend.) Correct the orientation of

the needle. Use a DC x27 needle (with a better recess configuration).

Double chain looper The lower part of the blade point has been Replace the double chain looper.

deformed, and the blade point fells loops.

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

Upper looer thread stitches are skipped.

Threading The thread has been entangled with a See the threading diagram.

thread guide. (Refer to the Instruction Manual) Threading has not been done correctly.

Needle height The needle, if positioned too high or low, Refer to the related Standard Adjustment 4

may fail to catch the upper looper thread.

Needle The needle is bent or crushed, in its point. Replace the needle. At this time, be sure to

eliminate the cause for such needle bend or needle point crush.

Adjustment of the upper looper. The height of the blade point is not correct, Refer to the relevant Standard Adjustment. 4, 14

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.

Amount of thread Excessive upper looper thread is fed, Slightly lower the looper thread take-up (left) 36

producing stack of thread. (reduction in distance J), or slightly reduce

distance I to decrease the amount of thread. Make the upper looper thread guide (right) (shorter decrease in distance K), to reduce the amount of thread.

Slightly raise the looper thread take-up (right) 36 (increase in dimension O) to decrease the amount of thread.

If the thread tension is not enough, increase it.

The needle does not take the upper looper thread.

The double chain looper tails to catch needle thread loops.

▼

Right side Wrong side

Lower looper thread

Needle

Upper looper

– 52 –

Needle

Slack of thread

to the next page

Page 57

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

Adjustment of looper Clearance or returning amount is not correct. Refer to the related Standard Adjustment. 6

Thread tension The thread tension is too high, preventing Reduce the tension. However, be careful not

formation of good loops. to reduce the tension too much, otherwise

unstable loops will result.

Needle guards A needle guard is too high, and loops are Refer to the relevant Standard Adjustment. 18

crushed. The clearance is too big, causing the needle to shake.

Needle heat The thread breaks due to heat generated Use a thinner needle. Reduce the sewing speed.

on the needle, depending on the type of Check the coolant if necessary. materials, number of plies, and sewing speed.

9. Triangle double chain looper thread The needle point is crushed. The needle point has been crushed and Refer to the clause relating to the needle point

stitches are skipped. got thicker and shorter. crush.

Double chain looper The thread hole in the tip has worn, and Replace the double chain looper.

the looper thread does not reach the needle as shown at right.

Adjustment of looper Excessive return or longitudinal motion Refer to the pertinent Standard Adjustment. 16

will often cause this stitch skipping.

Thread cam timing The thread cam timing is too early, causing Refer to the pertinent Standard Adjustment. 28

the looper thread to slack before the needle enters a thread triangle.

Thread tension The lower thread tension is very low, and Increase the thread tension a little.

the thread is not stretched.

Threading he area around the thread cam has Correct the threading.

threaded erroneously.

The needle fails to catch the double chain looper thread.

Viewed from the wrong side

One stitch is skipped.

– 53 –

From the previous page

Needl

Page 58

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

10. Triangle double chain needle Double chain looper The chain looper is too high and too close Correct the height of the chain looper by 16 thread stitches are skipped. to the throat plate, or has bad shape. pushing it down until it cones into contact

with the stopper. Replace the chain looper having a bad shape.

Adjustment of looper The return is not enough, causing the Refer to the related Standard Adjustment. 16

needle to miss the loop.

Thread tension The needle thread tension is too low. Slightly increase the needle thread tension.

Stitch length The stitch length is as small as 1.5 mm Slightly increase the stitch length.

or less.

Adjustment of loopers for producing chain-off 28 thread without materials requires higher accuracy than that with materials.

Needle guard A needle guard is too high, and catches Refer to the related Standard Adjustment. 18

needle thread loops.

Double-chain stitch needle thread The needle thread guide is installed too Refer to the related Standard Adjustment. 36 guide. high, and it fails to tense the thread.

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

11. Overlocking chain-off thread is bad. Position of the throat plate The throat plate has been improperly Correctly position the throat plate. positioned longitudinally, and chain-off thread gets in between the main feed dog and throat plate, causing defective chain-off thread.

Feed dog The auxiliary feed dog has scratch. Repair or replace the auxiliary feed dog. 20

The auxiliary feed dog is too high, and Refer to the pertinent Standard Adjustment. 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 looper Adjustment of loopers for producing Refer to the related Standard Adjustment. 8

chain-off thread without materials requires higher accuracy.

Thread tension The thread tension is too low. Slightly increase the tension.

The needle thread tension is too high, Check whether the needle thread take-up 36 causing damaged balance with other guide or needle thread guide is positioned thread tension. too high with consequent excessive needle

hread tension. And if so, correct it.

