JUKI MB-1373 User manual

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ENGLISH
INSTRUCTION MANUAL

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CONTENTS
1. SPECIFICATIONS ........................................................................................................... 1
2. PREPARATION OF THE SEWING MACHINE ................................................................ 1
2-1. Installation ..........................................................................................................................................1
2-2. Lubrication.......................................................................................................................................... 2
2-3. Attaching the needle..........................................................................................................................2
2-4. Attaching the needle bar cover.........................................................................................................3
2-5. Attaching the button tray assembly .................................................................................................3
2-6. Threading the machine...................................................................................................................... 3
3. ADJUSTMENT OF THE SAWING MACHINE ................................................................. 4
3-1. Thread tension adjustment........................................................................................................................ 4
3-2. Adjustment of the thread pull-off lever .................................................................................................... 4
3-3. Adjusting the tension lever ...............................................................................................................4
3-4. Adjusting the nipper ..........................................................................................................................5
3-5. Adjusting the thread tension guide on the face plate.....................................................................5
3-6. Needle-to-looper relation .................................................................................................................................... 5
3-7. Position of the needle guide ............................................................................................................. 6
3-8. Height of the button clamp................................................................................................................ 6
3-9. Work pressing force ..........................................................................................................................6
3-10.
Adjustment of the button clamp stop lever.....................................................................................6
3-11. Timing of thread tension release ....................................................................................................7
3-12. Setting for 2- or 4-hole buttons....................................................................................................... 7
3-13. Setting a number of stitches........................................................................................................... 8
3-14. Adjusting the position of the stop-motion.....................................................................................8
3-15. Automatic thread trimmer ...............................................................................................................9
(1) Adjusting the position of the moving knife......................................................................................9
3-16. Clearance between the button clamp lifting lever and the adjusting screw .............................. 9
3-17. How to set the L-shaped lifting rod ................................................................................................9
3-18. Knot-tying mechanisms ................................................................................................................10
(1) Adjusting the knot-tying connecting plate..................................................................................... 10
(2) Adjusting the knot-tying arm stopper............................................................................................ 10
(3) Adjusting the knot-tying notch ......................................................................................................10
(4) Changeover of with/without knot-tying ......................................................................................... 11
4. MAINTENANCE, SUBCLASS MODELS AND ATTACHMENTS .................................. 11
4-1. How to connect the metal ttings of the belt ................................................................................ 11
4-2. Subclass models ............................................................................................................................. 11
4-3. Attachments......................................................................................................................................12
(1) Attachments for shank buttons (Pearl buttons) (Z033) ................................................................13
(2) Attachment for the rst process of wrapped-around buttons (Z041)............................................13
(3) Attachment for the second process of wrapped-around buttons (Z035) ...................................... 14
(4) Attachment for snaps (Z037)
........................................................................................................14
(5) Attachment for metal buttons (Z038)............................................................................................ 15
4-4. Motor pulley and belt .......................................................................................................................15
5. TROUBLES AND CORRECTIVE MEASURES ............................................................. 16

– 1 –
1. SPECIFICATIONS
MB-1373 MB-1377
Sewing speed Normal 1,300 sti/min (Max. 1,500 sti/min)
Number of stitches 8, 16 and 32 stitches
Feed amount Lateral feed 2.5 to 6.5mm
Longitudinal feed 0, 2.5 to 6.5mm
Lateral feed 2.5 to 6.5mm
Longitudinal feed 0, 2.5 to 4.5mm
Button size 10 to 28 mm
Needle used TQx1 #16 (#14 to #20) TQx7 #16 (#14 to #20)
Lubricating oil JUKI New Defrix Oil No. 1
Noise -Equivalent continuous emission sound pressure level (LpA) at the workstation :
A-weighted value of 84 dB; (Includes KpA = 2.5 dB); according to ISO 10821-
C.6.3 -ISO 11204 GR2 at 1,300 sti/min.
2-1. Installation
2. PREPARATION OF THE SEWING MACHINE
Put rubber cushion 1on the table,
place the machine head on the rubber
cushion and x it to the table using
screws 2, plain washers 3and nuts
4. Attach “S” chain hook 6and chain
7to stop motion trip lever 5.
1
2
4
3
6
7
5

