JUKI MO-804 User manual

MODEL
MO-804
SUPER SPEED SINGLE NEEDLE OVEREDGING
INDUSTRIAL SEWING MACHINE
MODEL
SUPER SPEED TWIN-NEEDLE OVEREDGING
INDUSTRIAL SEWING MACHINE
MODEL
SUPER SPEED SAFETY STITCH
INDUSTRIAL SEWING MACHINE
Instruction Book
CLASS
MO-814
MO-816
TOKYO JUKI INDUSTKIAL CO.. LTD.
From the library of: Superior Sewing Machine & Supply LLC

FIRST OF ALL
We thank you for purchasing JUKI MOSOOSeries machines.
Before operating this machine, please read and digest the contents of the INSTRUCTION BOOK thoroughly and
understand the functions
of the machine and cherish it everlastingly.
SPECIFICATIONS
MO-804-DD4 MO-814-BD4
MO-816-DD4
Sewing speed Up to 7,500 s.p.m. Up to
7,000 s.p.m. Up to 6,500 s.p.m.
Stitch length
0.3 - 4 mm(l/64"-5/32")
Needle gauge
2.0mm(5/64")
3.2mm(l/8")
Overedging width
3.2mm(l/8")
Ratio of differential feed
Gather sewing: 1:2 (Max. 1:4)
Stretch sewing: 1:0.7 (Max. 1:0.6)
Needle
DCx27 (Standard)
DCxJ27 (In case of fine synthetic thread)
Needle bar stroke
24.2 mm(61/64")
Lubricating oil
New Defrix Oil No. 2
* Manyother subclassmachinesare availableto meet all kinds of sewingrequirements.
5.
6.
7.
8.
9.
III.
1.
2.
3.
4.
5.
6.
7.
8.
IV.
V.
CONTENTS
HOW TO INSTALL THE MACHINE 1
How to install the thread stand, complete 1
How to install
the frame support plate 1
Motor pulley and the belt 2
How to install the head 2
Starting pedal and presser foot lifting pedal 2
HOW TO OPERATE THE MACHINE 3
Cautions on operation 3
Lubrication and drainage 3
How to install the needle 3
Threading the machine 3
MO-804 4
MO-814 5
MO-816 6
The thread tension 7
Presser foot and feed dog 7
Adjusting the stitch length 8
Adjusting the differential feed 8
Adjusting the differential feed ratio 9
ADJUSTING THE MACHINE 9
Knife and overedging width 9
Adjusting the needle guard 10
Adjusting the height
of the needle 11
Matching the lower looper 11
Matching the upper looper 11
Matching the double chain looper (In case of MO-816) 12
Adjusting the chain looper thread cam (In case of MO-816) 12
Adjusting the double chain looper avoiding motion (In case of MO-816) 12
MAINTENANCE OF THE MACHINE 13
CAUSES OF MALFUNCTIONS &CORRECTIVE MEASURES 13
SPECIFICATIONS (Applicable to all models) 13
From the library of: Superior Sewing Machine & Supply LLC

I. HOW TO INSTALL THE MACHINE
1. How to install the thread stand, complete
Install the thread stand, complete as shown in the flgure and set it to the table.
—
2. How to install the frame support plate
Vibration absorbing rubber
Oil reservoir Cloth wastechute, upper
support
Cloth waste chute, upper
Set screw
Cloth waste chute, lower
Frame support plate
1) First, install the oil reservoir support post and the-waste
cloth chute (upper) to the frame support plate as shown in
the figure.
2)
Attach the waste cloth chute (lower) to the waste cloth
chute (upper) at an appropriate position. The installing length
can be adjusted within the area of 40 mm(i-37/64").
Bushing
m
Table
Bolt -
i. a
E
Oil reservoir
X•
"T" Nut lower
Bolt tip surface
Frame support
plate
3) Height of the frame support plate
A. In case of semi-sunken type table, match
the end surface of the bolt with the
lowersurface of the end part of the nut.
