Singer 312 U141 User manual

SERVICE
MANUAL
SINGER
Copyright'^ 1977THE SINGER COMPANY
AllRights Reserved Throughout the World
From the library of: Superior Sewing Machine & Supply LLC

H N D E X=
Specifications 2
Parts of the machine head 2
I. Preparation For Installation Of Machine.
1). Placeof installation of machine 3
2). Howto mount the machinehead
•' 3
3). How to mount the motor 3
4). Howto connect the motor to the treadle 3
5). How to mount the bobbin winder assembly 3
6). Howto mount and adjustthe kneelifterand accessories 4
II. Lubrication Before Starting To Sew.
1).Oiltypeandoil reservoirs 6
2). Adjustmentfor lubrication 7
3). Precautionbefore startingto sew 7
III. Preparation For Operation.
1). Selection of thread 8
2), Howto insert the needles 8
3). Methodof threadingthe upper thread 8
4). How to windthe lower thread on the bobbin 9
5). How to adjustthe bobbin winder assembly 9
6). How to placethe bobbininto the hook 10
IV. How To Operate.
1). Start sewing H
2),After sewing 11
V. Stitch Adjustment.
1). Adjustment of stitch length 12
2).
Adjustment of thread tension 12
3).
Adjustment of feed dog height and pressure foot presser 15
4). Proper timing between thehook and needle 16
5),Proper
timing of the hookand take up lever 18
6). Relative positions of thehookandthe opener 18
7).
Positions of feed regulator 18
8). Relative position of feed dog and needles
VI. Qeaning And Lubrication.
1). Cleaning 20
2). Lubrication
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Specifications and Parts of machine head
t SPECIFICATIONS:
Application
Sewing speed
Needles
Needle bar stroke
Thread take up
Feeding system
Stitching length
Presser bar stroke
Hook
Feeding mechanism
Stitching adjustment
Lubrication
Motor recommended
t Parts of machine head
Generalcloth and clothingfabrics,
at 3500 r.pjn.
CAT.No.1901. #14
33.4 mm (1 - 5/16").
Slide type thread take up.
Under feed and needle feed.
O'VS m. m. (0'\/3/16")
7 m.m. (9/32")
Gear driven vertical axisrotatinghook,withopener.
Double eccentric mechanism.
Push button type stitch regulator onarm-top.
Rotating hook Lubrication by pump.
Armshaft, hook shaft and feed drivingmechanism
Automatically lubricated by meansof an oilingdevice
from the oil reservoir in machine arm and bed.
Others Hand oiling.
1/2HP (400W) clutch motor.
@(D (D® @ ®
(SxS)®®® ® (8) (0)
1) Press stud for oil plunger.
2) Press bar for oil plunger.
3) Oil level indicator.
4) Thread guide (top of arm).
5) Arm top cover.
6) Machine pulley.
7) Front cover.
8) Arm.
9) Upper thread tension regulator.
10) Thread controller.
11) Bed.
12) Stitch regulator push button.
13) Slide plate (right).
14) Needle clamp>
15) Slide plate (front).
16) Hook saddle, (right)
17) Throat plate.
18) Hook saddle, (left)
19) Slide plate, (left)
20) Presser foot.
21) Needle bar.
22) Presser bar.
23) Thread guide (lower) .
24) Thread guide (middle)
25) Face plate.
26) Thread guide (upper) .
27) Pre-tension.
28) Feed reverse lever.
29) Thread take-up lever.
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Preparation for installation of machine
. PREPARATION FOR INSTALLATION OF
MACHINE.
1. PLACE OF INSTALLATION OF MA
CHINE.
In order to ensure smooth operation of your
machine at high speed without vibration, the
machine should be set on a level floor.
HOW TO MOUNT MACHINE HEAD
Attach the machine hinges at the rear of the
machine bed and the hinge plates into the table
cutouts with screws provided in accessories.
Place machine so that hooks of hinges fit into
the slots of the hinge plates.
HOWTO MOUNT THE MOTOR
Mount motor to the table in a position that will
locate the drive belt in straight alignment be
tween the machine pulley and motor pulley - as
illustrated. Connect motor to power supply
source with electrical cord extending from the
switch.
HOW TO CONNECT THE MOTOR TO
THE TREADLE.
Pressure on the treadle will be reduced if the
inclination of treadle is not at proper angle.
The best inclination is 30° - 40° as shown in
Fig. (a).
In case of Fig. (b), the treadling gets difficult,
therefore, adjsut the length of the treadle con
necting rod.
HOW TO MOUNT THE BOBBIN
WINDER ASSEMBLY.