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

Defectively interlaced loop Needle thread

The needle thread extends to the adjacent stitch.

– 54 –

Page 59

12. Problems with double chain stitch Adjustment of loopers Adjustment of the loopers for producing Refer to the related Standard Adjustment. 16 chain-off thread. chain-off thread without materials requires

higher accuracy.

Needle Guard The needle guard (C) is too high, Refer to the related Standard Adjustment. 18

damaging loops.

Position of the throat plate The needle comes into contact with the front Correctly position the throat plate.

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.

Throat plate A dent exists on the flat part between the Repair or replace the throat plate, since such

rear edge of the needle hole and feed dog dent causes chain-off thread to slip out. groove.

Presser foot The rear pressure foot is indented and not Replace it, or correct it to make it flush with

flush with the presser foot sole, so that it the presser foot sole. cannot hold chain-off thread.

Main feed dog The leading edge of the main feed dog is Buff the leading edge of the main feed dog.

too sharp and cuts chain-off thread.

Double hooking The needle thread is not drawn up fully Refer to the related Standard Adjustment for 16, 28

because of the insufficient return of the the return of the double chain looper. See the double chain looper or wrong threading. threading diagram for correct threading.

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

Thread tension The needle is bend or chain-odd thread Reduce the needle thread tension.

runs back due to excessive needle thread tension.

Both the needle thread and looper thread Slightly increase the both tensions. tension are too low.

Dent

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

– 55 –

Page 60

14. Double chain stitch needle thread Thread tension The looper thread tension is too high, and Reduce the looper thread tension to a minimum, is loose. the needle thread tension is too low. and increase the needle thread tension.

Thread cam The thread cam draws out an insufficient Refer to the relevant Standard Adjustment. 28

amount of thread.

The thread cam timing is bad. Refer to the relevant Standard Adjustment. 28

Needle The needle is too thin for the thread used. Replace the needle with a proper one.

Double-chain stitch needle thread Drawing amount of the needle thread is Refer to the relevant Standard Adjustment. 36 take-up guide insufficient.

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

13. Overlocking needle thread is loose. Position of the needle thread take-up They are positioned too high, and the thread Refer to the pertinent Standard Adjustment. 36 guide and needle thread guide take-up draws out excessive needle thread.

Thread tension The thread tension balance has been Refer to the Standard Adjustment for the looper

disturbed. thread take-up components, and increase the

tension if necessary.

Needle The needle is too thin for the thread used. Replace it with a proper one.

15. Uneven overlocking stitches Looper thread tension The upper and lower looper thread tensions Slightly increase the upper and lower looper

are not enough. thread tensions.

Looper thread take-up The looper thread take-up (left) is too high. Slightly lower the looper thread take-up (left) 36

Knife width The knife width is unsuited for the Make the overedging width slightly smaller than 26

overedging width. that given for the knife width.

Thread path Scratches on the thread path catch thread. Check the thread path for scratches.

Presser foot The presser foot cones into contact unevenly Make the presser foot come into contact with

with the throat plate and feed dogs and tends them evenly. to meander.

Thread stand Thread dose not come out smoothly. Make the thread come out smoothly.

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

– 56 –

Page 61

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

16. Uneven double chain stitches Thread tension The looper thread tension is not enough. Slightly increase the tension.

Presser foot The presser foot comes into contact with Make the presser foot come into contact with

the throat plate unevenly. the throat plate evenly.

The presser foot pressure is not enough. Increase the presser foot pressure.

17. The looper thread bulges out Knife width The knife width is too small for the Use a knife having width suited to the

overedging width. overedging width.

Looper thread take-up adjustment The looper thread take-up draws out Decrease the radius of the looper thread take-up 36

excessive looper thread. (left) (reduction in dimension I). Raise the looper

thread take-up (right) (increase in distance O).

18. Looper thread bite Knife width The knife width is too large for the Use a knife having width suited to the

overedging width. overedging width.

Adjustment of the looper thread take-up The looper thread take-up draws out Increase the radius of the looper thread take-up 36

insufficient amount of looper thread. (left) (increase dimension I). Lower the looper

thread take-up (right) (reduction in distance O).

19. Knotting position is not correct. Threading Re-threading after thread breakage,etc. See the threading diagram.

has been done erroneously. (Refer to the Instruction Manual)

Adjustment of the looper thread take-up The height of the looper thread take-up Raise the looper thread take-up (left) to increase 36

(left) is not correct. the amount of upper looper thread, and the

knotting position moves toward the lower looper side.

The upper looper thread guide (right) is Increase distance K. too short.

Knots are deflected to the upper looper side.

Right side

– 57 –

Page 62

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

20. Uneven material feed Presser foot pressure The presser foot pressure is too high. Reduce the presser foot pressure except for

the uneven material feed due to puckering.