In this case, insert the frame support
bushing to the frame support plate.
esa
— Bolt
M^
Nut
J^Washer
Cut it off
Frame
'support
plate
5mm(3/i6")
v^CLoth plate
Oil reservoir
I
Bolt cap Prame support plate
This can be applied to sunken type table B. In case of fully-sunken type, make the
iJso. upper surface of the cloth plate 5 mm
Also, cut off the end of the bolt which (3/16") higher than the table surface,
is sticking out from the nut.
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3. Motor pulley and the belt
When connected directly to the power source,
use an electric clutch motor of 3-phase 1/2 HP
(400 W). The dimensions of the motor pulley
and the belt (M type) are shown in the table
below.
Number of
rotation of
machine
(s.p.m.)
50 Hz
60 Hz
Motor
pulley
P.C.D.
(mm)
M-type belt
(inch)
Motor
pulley
P.C.D.
(mm)
M-type belt
(inch)
Desk
type
All-
sunken
type
Desk
type
All-
sunken
type
5,000
105 36 32 90
34
30
5,500
115 38 32
100
36
32
6,000
125 38
34
110
36
32
6,500
135
38
34
120
38
32
7,000
145
40
34
125
38
32
7,500
155 40 36
135
38
34
(Note)The dimension of the motor pulley isshownin P.C.D. system(outer diameteris P.C.D. + 5.5 mm) and the M-belt dimensionin inches.
4. How to Install the head
Vibration absorbmg .11
rubber jB:'
1
Frame support plate
Oil reservoir
2 support
I. When installing the machine head, insert the vibration absorb
ing
rubber to the hole of the oil reservoir.
5. Starting pedal and presser foot lifting pedal
Starting pedal
Presser foot
lifting pedal
Install the starting pedal to the left side and the presser foot
lifting pedal to the right sideas you face the flgure.
Direction of
rotation
/a
Hand wheel
Guideplateset
screw V—
2. Loosen the belt guide plate set screw and put the belt on.
When
the belt is put on, lower the guide plate to the bottom
and tighten the set screw.
Presser foot lifting lever
S-shaped hook
Cjiain
Attach the chain of the presser foot lifting pedal to the hole at
the top of the presser foot lift lever by hooking it up with a
S-shaped hook as shown in the figure.
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n. HOW TO OPERATE THE MACHINE
1. Cautions on operation
O Do not, under any circumstances, start the machine before filling up the oil reservoir.
e The rotational direction of the machine is clockwise as viewed from the pulley side. Do not run the machine in the reverse direction
because if you do, the lubrication pump will not function and will invite scorching of the machine.
2. Lubrication and drainage
O Use JUKI Defrix Oil No. 2 for lubrication.
Remove the oil cover, attach the funnel in the accessories box
and pour in JUKI Defrix Oil No. 2 until the top of the oil
float indicator reaches the top line of the oil sight window.
After filling up, cover up the oil cover.
0 Inspect the oil sight window every day before operating the
machine. If the oil level falls below the lower line, fill it up
to the upper line.
0 To drain out the oil, remove the oil drainage screw.
(Caution)
O When the machine is to be operated for the first time or when
it was idle for a long period of time, be sure to oil the top
of the needle clamp guide bar @ and the top part of the
upper looper guide 0 before starting the sewing operation.
0 As the lower knife slide shaft © moves slightly during the
running of the machine, apply a small amount of oil to the
oiling hole 0 at the upper part of the lower knife installing
body.
0 If any oil other than designated oil is used, it might invite
scorching or oil leakage. Be sure to use only the designated
JUKI New Defrix Oil No. 2.
Oil drainage screw
0
Lubricating hole
Upper line
Lower line
3. How to Install the needle
The standard needle size for both overlock, double chain or for left overlook (MO-816 or MO-814) is DC x 27 #11.
To install the needle:
O Rotate the pulleyand raise up the needleclamp to the highest position.
0 Loosen the needle clamp screw , insert the needle and push it up deep into the needle hole untilit stops and tighten the screw.