– 2 –
2-3. Attaching the needle
WARNING :
To protect against possible personal injury due to abrupt start of the machine, be sure to start the
following work after turning the power off and ascertaining that the motor is at rest.
★Use a standard needle of TQx1 #16.
Loosen setscrew 1and hold needle 2with the long
groove facing toward you. Then fully insert it into the
hole in the needle bar, and tighten setscrew 1.
1
2
1
2[Caution at the time of lubricating]
1. Take care not to allow speed slowing friction
wheel 1and friction plate 2to be clogged with
oil to prevent them from the deterioration of
retardation performance. In addition, when the
components are clogged with oil, wipe the oil
from them.
2. Take care not to allow the machine belt to
be clogged with oil to prevent it from the
deterioration.
1
9
2
3
5
67
!1
!0 8
!2
!4
!5
!6
!3
2-2. Lubrication
1) Open the side cover, and apply JUKI New Defrix Oil No. 1 to the
portions shown by the red marks 1to !2 (7: MB-1377 only).
(Apply approximately 1 cc of oil to the respective lubricating
places one to two times a week.)
2) Loosen connecting screw !3, tilt the machine head backward
and apply grease (JUKI designated grease) to crossed helical
gear !5 and worm gear !6.
3) Check, approximately once a week, that oil amount is sufcient
to reach the top of the oil felt placed inside the bed mounting
base. If the amount of oil is insufcient, add an adequate amount
of oil. At this time, also apply oil to crank rod !4.
WARNING :
To protect against possible personal injury due to abrupt start of the machine, be sure to start the
following work after turning the power off and ascertaining that the motor is at rest.
4

– 3 –
2-5. Attaching the button tray assembly
2-6. Threading the machine
Thread the machine head in the order of 1to @1 as shown in the illustration given above. Then, pass the
thread through the needle eye from the front for approximately 60 to 70 mm as you depress nipper releasing
knurled thumb nut A.
* Standard needle is TQ X 1 #16.
1) Loosen screw 2and remove thread guide 3.
2) Place needle bar guard 1under thread guide
3and attach thread guide 3so that lever 4
comes to the center of it at the start of the ma-
chine.
3) Fix the cover with screw 2.
2-4. Attaching the needle bar cover
WARNING :
To protect against possible personal injury due to abrupt start of the machine, be sure to start the
following work after turning the power off and ascertaining that the motor is at rest.
WARNING :
To protect against possible personal injury due to abrupt start of the machine, be sure to start the
following work after turning the power off and ascertaining that the motor is at rest.
Insert the posts of button tray 1in hole on the right
of the machine sub-base and tighten each setscrew
2. If it is difcult for the operator to pick up the but-
tons on the right side, change it to hole 3on the left
side.
1
2
1
2
43
3
1
2
5
6
7
8
9
!3
!1
!2
!6
!4
!5
!9
!7
!8
A
@0
@1
!0
4 3

– 4 –
3-2. Adjustment of the thread pull-off lever
To adjust the thread pull-off lever 1, insert a screwdriver through an opening in the machine arm side cover
(left), loosen screw 2and adjust the position of nipper bar block (rear) 3to the left or the right. If the end of
thread is drawn from arrow hole A in the button after sewing, change the position of nipper bar block (rear) 3
to the left. Move the lever to the right when the thread end comes out from arrow hole B.
3-3. Adjusting the tension lever
1) When the machine is in the stop-motion state,
loosen screw 1.
2) Tighten setscrew 1so that there is a clearance
of 8 to 10 mm as a standard between the end of
thread tension guide 3and end of lever 4.
After the adjustment, make sure that the
thread path is within the slot as illustrated in
Fig. Awhen the machine starts.
If the thread paths do not coincide with each
other, loosen screw 2in the tension thread
guide and adjust it properly.
WARNING :
To protect against possible personal injury due to abrupt start of the machine, be sure to start the
following work after turning the power off and ascertaining that the motor is at rest.
WARNING :
To protect against possible personal injury due to abrupt start of the machine, be sure to start the
following work after turning the power off and ascertaining that the motor is at rest.
A
B
1
2
3
At the time of X
stitching
8 to 10 mm
1
2
4
3
A
3-1. Thread tension adjustment
3. ADJUSTMENT OF THE SAWING MACHINE
1
2Tension post No. 1 1is used to adjust the thread
tension to sew on the button and a relatively low
tension will be enough. Tension post No. 2 2is
used to adjust the thread tension applied to the root
of the button sewing stitches. This tension must be
determined according to the type of thread, fabric
and thickness of the button and must be higher than
that of tension post No. 1 1. Turn the tension nuts
clockwise to increase or counterclockwise to reduce
the thread tension.