Bobbin winder should be mounted in parallel
with belt slot of the table and fixed with 2
screws so that the bobbin winder pulley
touches the belt when the stop latch lever is
pushed forward.
Hinge plate
•C
— Motor pulley
jjfj Machine pulley
30*-40*
Belt slot
Bobbin
winder
f^-ZBobbin winder
/ pulley
Stop latch
lever
Screw
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Preparation for installation of machine
. HOW TO MOUNT AND ADJUST THE
KNEE LIFTER AND ACCESSORIES.
. KNEE LIFTER MECHANISM.
The knee lifter mechanism lifts and lowers the
presser bar. Mount it properly on the table to
promote operating efficiency.
1) Place of Mounting
Mount unit properly on reverse side of table
using screws in accordance with the location
and measurements indicated.
2) How to Mount
Mount knee lifter mechanism in the following
sequence as per illustration.
a) Mount knee lifter bracket on reverse side of
table.
b) Assemble the extension on lifting rod.
c) Assemble knee plate connecting
bar on knee
plate.
d) Mount the knee lifting bar and rod assem
blies on knee lifter bracket.
3) Adjustment
The positioning of lifting rod and extension is
directly related to presser rod up and down
movement and the corresponding action of
pfesser foot. Position the following parts:
a) Lower presser foot to the down position.
b) Loosen and secure screw (B) after adjusting
to
poation (A) for lifting rod and presser
rod as illustrated.
•^28mm^33.5nim
105mm
Knee plate Efki"'"
connecting
Knee plate Extension
Presser rod
Lifting rod
Extension
(BScrew
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c) Loosen screw (C) of knee lifter bracket and
adjust the lifting rod for proper inclination;
tighten screw after adjustment.
4) Placing die Stopper Pin
a) Loosen set screw (D) of stopper pin.
b) Move knee plate to the right so that presser
foot lifts to its highest portion (12.7 mm).
c) Tighten set screw (D).
NOTE
After this adjustment, stopper pin should
contact part (A) of knee lifter bracket.
5) Position of Knee Plate
Adjust knee plate in accordance with the physi
cal
posture of operator to provide for the most
comfortable position then tighten screw (E).
b. OIL PAN
Position oil pan on reverse side of table cut-out
as not to interfere with knee lifter operation,
secure oil pan to table using nails.
c. VIBRATION-PREVENTING RUBBER
The vibration-preventing rubber is used to
stabilize the machine
and thereby to provide
smooth operation. Fit these rubbers at Ae four
comers of the table as shown in the illustration
as follows.
1) Make spot facing of 20 mm radius and 13
mm depth at the four corners of the table.
Be sure to give smooth facing to face A.
2) Nail the vibration-preventing rubbers down
at the four corners of the table as shown in
Fig.
Preparation for installation of machine
Lifting rod
Knee lifter
bracket
5.5%
Extension
® Screw
Knee plate
Vibration
preventing rubber
Nail
Screw
Screw
Stepper pin
13%
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Lubrication before starting to sew
11. LUBRICATION BEFORE STARTING TO
SEW.
1. OIL TYPE AND OIL RESERVOIRS
a. Type of Oil Used.
Use Singer Type A or C oils or equivalent
grades acceptable for industrial sewing
machines.
b. Oil Reservoir located in Arm.
1) To fill the reservoir remove the press
stud for oil plunger.
2) Fill the reservoir to the red mark "H"
of oil level indicator.
c. Oil Reservoir located in Bed.
1) Tilt the machine head backward and
locate the oil filler hole for filling the
reservoir.
2) Fill the reservoir to the red mark "H" of
oil level indicator.
d. Oil Reservoir located In Hook saddles.
1) Remove slide plates to left and right of
throat plate.
2) Remove oil gauges from the left and
right hook saddles.
3) Fill reservoir with oil so that reservoirs
are filled to high mark indicated on oil
gauges.
CAUTION
Check daily to ascertain that oil reservoirs are
filled properly. If oil levels fall below "L" red
mark indications, parts will not be lubricated
and seizing of machine parts will result.
Press stud
Oil level indicator
Oil level indicator Oil filler hole
Oil gauge
Slide plate(left)
Mark
Oil gauge
Slide plate(right)
\
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ADJUSTMENTS FOR LUBRICATION
a. Oil Control Plunger
1) Before starting to operate machine, push
press bar down so that oil penetrates
thoroughly into necessary parts of the
arm.
2) When machine is left idle, release the
press bar by pushing press stud down
ward, to stop automatic lubrication.
b. Adjustment of Hook Lubrication
1) Tilt machine head backward and loosen
the nut on the side of hook saddle to be
adjusted.
2) Turn adjusting screw clockwise to in
crease and counterclockwise to decrease
oil supply.