0 Insert the needle so that the grooved part of the needle is facing the opposite side as seen from the front of the machine.
©
MO-804
MO-8I4-816
4. Threading the machine
Refer to the accompanying figure for correct threading of this machine series.
- 3 -
c
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MO-804
1. Ovcrlock needle iliread is No. 1 and is shown in red color.
2. Upper looper thread is No. 2 and is shown in blue color.
3. Lowerlooper thread is No. 3 and isshown in yellowcolor.
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MO-814
1. Left side needle thread is No. 1 and is shown in red color.
2. Right side needle thread is No. 2 and is shown in green color.
3. Upper looper thread is No. 3 and is shown in blue color.
4. Lower looper thread is No. 4 and is si. own in yellow color.
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a
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MO-816
1. Overlock needle thread is No, I and is shown in red color.
2. Double chain needle thread is No. 2 and is shown in green color.
3. Upper looper thread is No, 3 and is shown in blue color.
4. Lower looper thread is No, 4 and is shown in yellow color.
5. Double chain looper thread is No, 5 and is shown in black color.
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Q)
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5. The thread tension
The thread tension varies according to the kinds of sewing material, thickness and kinds of sewing thread, overedging width, stitch
length and etc. and therefore the pressure of the thread tension disc must be adjusted in each individual case.
MO-804
MO-814
MO-816
(1) Overlock needle threadshouldbe adjusted by tension knob 0 .
(2) Upperlooper thread should be adjusted by tension knob® .
(3) Lowerlooper thread should be adjusted by tension knob @ .
(4)Double chain needle thread or left side overlockneedle thread should be adjusted by tension knob @ . (In case of MO-816 or MO-814)
(5) Double chain looper thread should be adjusted by tension knob (5). (In case of MO-816)
0 ® ©
6. Presser foot and feed dog
(1) The pressure ofthe presser footis adjustediby rotating the presser foot adjusting screw 0 . The standard pressure is4.5 kg. (9.9 lbs)
* When the presser foot is to be turned sideways, knock down the presser lifting lever ® to the rear. When the presser foot isreturned
to the original position, be sure to knock down the presser lifting lever toward front.
(2)Thestandard protrusion of the feed dogfrom the throat plate surfaceis 0.8 mm(l/32").
For heavy weight materials, makethe protrusionamount bigger and for lightweightmaterials makeit less.
The protrusion amount can be adjusted by the feed dog set screws (D and 0 . When making this adjustment, be sure that the
height ofthe main feed dog 0 and thesub feed dog ® becomes equal. The auxiliary feed dog 0 should be installed 0.5 mm(l/64")
lower than this height.
8) CIQ
(3) Adjusting the slanting of the feed dog
Remove the rearside cover of the machine. Then, remove the rubbercap and loosen the set screw 0 . If a roundbarisinserted into the
hole ® of the eccentricshaft (D and rotated, the slanting of the feed dog canbe adjusted. Afteradjustment, tighten theset screw (f).
Also, in so doing, loosen the screw ® and move the thrust collar sothat the screw of the feed barshaftthrust collar (Q) coming out
from the hole of the feed mechanism cover, comes directly overhead.
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(4) Unless the bottom surface of the presscr foot ® and the upper surface of the throat
plate are snuggly contacting each other when the feed dog is lowered, the stitches may
become curved and the chain-off thread stitching of double chain stitch can not be
performed well. Loosen the presser foot hinge screw © and adjust so that the bottom
surface of the presser foot ® drops little to right when the presser foot is raised and
when the presser foot is lowered, the bottom surface snuggly contacts the throat plate
surface. (In case of MO-816)
(Note)
* When sewmg light weight materials, if the pressing pressure is too strong or the protrusion amount of the feed dog is too great, shrink stitch-
irig or damage to the sewing cloth may result. On the contrary, if the pressure is too weak or the protrusion of the feed dog is too small,
pitch flaw or contracted stitches might result. Be sure to make correct adjustment.