– 5 –
3-4. Adjusting the nipper
0.4 to 0.6 mm
1
2
1) Provide a 0.4 to 0.6 mm clearance
between nipper block 2and nipper
1to prevent the nipper 1 from hold-
ing the thread while the machine is in
operation.
2) Loosen screw 3and move nipper bar
block 4 to the right or the left.
3-5. Adjusting the thread tension guide on the face plate
★Adjust the needle-to-looper relation as follows :
1) Depress the pedal fully forward, turn the needle driving pulley in the normal sewing direction by hand to
bring down the needle bar to the lowest position of its stroke and loosen screw 1.
WARNING :
To protect against possible personal injury due to abrupt start of the machine, be sure to start the
following work after turning the power off and ascertaining that the motor is at rest.
WARNING :
To protect against possible personal injury due to abrupt start of the machine, be sure to start the
following work after turning the power off and ascertaining that the motor is at rest.
3-6. Needle-to-looper relation
If the formation of seams at the start of sewing is
failed and the seams are formed on the way even
when the thread pull-off lever is adjusted, turn thumb
nut 1(double nut) to decrease the thread tension.
1
2
2
3
AB
C
5
4
6
2
TQx1
TQx7
4
3
(Adjusting the needle bar height)
2) Adjust the height of the needle bar using the top
two lines engraved on the needle bar 2 for the
TQx1 needle and using the bottom two lines for
the TQx7 needle. Align the upper line Awith the
bottom end face of needle bar bushing (lower)
3and tighten screw 1. At this time, tighten the
screw so that groove Cof the needle faces the
front.
(Looper position)
3) Loosen screws 4and turn by hand the needle driv-
ing pulley until lower line Bof two lines aligns with
the bottom end face of needle bar bushing (lower) 3.
4) By keeping the machine in this state, align looper blade
5with the center of the needle and tighten screws 4.
5) Loosen screws 6and provide a 0.01 to 0.1 mm
clearance between the looper and the needle.
Tighten screws 6.
1

– 6 –
3-10. Adjustment of the button clamp stop lever
When clamp screw 1is loosened in the state of
stop-motion, button clamp jaw levers 3opens/clos-
es with button clamp stop lever 2. Set a button to
the correct position and x button clamp stop lever
2at the position where taking in and out of the but-
ton is easily performed with clamp screw 1.
3-7. Position of the needle guide
Loosen screw 2and provide a 0.05 to 0.1 mm clear-
ance between the needle guide 1and the needle
by moving the needle guide 1to the left or the right
when the needle is in the lowest position.
3-8. Height of the button clamp
1) The standard clearance Abetween the rear side
of the bottom face of button clamp jaw lever 1
and the top surface of feed plate 2is 8 mm at
the position where the machine has stopped after
sewing.
2) To adjust the height of the button clamp unit,
loosen screw 3in the button clamp lifting hook
and move button clamp lifting hook 4up or
down.
3-9. Work pressing force
The standard work pressing force is by providing a
28.5 to 29.5 mm between the top end of nut 1and
the bottom end of pressure adjusting bar 2.
Turn nut 1to adjust it.
WARNING :
To protect against possible personal injury due to abrupt start of the machine, be sure to start the
following work after turning the power off and ascertaining that the motor is at rest.
WARNING :
To protect against possible personal injury due to abrupt start of the machine, be sure to start the
following work after turning the power off and ascertaining that the motor is at rest.
WARNING :
To protect against possible personal injury due to abrupt start of the machine, be sure to start the
following work after turning the power off and ascertaining that the motor is at rest.
WARNING :
To protect against possible personal injury due to abrupt start of the machine, be sure to start the
following work after turning the power off and ascertaining that the motor is at rest.
12
3
4
3
2
1
A
28.5 to
29.5 mm
2
1
1
2
0.05 to 0.1 mm