3) After proper adjustment, tighten the
nut.
PRECAUTIONS BEFORE STARTING
TO SEW
When machine is operated for the first time or
after a long period of idleness, proceed as
follows:
a. Refer to pertinent cleaningand lubrication
procedures.
b.
After reservoirs have been filled to required
levels, depress the press bar for oil plunger.
c. Run machine slowly for approximately 10
minutes so that oil will penetrate thorough
ly into necessary parts.
Lubrication before starting to sew
Press bar for oil
plunger
(before operating)
Press bar for
oil plunger
Press stud
Increase
Adjusting
Nut
(when idle)
Hook Hook
saddle saddle
Adjusting
screw
Nut
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Preparation for operation
III. PREPARATION FOR OPERATION.
1.
2.
8
SELECTION OF THREAD
Always use left-twist thread for upper thread. In
order to check if a thread is right-twist or left-twist,
hold the thread as shown in illustration and twist it
toward you with your right hand thumb and fore-
iinger;
if the twist loosens, the thread is right-twist
and if it tightens, the thread is a left-twist.
HOW TO INSERT THE NEEDLES
(Use.Cat. No. 1901)
a. Rotate the machine pulley toward you so as to
raise the needle bar to its highest position.
b. Ihen loosen the needle clampingscrew.
c. Hold the needles so that the long grooves are
facing inside as illustrated, then insert the
needles as deeply as possible into the needle
clamping holes.
d. Clampneedlessecurelyby tighteningthe needle
clamping screws.
METHOD OF THREADING THE
UPPER THREAD.
The upper thread is passed according to the
following;
a. Raise the thread take up lever to its highest
position and pass the thread in the order of
the numbers ^own in Fig.
b. Threading the thread from the left side spool.
(LI) Threadguide^eft-(top cover)
(L2) Thread retainer (upper hole)
(L2*) Guide pin (right)
(L3) Pre-Tension (upper)
(L3') Guide pin fleft)
(L4) Tension regulator (upper)
(LS) Thread controller disc (back)
(L6) Thread tension ^ring
(8) Thread guide (upper)
(L7) Take up lever hole (upper)
(8) Thread guide (upper)
^) Thread guide (middle)
(10) Thread guide (lower)
(LI1) Thread jguide hole4eft-(needle clamp)
ai2) Needle Ceft)
c. Threadingthe thread from the right side spool
(Rl)
(R2)
(R3)
(R4)
(R5)
(R6)
(8)
(R7)
(8)
(9)
(10)
(Rll)
(R12)
Thread guide-right-(top cover)
Thread retainer (lower hole)
Pre-tension (lower)
Tension regulator (lower)
Thread controller disc (front)
Thread tension spring
Threadguide (upper)
Take up leverhole Oower)
Thread guide (upper)
Thread guide (middle)
Thread guide (lower)
Thread guide hole-rlght-(needle clamp)
Needle (right)
t Pass the thread on (3) pre-tension & (4) tension
regulator between its two discs, and (12) two
needle from in side to out side.
Needle clamping screw
M
Needle clamp
Long—-
groove
faces
(inside)
(L7) (L5) (L3') <L1)
m
"(Rll)
-(R12)
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4. HOW TO WIND THE LOWER THREAD
ON THE BOBBIN.
a. Pass the thread from the spool through
the hole of the thread guide G) as shown
in Fig. next through the tension discs (2).
b. Then wind the thread about 5-6 times on
the bobbin.
c. Fit the bobbin into the bobbin spindle (3)
in such a manner that the thread would be
wound on the bobbin from the underside.
d. Push the lever forward so that the pulley
and the belt will engage.
e. Then the bobbin can be wound with thread
when the machine is rotated.
f. When the bobbin is fully wound with
thread, the pulley will automatically be
free from the belt and stopped.
t This operation can be done while sewing.
5. HOW TO ADJUST THE BOBBIN
WINDER ASSEMBLY.
It is desirable that the bobbin is wound evenly
with thread as shown in Fig. (A). If the thread
is wound unevenly as in (B) & (C), the thread
will not be drawn out smoothly and the thread
tension will tecame irregular.
a. In case of uneven winding:
1) If it is inclined to left as (B), loosen the
screw (A) shown in Fig. and move the
thread guide rest slightly to the right so as
to obtain uniform winding of thread as in
(A).
2) If it is inclined to right as (C), move the
thread guide
rest slightly to the left.
b. Tension of the winding
Particularly in case of nylon thread, there is
fear that the bobbin may be damaged if the
bobbin is wound too tighGy with thread.
Adjust with nut (B) shown in Fig.
c. Winding amount of thread.