7. Adjusting the stitch length
The stitch length can be adjusted by changing the eccentric amount of the feed cam.
\i
/ csT
Indicating
(1)As you keep pushing the push button (T) with your finger,
rotate the pulley toward the desired direction. You will hear
a "click" sound and the push button will enter deep inside.
(2) As you keep pressing the
button, match the stitch length which
is carved in the pulley with the indicating point of the frame.
(3) The figures carved in the pulley indicate the stitch length.
If the figure
"3" of the pulley is matched with the indicating
point of the frame, the stitch length becomes approximately
3 mm.
8. Adjusting the differential feed
Tlie differential feed ratio is adjusted by changing the moving range
of the-sub feed. If the differential feed lever ® is pushed up, gather
stitching can be performed and if it's moved downwards, stretch
stitching can be performed.
(1)Push the sub feed stopper lever (2) toward the frame direction,
and rotate it towards the reverse direction of the arrow until it
stops.
(2) Loosen the differential feed lock nut (3) and by moving the
differential feed lever ® either up or down, adjust to the desired
differential feed amount. After adjustment, tighten the differential
feed lock nut (3).
(3) Next, push the sub feed stopper lever (2) toward the frame
direction and rotate it toward the arrow direction until it stops.
(The cam which is inside will rotate and sets it).
* The subclass machines, which can adjust the differential feed by
the knee during the running of the machine, are also available.
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(D
n
Gather stitcl^^^
Stretch stitching
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9. Adjusting the differential feed ratio
The standard differential feed ratio of this machine is :
Gatherstitching 1:2 Stretchstitching 1:0.7
When this standard differential feed ratioisto be changed dueto change of sewing conditions, adjust as follows :
1) Remove the cover (l) on the back of the machine.
2) Loosen the main feed arm pin setting nut (2).
3) Ifthe main feed arm pin (3) is moved up and down, the differential feed ratio changes as follows :
(1) When the mainfeed arm pin israisedto highestpoint, the differentialfeed ratio becomes:
Stretchstitching 1:0.6 Gatherstitching 1:1.7
When the mainfeed arm pin isloweredto lowestpoint, the differentialfeed ratio becomes:
Gather stitching 1:4
When the differential feed ratioisto be changed to the standard differential feed ratio(stretch stitching 1:0.7, gather stitching
match the center ofthenut @ with the carved line ofthe main feed arm (J).
(2)
(3)
if)
1:2),
Maximum differential feed ratio
for stretch stitching
Maximum differential feed ratio
for gather stitching
Throat plate
I
ni. ADJUSTING THE MACHINE
1. Knife and overedging width
(1) On the lower knife
Loosen the lower knife set screw (D and insert the lower knife
(3) into the groove of the lower knife slide shaft (2) as shown
in the figure. Make the tip of the lower knife the sameheightas
the surface of the throat plate and tighten the lower knife set
screw 0
//////////////.
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Lower
knife
/tlA tiA n ft A
0
m
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(2) On the upper knife
To install the upper knife, push the lower knife slide shaft (D to the
left side and tighten the set screw (2).
O Loosen the upper knife set screw (3) and insert the upper knife @ into
the upper knifesupport (D.
@ Make the width of knife (dimension from needle position to the upper
knife) little less than the desired overedging width and lightly stop the
upper knife by the upper knife set screw from above the upper knife
presser (6) and the upper knife guide (7) .
® Next, rotate the pulley and when the upper knife has risen to the topmost
position, adjust so that the tip of the upper knife comes to 1.5 mm(l/16")
below the lower knife.
O When the adjustment is completed, securely ti^ten the upper knife set screw.
@ Loosenthe lowerknifeslideset screw (2) .
® Rotate the pulley by hand and verify that the knives are not touching the
throat plate or the waste cloth cover.
* When sewing heavy weight materials, be sure to re-tighten the lower knife
shaft set screw (2).