– 7 –
3-11. Timing of thread tension release
Turn the needle driving pulley as you draw the thread in the direc-
tion of arrow mark A and you will nd a point at which the tension
discs on the tension post No. 2 release the thread. At this moment,
the standard distance from the top end of the needle bar bushing
(upper) to the top end of the needle bar is 44 to 47 mm (in case of
the needle of TQ X 7, 54 to 57 mm).
Perform the following adjustments especially when the undermen-
tioned troubles occur frequently.
Loosen nut 1, insert the blade of a screwdriver to the top slot of
the tension post No. 2 and turn it in the direction of arrow mark B
to lower the height of the thread oating bar and in the opposite
direction to raise the height.
3-12. Setting for 2- or 4-hole buttons
Perform the adjustment after
confirming that the sewing
machine is located at the
position of the stop-motion (refer
to "3-14. Adjusting the position
of the stop-motion", p.8).
Measure the distance between two
holes in a button and set equally cross-
wise and lengthwise feed regulators for
4-hole buttons.
[In case of MB-1373]
★Lengthwise feed
Push down lengthwise feed
adjusting lever 1and set it to
“0” for 2-hole buttons or a cor-
responding amount for 4-hole
buttons.
★Crosswise feed
Loosen nut 2and set sec-
tion Aof pointer 3to a
corresponding amount. Then
tighten nut 2.
Phenomenon Height of thread oating bar
1.When the stitch made on the wrong side of the
workpiece is too loose ;
Make the needle bar slightly higher.
2.When the thread is broken at the time of stop-motion ; Make the needle bar slightly lower.
3.When the thread is broken frequently ; Make the needle bar slightly lower.
WARNING :
To protect against possible personal injury due to abrupt start of the machine, be sure to start the
following work after turning the power off and ascertaining that the motor is at rest.
1
2
3
B C A
1
A
MB-1377
A
[In case of MB-1377]
★Lengthwise feed
Push down lengthwise feed adjusting lever 1and set it to "0" for -2-hole
buttons or a corresponding amount for 4-hole buttons by the respective
procedures below according to the sewing methods.
X stitch : Set the lengthwise feed adjusting lever to the position corre-
sponding to the amount for the button within the range of A.
U-sharp stitch : Set the lengthwise feed adjusting lever to the position cor-
responding to the amount for button within the range of B.
When setting the lengthwise feed adjusting lever to the position of
C (outside of range of setting the lever), not only the sewing cannot
be performed but also trouble will be caused. Do not set the feed
adjusting lever at the position of C.
★Crosswise feed
Loosen nut 2and set section Aof pointer 3to a corresponding amount.
Then tighten nut 2.
Before operating the machine, ensure that the needle enters the
center of each hole in the button.
B

– 8 –
3-13. Setting a number of stitches
To change the number of stitches, open the left-hand side cover and change the number of stitches using
stitch number adjusting screw 1and stitch number adjusting lever 4(optional).
★ How to adjust 8 stitches
In the state of 16 stitches, stitch number adjusting
gear roller 2which is attached to the large gear 5
comes to the lower side, assemble stitch number
adjusting lever 4(supplied as accessories) using
hinge screw 3(supplied as accessories).
When stitch number adjusting screw 1being set for
"8 stitches" has arrived at the left end, loosen stitch
number adjusting screw 1 and x it to the position
as shown in the illustration.
WARNING :
To protect against possible personal injury due to abrupt start of the machine, be sure to start the
following work after turning the power off and ascertaining that the motor is at rest.
1
1
2
4
3
5
To make 8 stitches, loosen stitch number adjusting
screw 1 and x it to the position as shown in the
illustration.
★How to adjust 16 stitches
★How to adjust 32 stitches
2
1
3
4
A
B
3-14. Adjusting the position of the stop-motion
Adjust so that claw 1of the stop-motion cam comes
in contact with stop-motion hook 2when the sewing
machine completes the sewing and stops.
When replacing the motor pulley and
changing the sewing speed from 1,300 sti/
min to 1,500 sti/min, and vice versa, be sure
to re-adjust the position of the stop-motion.
[Adjusting procedure]
• When the stop-motion hook comes in
contact with the stop-motion cam and
rebounds, (When there is a clearance
between claw 1and stop-motion hook 2)
loosen two stop-motion position adjusting
screws 3, turn stop-motion adjusting cam 4
in the direction of A, and x stop-motion posi-
tion adjusting screws 3.
• When the stop-motion hook stops before it
comes in contact with the stop-motion cam claw
Loosen two stop-motion position adjusting
screws 3, turn stop-motion adjusting cam 4
in the direction of B, and x stop-motion posi-
tion adjusting screws 3.