Presser foot The hinge is too stiff. Remove the stiffness provided no hinge play

is produced.

Scratches on or defective finish on the Buff the presser foot sole for good surface presserfoot sole produce friction between finish. the presser foot and materials.

Tilt of feed dogs The front is too high. Make the front down. However, be sure to align

the differential feed dog with the main feed dog.

Height of feed dogs A different in level exists between the main Eliminate the difference in level.

feed dog and differential feed dog.

Adjustment of differential feed The differential feed has been improperly Provide differential feed suited to the material.

adjusted.

21. Puckering Needle The needle is too thick. Use a thin needle as much as possible.

Thread The thread used is too thick. Use a thin needle as much as possible.

Thread tension Both the needle thread and looper thread R ed u c e t h e b o t h t h r e a d t e n s i o n s t o a m i n i mum.

tensions are too high.

Throat plate The throat plate has a large needle hole. Replace the throat plate with one with a small

needle hole.

Thread cam timing The thread cam timing is too late Advance the cam timing. Refer to the related

Standard Adjustment.

Feed dogs The leading edge of the feed dog teeth Replace the feed dog.

has been rounded off.

A difference in level exists between the Eliminate such difference in level. main feed dog and differential feed dog.

▼

(Mainly concerned with double chain stitch)

– 58 –

to the next page

Page 63

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

Presser foot pressure The presser foot pressure is not high Increase the presser foot pressure.

enough, providing poor ironing effect.

Differential feed ratio The differential feed ratio has been set for Set it for stretching. When stretching light-weight

gathering. materials, be careful not to cause the presser

foot to contact unevenly with the materials.

Thread amount The looper thread amount is not enough, Bring the thread cam thread guide fully to the

causing excessively tensed stitches. front to increase the amount of looper thread.

– 59 –

From the previous page

Page 64

Part No. of table : 11959400

(Note) All dimensions are in millimeter.

Detailed dimensions of section W-W, section Z-Z, section Y-Y and section V-V

130

1200

54±1

159±1

297

339

291±1

272±1

445

577±1

401

125±1

125

130

(806)

500

600

100

(ø26)

(ø10)

(ø26)

(ø8.5)

37.5

0.5

7.5

11.5

7.5

0.80.8

5x160=800

5-R1

120˚

Detail drawing of measure (2:1)

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

28±1

219±1

37.5

210

116

113±1

203.5

446

390

R30

R15

R10

R30

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

66.5±1

JUKI logotype

450

158

R35

R24

R10

R15

(26)

7. DIMENSIONS OF TABLE

(1) Semi-sunken type

– 60 –

Applicable models MO-6000 Series

Page 65

(2) Semi-sunken type (synchronizer is used)

– 61 –

Applicable models MO-6000 Series

(Note) All dimensions are in millimeter.

Part No. of table : 11959707

130

1200

54±1

159±1

297

339

291±1

272±1

445

577±1

125±1

125

130

(806)

500

600

100

(ø26)

(ø10)

(ø26)

(ø8.5)

37.5

0.5

7.5

11.5

7.5

0.80.8

5x160=800

-R1

120˚

Detail drawing of measure (2:1)

Type : Helvetica Reg. Condensed

Condensed voided letters

Thickness : 1.5

Thickness : 0.8

Thickness : 0.5

Thickness : 1.5

(380)

120

570

42±1

138

281±1

219±1

(37.5)

210

116

113±1

203.5

446

390

(3.5)

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 hoke 26 spot

face 3.5 deep

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

66.5±1

JUKI logotype

450

154

R24

R10

R15

401

R15

R10

R15

36 hole

204

Page 66

(Note) All dimensions are in millimeter.

Part No. of table : 11959558

1200

54±1

159±1

277

25230

184

400±1

150

319

42±1

308

437±1

(426)

107

125

150

(806)

201

350

290

(ø26)

(ø8.5)

ø26

(ø10)

3 7

570

(380)

120

400

160

103

375

281±1

337±1

446

385

223±1

369

113±1

203.5

160

110

66.51

2.5

(14)

(1)

(4)

R30

R15

R10

R30

R10

R16

R34

R15

R10

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

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(3) Fully-sunken type

Applicable models MO-6000 Series

Page 67

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05 · 06 Printed in Japan (E)

This manual uses environment-friendly soyink.

The environmental management system to promote and conduct

the technological and technical research, the development and design of the products in which the environmental impact is considered,

the conservation of the energy and resources, and the recycling, in the research, development, design, distribution, sale and maintenance service of the industrial sewing machines, household sewing machines and industrial-use robots, etc. and in the sale and maintenance service of data entry system and in the purchase, distribution and sale of the household commodities including the healthcare products.