(3) Adjusting the lower knife spring pressure (Refer to sketch below)
Loosen the nut (Z) and adjust by the screw (8),
When the overedging width is wide-j
In case of heavy weight materials^
When the overedging width is narrow-, ,
In noon ni- unuT »• 1.* * • 1 r""Loosen screw
In case of light weight matenals-'
When the adjustment is completed, tighten nut (7).
(4) Overedging width
The standard overedging width is 3.2 mm(l/8") but overedging width of 6.35 mm(l/4") is available as a subclass,
is slightly larger than the width of knife)
•Tighten screw
(The overedging width
2. Adjusting the needle guard
2 needle guards (§) (g) axe attached to the Model MO-804 and
Model MO-814.
1) Loosen screw (D and by moving the needle guard® to right
and left, adjust as shown in the figure.
2) Then, when the needle has dropped to the lowest position,
adjust the front and rear slanting of the needle guard ® so
that the needle barely touches the needle guard. Then tighten
screw (D .
3) Adjust the needle guard (g) by loosening the screw (2) and
adjust in the same manner as the needle guard ® (MC)-814
needle guard is (F)).
4) For MO-816, adjust the needle guard © with screw ® and
the needle guard (g with screw @ by matching, respectively,
with the double chain needles.
5) The up and down height of the needle guard ® needle guard©
and needle guard ©(MO-816) and the slanting angle of these
guards should be adjusted, respectively, by loosening the screw®
and screw (?).
I.Dmm
2.5mm
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Needle
Double chain
needle
Overlook
needl6
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3. Adjusting the height of the needle
When the needle clamp is at the topmost position,
the height of the overlook needle is 10 mm(25/64")
from the surface of the throat plate.
4b Matching the lower looper
(1) Standard radius .... 66.5mm(2-5/8")
Loosen the set screw (D and adjust so that the
standard radius (distance from the shaft center
to the blade point of looper) of the blade point
of the lower looper ® comes to 67mm
(2-41/64").
(2) Fore and aft slant 2 mm(5/64")
Adjust so that the fore and aft slant of the
lower looper comes to 2 mm(5/64") and
lightly tighten screw (D.
(3) Clearance between the looper and the needle
Standard thread 0.05-0.1 mm
Fine synthetic thread . . . under 0.05 mm
Loosen the set screw @ , move the lower
looper support arm (2) fore and aft and
adjust so that the clearance between the blade
point of lower looper and back side of the
needle comes to the ibove dimension.
(4) Returning amount of lower looper
MO-804-0D4^ ^
MO-814-BD4 J 4mm(5/32 )
MO-816-DD4 6 mm(15/64")
Next, when the lower looper comes to the
extreme left position, adjust so that the distance
between the blade
point of looper and the
center of the needle (returning amount) comes
to the above distance by loosening the screw
® and (D
5.
Matching the upper looper
(1) Height of upper looper .... llmm(7/16")
When the upper looper (D comes to the
extreme left position, loosen the upper looper
support arm set screw ® and adjust so that
the distance between the looper blade point
and the throat plate surface comes to 11mm
(7/16").
(2) Next, when the upper looper is rising, adjust
so that the clearance with the back surface of
lower looper (2) comes to about 0.1 mm
and lightly tighten screw @
(3) Protruding amount of upper looper...4mm(5/32")
When the upper looper comes to the extreme
left position, adjust so that the distance be
tween the blade point of looper and the center
of the needle becomes 4 mm(5/32") by loosen
ing set screw (3)
(4) At this time re-verify that the distance between
the blade point of the upper looper and the
throat plate surface is 11 mm(7/16") and then
securely tighten the set screw (3) and set
screw @
(5) Lastly, be absolutely sure that the upper looper
is correctly matched and it is not touching
the needle or lower looper.
l0min(2S/64")(MO-804)
In case of single needle
10tnm( 25/64") (MO-814)
u
10mm(25/64")<MO-8I6)
I
In case of twin needles
J ® /
W 2 mm
®—
(D-n
(4>i
fjj^\
Overlook needle —
j 4mm(5/32")
h- (804-814) ^
6mm(15/64') Q
Lower looper
\ 0 .05—0 .limn
• ~ ±
—r
4 mm Jto" )
f
0/
(3)
— Needle / ^
11mm \
\ \
\ \
1 Throat plate
1
0
0 J
0
- 11 -
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6. Matching the double chain looper (In case of MO-816)
O Loosen the double chain looper set screw (l)
and
A: Adjust so that the standard radius of the
double chain looper (2) becomes 64.5 mm
(2-17/32") (as high as possible as long as it
doesn't touch the feed dog).