– 9 –
3-15. Automatic thread trimmer
(1) Adjusting the position of the moving knife
When the presser has completely lifted at the stop-
motion position (refer to "3-14. Adjusting the posi-
tion of the stop-motion", p.8), it is the standard
that the clearance between thread trimming con-
necting plate (front) 1and the end face of the slit of
throat plate 2is 10 to 11 mm. To adjust the afore-
mentioned clearance, tilt the machine head, remove
the oil shield, loosen two nuts 3and move connect-
ing screw 4back or forth. When you tighten nuts 3,
ensure that joint 5stays in the horizontal position.
3-16. Clearance between the button clamp lifting lever and the adjusting screw
Provide a 0.5 mm clearance between the end face of
button clamp lifting lever 1and adjusting screw 2
at the stop-motion position (refer to "3-14 Adjusting
the position of the stop-motion", p.8) and tighten
with adjusting screw nut 3.
3-17. How to set the L-shaped lifting rod
Put moving knife push-back spring 2, stop-motion
rubber cushion washer 3, stop-motion rubber cush-
ion 4and stop-motion rubber cushion washer 5, in
this order, to L-shaped lifting rod 1. Make the jaw
of the machine arm come into close contact with the
end face of the stop-motion rubber cushion washer
at the stop-motion position (refer to "3-14 Adjusting
the position of the stop-motion", p.8) and set the
L-shaped lifting rod without a play. Then tighten it
with screw 6.
WARNING :
To protect against possible personal injury due to abrupt start of the machine, be sure to start the
following work after turning the power off and ascertaining that the motor is at rest.
23
0.5 mm
1
2
5
4
3
6
1
1
2
5
43
10 to 11 mm

– 10 –
3-18. Knot-tying mechanisms
(1) Adjusting the knot-tying connecting plate
Loosen screws 1and adjust so that a clearance of
1 to 1.5 mm is provided between the needle 2and
the knot tying plate 3when the roller of the knot-
tying arm gets on the outmost periphery of the knot-
tying notch.
After the adjustment, ascertain that the needle
does not come in contact with the knot-tying
plate.
(2) Adjusting the knot-tying arm stopper
When starting the sewing machine and the roller of
knot-tying arm does not come into contact with the
knot-tying notch, loosen screws 3and adjust with
stopper 4so that outside periphery 1of the needle
hole almost aligns with top end 2of the knot-tying
plate.
(3) Adjusting the knot-tying notch
Loosen screws 1and adjust so that the roller of the
knot-tying arm comes in contact with the knot-tying
notch when the needle bar goes up at the fourteenth
stitch as high as 30 to 35 mm (40 to 45 mm when a
TQ x 7 needle is used) above the needle bar upper
bushing.
If two knot-tying notches are to be installed
(without crossover stitch), make the
aforementioned adjustment at the 6th and
14th stitches.
WARNING :
To protect against possible personal injury due to abrupt start of the machine, be sure to start the
following work after turning the power off and ascertaining that the motor is at rest.
1 to 1.5 mm
2
1
3
2
1
34
30 to 35 mm
1

– 11 –
4. MAINTENANCE, SUBCLASS MODELS AND ATTACHMENTS
4-1. How to connect the metal ttings of the belt
Tighten connecting screws 1of the belt so that the
screws protrude approximately 1.5 to 2 mm from the
reverse side as the standard.
1
1
1
4-2. Subclass models
MB-1373 MB-1373-11
8, 16, 32 stitches 8, 16, 32 stitches
1.5 to 2mm
(4) Changeover of with/without knot-tying
To make “with knot-tying”, pull knot-tying changeover
knob 1toward the front and place it to the position
in the gure.
To make “without knot-tying”, pull knot-tying change-
over knob 1toward the front and place it to the
position in the gure.
1. When assembling the belt to the pulley
and rotating the motor after closing the
side cover, confirm that the side cover
does not interfere with the metal tting of
the belt.
2. Take care not to allow the belt to be
clogged with oil when assembling it.