B: Adjust so that it slants 1.5 mm(l/16") as
viewed from top and lightly tighten the set
screw ®
Next, loosen the set screw (3) and adjust so
that:
A: When the double chain looper (2) moves
from left to right, the clearance between the
blade point and backside of the needle becomes
0.05—0.1 mm.
B: When the double chain looper has reached
the extreme left position, the distance between
the blade point and the center of the needle
becomes 2.5mm(3/32") by adjusting the double
chain looper support arm ® . Then, tighten
the set screw lightly.
When all of the above adjustments are com
pleted, verify that the double chain looper ®
moves from left to right and when the hole
at the tip
of the double chain looper comes to
the center of the needle that the hole of the
double chain looper and the needle eye meet
each other as viewed from the top of the slant.
Then, securely tighten the set screws (D and (3).
Double chain looper
7. Adjusting the chain looper thread cam
(in case of MO-816)
When the needle has reached its highest position,
adjust so that the right comer of the straight line
part of the chain looper thread cam (2) matches
with the
upper surface of the chain looper thread
guide (D . Loosen the chain looper thread cam
screw (D and adjust the cam.
8. Adjusting the double chain looper
avoiding motion (MO-816 Series)
Depending on the size and number of needle,
the double chain looper avoiding motion can be
changed as follows:
1. Fore and aft looper avoiding motion
0.05—0.1mm
Looper avoiding motion Number of needle
For heavy weight materials
(MO-816-DH6, FF6 Series)
2.80 - 3.06 mm
#14 - #21
For standard weight materials
(MO-816-DD4 Series)
2.64 - 2.85 mm
#7 - #16
2. Adjusting method
O Remove the cover (D in the back of machine.
@ Loosen the screw®of the chain looper shaft slide arm.
0Insert a bar of 2 0 into the hole oKBand rotate it.
Whenthe mark©is in front looper avoidingmotion is least
When the mark©is in the
opposite side looper avoiding motion is
greatest
O After adjustment, securely tighten screw®
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5mm ( I/I6')
^Needle
2.5mm
Double chain looper
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IV. MAINTENANCE OF THE MACHINE
O As the knife of the machine cuts the cloth, much waste cloth will be produced, so clean the machine at least once a day.
Dust and thread hards are liable to be collected especially in the clearances of the throat plate, needle guard aMl feed dog, so remove the
throat plate and clean it thoroughly at least once a week.