– 12 –
4-3. Attachments
1) In order to install the attachment on the machine,
you may have to remove button clamp mecha-
nism 1or feed plate 2.
2) Detach the snap ring from button clamp installing
stud 3, and you will be able to remove button
clamp mechanism assembly 1. Remove screw
4, and you can remove feed plate 2.
The only feature that makes the difference
between the attachment of MB-373NS and
that of MB-377NS is button clamp lifting
hook 5.
Use Flat buttons Shank buttons Snaps
Large-size Medium-size General
MB-1373
MB-1377 Z201 Z202 Z033 Z037
Schematic
drawing
Remarks Button size :
A : 3 to 6.5 mm
B : ø20 to ø28 mm
Button size :
A : 3 to 5 mm
B : ø12 to ø20 mm
Button diameter : Less than 16 mm
Shank size :
Thickness : 6 to 5 mm
Width : 3 to 2.5 mm
Snap size :
A : 8 mm
Use Wrapped-around buttons Metal buttons Stay button Labels
First process Second process General
MB-1373
MB-1377 Z041 Z035 Z038 Z039 Z044
Schematic
drawing
Remarks Thread shank height
A : 5.5 mm
Common to
Z041
Stitch width :
3 to 6.5 mm
WARNING :
To protect against possible personal injury due to abrupt start of the machine, be sure to start the
following work after turning the power off and ascertaining that the motor is at rest.
1
2
5
43
A
B
A
A
B

– 13 –
(1) Attachments for shank buttons (Pearl buttons) (Z033)
(INSTALLATION)
Remove both the button clamp mechanism assem-
bly and the feed plate from the machine and install
attachment 1in place. Loosen screws 3and adjust
button clamp bracket 4to permit the needle to
come down in the middle of the needle slot in shank
button adaptor 2. Attach button clamp feed plate 5
using screws 7in the way that it permits the needle
to come down in the middle of the needle slot in feed
plate 6. Insert the top end of button clamp stud 8
into an opening in the jaw of the machine arm and
fasten it by screw 9.
(ADJUSTMENT AND OPERATION)
(2) Attachment for the rst process of wrapped-around buttons (Z041)
1) Loosen screw !2, let feed plate 6recede 0.5 to 1.0 mm from the left end of button clamp jaw lever 2
and retighten screw !2.
2) Set a button in place, loosen screws !3 and !4 and align shank button holding clamp !5 with the center of
the button.
3) Shank button holding clamp !5 must give proper pressure to the button so that the button stays steadily
in position while being sewn. Loosen a setscrew in thrust collar !6 and rotate the thrust collar until shank
button holding clamp !5 provides proper pressure.
4) You may x button clamp block !7 in a convenient position for operation.
1. When you x the thrust collar, ensure that button clamp rotating shaft !8 does not play axially in its
bracket.
2. Adjust lifting hook @0 and stopper pin !1 so that L-shaped lifting rod roller !9 does not come in
contact with button clamp bracket 4.
WARNING :
To protect against possible personal injury due to abrupt start of the machine, be sure to start the
following work after turning the power off and ascertaining that the motor is at rest.
WARNING :
To protect against possible personal injury due to abrupt start of the machine, be sure to start the
following work after turning the power off and ascertaining that the motor is at rest.
(INSTALLATION)
Attach wrapped-around button foot 1to the ordinary
button clamp jaw levers using screw 2and guide
pin screw 3.
Align foot 1with the jaw levers so that they permit a
button to rest in the middle.
(ADJUSTMENT AND OPERATION)
Adjustment and operation are almost same as those
for the at buttons, but you must adjust the thread
pull-off lever to provide more amount of thread in
order to make the thread loose below the button for
thread shank formation. (refer to "3-2.
Adjustment of
the thread pull-off lever ", p.4)
1
2
4
3
67
89!0 !1
!2
!3
!4
!5
!6
!7
!8
!9
@0
5
1
2
3

– 14 –
(3) Attachment for the second process of wrapped-around buttons (Z035)
(INSTALLATION)
Remove the button clamp mechanism assembly, but-
ton clamp pressure adjusting bar and feed plate from
the machine and install attachment for the second
process of wrapped-around buttons 1. When you
install a Z035 attachment, you must remove also the
L-shaped lifting rod.
Insert moving knife push-back spring 3, washer
4, cushion 5and washer 4in spring guide shaft
2in this order. Make certain that the stop-motion
mechanism has completely engaged, and install the
attachment assembly in place in the way that cush-
ion 5comes in close contact with the surface of the
machine arm without play.
(ADJUSTMENT AND OPERATION)
1) Loosen screw 6and adjust the thread shank length by moving guide (large) 7and guide (small) 8in
line with the point of needle entry.
2) Set a button (tilt it slightly for easy insertion) and pass the thread as the arrow shows.
3) Set the lengthwise feed to “0”.
(4) Attachment for snaps (Z037)
(INSTALLATION)
Remove the button clamp mechanism assembly
and the feed plate. Set both the crosswise feed and
lengthwise feed graduated plates to “4 mm”. Install
snap clamp feed plate 1in the way that the needle
drops evenly at four corners of its square opening.
Install snap attachment assembly 2on the machine,
place a snap on the snap clamp jaw levers and make
sure that the needle drops accurately in each hole in
the snap. If necessary. loosen hex head screws 3
and adjust the position accurately. Lastly, make sure
that the concave section on the bottom face of snap
clamp slide guide 4accurately matches the convex
section on snap clamp feed plate 1.
WARNING :
To protect against possible personal injury due to abrupt start of the machine, be sure to start the
following work after turning the power off and ascertaining that the motor is at rest.
WARNING :
To protect against possible personal injury due to abrupt start of the machine, be sure to start the
following work after turning the power off and ascertaining that the motor is at rest.
1
(Z035)
2
5
43
1
2
4
3
7
86

– 15 –
(5) Attachment for metal buttons (Z038)
(INSTALLATION)
Remove both the button clamp mechanism assem-
bly and the feed plate from the machine and install
attachment 1in place. Loosen screws 3and adjust
button clamp bracket 4to permit the needle to
come down in the middle of the needle slot in metal
button adaptor 2. Attach button clamp feed plate 5
using screws 7in the way that it permits the needle
to come down in the middle of the needle slot in feed
plate 6. Insert the top end of button clamp stud 8
into an opening in the jaw of the machine arm and
fasten it by screw 9.
(ADJUSTMENT AND OPERATION)
1) Loosen screw !0, let feed plate 6recede 1.0 to 1.5 mm from the left end of button clamp jaw lever 2
and retighten screw !0.
2) Set a button in place, loosen screws !1 and !2 and align metal button holding clamp !3 with the center of
the button.
3) Metal button holding clamp !3 must give proper pressure to the button so that the button stays steadily
in position while being sewn. Loosen a setscrew in thrust collar !4 and rotate the thrust collar until metal
button holding clamp !3 provides proper pressure.
4) You may x button clamp block !5 in a convenient position for operation.
1. When you x the thrust collar, ensure that button clamp rotating shaft !6 does not play axially in its
bracket.
2. Adjust lifting hook !9 and stopper pin !8 so that L-shaped liting rod roller !7 does not come in
contact with button clamp bracket 4.
4-4. Motor pulley and belt
1) For this machine a single-phase or 3-phase 200 watts (1/4 HP) induction motor is used.
2) Use a V belt.
3) The sewing speed depends on the diameter of the motor pulley as listed below ;
★The pulley of 50Hz and 1,300 sti/min is in common with that of 60Hz and 1,500 sti/min.
★The rotating direction of motor is counterclockwise when viewed from the motor pulley side.
Be careful not to rotate in reverse direction.
★When replacing the motor pulley and changing the sewing speed from 1,300 sti/min to 1,500 sti/min and
vice versa, be sure to re-adjust the position of the stop-motion. (Refer to "3-14. Adjusting the position
of the stop-motion", p.8.)
Hz sti/min Motor pulley part No.
50
1,500 40038291 ø 76
1,300 40038298 ø 64.5
60
1,500 40038298 ø 64.5
1,300 40042229 ø 57
mm
WARNING :
To protect against possible personal injury due to abrupt start of the machine, be sure to start the
following work after turning the power off and ascertaining that the motor is at rest.
1
2
5
4
3
7
89
!0
!1
!2
!3
!4
!5
!8
!9
6
!6
!7