0 Inspect the machinehead at least oncea year and operate the machinein perfectly maintainedcondition.
V. CAUSES OF MALFUNCTIONS AND CORRECTIVE MEASURES
No. Malfunctions
Reasons
Corrective measures
1. Needle
breaks
(1) Wrong needle
(2) Wrong size number needle used
(3) Needle installed wrong
(4) Needle is curved
(5) Wrong relation with needle guard
(6) Wrong relation with needle & looper
(1) Use only the designated needle
(2) Use needle which fits thickness of cloth and using thread
(3) Refer to chapter on "How to install the needle"
(4) Exchange with new needle
(5) Adjust the needle guard
(6) Refer to the chapter on "Matching the looper"
2. Inadequate
cutting of
knives
(1) Inadequate installation of upper and lower
knives
(2) Knives are worn out
(1) Refer to the chapter on "Knife and overedging width"
(2) Sharpen the lower knife and exchange the upper knife
3. Stitches
skip (1) Relation
of needle with looper
(2) Knife point of looper is blunted
(3) Needle thread is right twist
(4) Inadequate adjustment of thread tension
(5) Inadequate adjustment of chain looper
thread cam (MO-816)
(1) Refer to the chapter on "Matching the looper"
(2) Sharpen with oil whetstone or exchange it with new looper
(3) Change it to left twist thread
(4) Refer to chapter on "The thread tension"
(5) Refer to the chapter on "Adjusting the chain looper thread
cam"
4. Thread
breaks
(1) Inferior quality of thread
(2) Thread is thicker than needle
(3) Inadequate installation of needle
(4) Thread tension is too strong
(5) Needle, looper, throat plate, needle guard
bruised
(1) Use good quality thread
(2) Change to appropriate needle or thread
(3) Refer to the chapter on "How to install the needle"
(4) Adjust by thread tension nut
(5) Sharpen by oU whetstone or buffer
5. Inadequate
chain-off thread
of double
chain stitch
(MO-816)
(1) Inadequate installation of presser foot
(2) Rattle of rear presser foot
(3) Inadequate timing of looper thread cam
(4) Inadequate installation
of double chain
looper
(1) Refer to chapter on "Presser foot and feed dog"
(2) Adjust to eliminate rattle
(3) Refer to chapter on "Adjusting the looper thread cam"
(4) Refer to chapter on "Matching the double chain looper"
6. Wrinkled
stitches
(1) Needle is too thick
(2) Thread tension too strong
(3) Pressing pressure is either too stong or too
weak
(4) Feed dog protruded too much
(5) Knife does not cut well
(6) Differential feed is not matched
(1) Use needle appropriate to cloth and thread
(2) Adjust by thread tension nut
(3) Adjust the pressure by turning the adjusting screw either to
right or left
(4) Lower the feed dog and match the height of the main feed
dog with the height of sub feed
(5) Resharpen the knife
(6) Refer to chapter on "Adjusting the differential feed"
7. Uneven
stitches
(1) Flaw in the thread tension
(2) Inadequate thread tightening
(3) Needle
point is blunted
(4) Inadequate pressing pressure
(5) Inadequate height of feed dog
(1) Use uniform size thread. Clean up the thread path
(2) Strengthen the thread tension
(3) Exchange the needle with a sharp pointed needle
(4) Refer to chapter on "Presser foot and feed dog"
(5) Refer to chapter on "Presser foot and feed dog"
SPECIFICATIONS(Applicable to all models)
Stitch length:
Differential feed
ratio:
Lower knife
pressure:
Overedge width:
Presser lifting
amount:
Needles:
Needle bar stroke:
Upper looper:
Double chain
stitch mechanism:
Presser foot:
Lubrication:
0.3-4.0mm(l/64"-9/64") (Push-button system)(By special specification, up to 5mm(13/64") possibly
Ratio of auxiliary feed to main feed: Gathering: 1:2 (Max. 1:4)
Stretching: 1:0.7 (Max. 1:0.6)
Spring pressure adjusting system
Standard 3.2 mm(l/8")
Byusing gauge sets (throat plate, presserfoot, feed dog,needleclamp)whichconform to the overedging width, possibleto
adjust up to 6.35 mm(l/4")
Max. 7.0 mm(9/32")
DCx27 (Standard), DCxJ27 (For fine synthetic thread) DCxl
24.2 mm(61/64'*)
Slide type (Possible to change the up and down stroke of looper depending on thickness of the sewing cloth)
Built-in inside the machine and geared with the lower looper (MO-816)
Fixed presser foot MO-804, MO-814
Two-stage presser foot... MO-816
Automatic lubrication system by means of gear pump (equipped with oil cooling fan)
-13-
From the library of: Superior Sewing Machine & Supply LLC

nun JUKI INIUSIRIAl GO..ITO.
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Business Office: 23, Kabuki-cho, Shinjuku-ku, Tokyo, Japan
Cable Address: JUKI TOKYO Telex: 22967 JUKITK
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From the library of: Superior Sewing Machine & Supply LLC