– 16 –
5. TROUBLES AND CORRECTIVE MEASURES
TROUBLES CAUSES CORRECTIVE MEASURES
1.
Thread breakage 1The yoke slide does not move in the correct
way.
™Adjust the timing of forward, backward and
sideways of the yoke slide.
2The tension lever has been improperly
adjusted.
™Properly adjust the tension lever.
3The thread tension post No. 2 fails to release
the thread at correct timing.
™Make the thread release timing slightly earlier.
4Lifting amount of the button clamp jaw unit is
excessive.
™Adjust the lifting amount of the button clamp jaw
lever to 8 mm.
5The thread nipper catches the thread.
The nipper has been improperly adjusted.
(The clearance is too small.)
™Adjust the position of the nipper bar block.
6The needle does not enter the center of the
holes in the button.
™Adjust the button clamp jaw lever holder.
7The needle is too thick for the diameter of the
hole in the button.
™Replace the needle by a thinner one.
2. The machine forms a
seam after it has run for a
while instead of forming it
from the start of sewing.
1The thread pull-off lever has been improperly
adjusted.
™Adjust the thread tension guide on the face plate
so that it provides a lower tension.
2Tension of the thread tension guide on the
face plate is excessive.
™Properly adjust the tension lever.
3.
Buttons are not sewn
tightly
1The yoke slide does not move in the correct
way.
™Adjust the timing of the motion of the yoke slide at
each end.
2The thread tension post No. 2 fails to release
the thread at correct timing.
™Make the thread release timing slightly later.
3The thread tension post No. 2 does not give
sufcient tension.
™Tighten the tension nut of tension post No. 2.
4The needle does not enter the center of the
holes in the button.
™Adjust the button clamp jaw lever holder.
5
The work pressing force is too high or too low.
™Adjust the work pressing force properly.
4.
The last back-tack stitch
is poorly tensed.
1The tension lever has been improperly
adjusted.
™Properly adjust the tension lever.
2Timing of the knot-tying plate is incorrect. ™Advance the timing of the knot-tying plate.
(Adjustment of the knot-tying notch)
3The nipper has been improperly adjusted.
(The clearance is too large.)
™Adjust the nipper with the nipper bar block.
5. The rst stitch trails
relatively long thread
from the right side of the
button.
The thread pull-off lever does not work properly. ™Adjust the thread pull-off lever by the nipper bar
block (rear).
6.
Thread trimming failure
in the state of stop-
motion
1The thread tension post No. 2 fails to release
the thread at correct timing.
™Make the thread release timing slightly later to
give more tension to the stitches.
2The needle hits the edge of the holes in the
button.
™Adjust the button clamp jaw lever holder.
3The thread nipper fails to press the thread. ™Adjust the nipper bar block.
4The work pressing force is too high. ™Adjust the work pressing force by the pressure
adjusting nut.
7.
Thread trimming failure 1The moving knife does not separate the
thread on the fabric with its separation nail.
™Adjust the position of the moving knife.
2The needle does not enter the center of the
holes in the button.
™Adjust the button clamp jaw lever holders.
3The last stitch skips. ™Adjust the looper.
4The moving knife thread separation nail is too
high or too low.
™Adjust the height of the moving knife thread
separation nail.
8.
The needle thread is
cut in two places on the
wrong side of the fabric.
1The moving knife is set in wrong place. ™Adjust the position of the moving knife when the
machine is in the stop-motion state.
2The moving knife thread separation nail is too
high or too low.
™Adjust the height of the thread separation nail.
9.
Button trails too long
thread after thread
trimming.
1Timing of the moving knife motion is wrong. ™Adjust the position of the moving knife.
when the machine is in the stop-motion state.
2Lifting amount of the button clamp jaw unit is
excessive.
™Adjust the lifting amount of the button clamp jaw
lever to 8 mm.
10.
Length of thread
remaining, after thread
trimming, on the wrong
side of the material
varies.
1Position of the moving knife is not correct. ™Adjust the position of the moving knife when the
machine completes stop-motion. (10 to 11 mm)
2Lifting amount of the button clamp jaw unit is
excessive.
™Adjust the lifting amount of the button clamp jaw
lever to 8 mm.