Best results are obtained when the bobbin is
wound up to 4/5 of its full capacity with thread
Excessive winding will result in poor draw-k>ut
of the thread;
To adjust the amount of thread wound on the
bobbin, turn the screw (C) shown in Fig. to the
left when the winding is excessive, and to the
right when it is insufficient.
Preparation for operation
Bobbin
Lever
(Adjust by sliding right or left.)
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Preparation for operation
10
HOW TO PLACE THE BOBBIN INTO
THE HOOK.
a) Open the slide plate.
b) Raise the needle bar to its highest position.
c) Open the latch lever (A) shown in Fig.
d) Hold the bobbin and unwind about 5 cm
thread as shown in Fig.
e) Place
the bobbin on the post (B) shown in
Fig.
f)
Then clamp down the latch lever (A)
g) As illustrated
lead the end of thread through the groove
of the hook (1), through the horn (2) and
opener (3), then pull the thread out so that
it is led under the tension spring (C).
Thread
Thread
Thread
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IV. HOW TO OPERATE
1. START SEWING
a. Lift the presser foot.
b. Hold the ends of upper threads with the left
hand and rotate machine pulley slowly so
that needles move down and up.
c. Observe that the bobbin threads will be
picked up by the hooks. Rotate machine
pulley until needles move to their highest
point and observe that the needle threads
are pulling the bobbin threads through the
holes of the throat plate as illustrated.
d. Pull out the bobbin threads and extend
them underneath and to the rear of presser
foot as illustrated. Then close the left and
right slide plates.
e. Place material beneath presser foot to com
mence to sew.
f. Rotate machine pulley so that needles pene
trate the cloth.
g. Then lower presser foot and commence to
sew.
NOTE
Before sewing, leave needle threads pulled
out approximately 10 cm in length so
thread ends are not drawn into machine.
2. AFTER SEWING
a. When sewing is completed, the take up lever
should be at its highest position.
b. Lift the presser foot.
c. Pull out the sewn fabric diagonally to the
left side.
d. lYim both the upper and lower threads.
3. FEED REVERSE STITCH
Reverse sewing can be done during stitching
when the reverse lever is depressed.
How to operate
11
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Stitch adjustment
V. STITCH ADJUSTMENT.
1. ADJUSTMENT OF STITCH LENGTH
Stitch length is adjusted by the stitch regulator
push
button on the bed and the machine pulley
as follows:
a. Depress the push button and rotate machine
pulley slowly toward
you until the push
button goes down further and machine
pulley stops rotation.
b. Press push button further down to permit
further rotation of the machine pulley and
set the desired graduation (0-S) on the
machine pulley to coincide with the mark
on the arm; then release the push button.
WARNING
Do not depress the push button while the
machine is running as this may cause
damage to the machine.
2. ADJUSTMENT OF THREAD TEN
SION
a. Adjust the thread tensions according to the
materials being sewn, the thread used, the
length of stitches and other stitching con
ditions.
1. If the tensions of the needles and bobbin
threads are well balanced, the two
threads will link together in the middle
of the fabric to form perfect lockstitches
(A) as shown in Fig.
2. If either the needle or bobbin thread
tensions are too tight or too loose,
imperfect stitches will result as ^own
in (B) or (C). In (B) the needle thread
tension is too tight and in (C) the ten
sion is too loose.
12
Mark
Machine
Stitch regulating push button Feed reverse lever
o ®
X
X
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b. Tension of Needle Threads
Adjustment of the needle thread tensions is
made by changing the pressure on the
thread tension discs
of the upper thread
tension regulator and the tension and oper
ating range of the thread controller spring
as follows.
1. Pressure of thread tension discs.
The desired thread tension can be ob
tained by adjusting the pressure on the
tension discs by turning the thread ten
sion nut to the right to increase tension
and turning the nut to the left to de
crease tension as shown in Fig.
2. Tension of the thread controller spring.
Adjust the tension of the spring accord
ing to the materials to be sewn as fol
lows.
a. In case of medium weight fabric
adjust ^ring tension to approximate
ly 25 grams.
b. In case
of light fabric and short
stitches adjust spring to 20 grams
tension.
c. In case of heavy fabric and longer
stitches, increase the spring tension
to about 30 grams.
d. Adjust spring tension as follows:
(1) Loosen set screw (A) as shown in
Fig.
(2) Using a screw driver placed in the
slot of the thread controller
stud, turn stud to the left to
increase tension and to the right
to decrease it.
(3)Tighten screw (A) after adjust
ment.
Increase
Stitch adjustment
Increase
Thread tension nut
Thread controller stud
Thread controller spring
13
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Stitch adjustment
14
3. Operating range of thread controller
spring
Change the operating range of thread
controller spring for the fabrics used and
for
adjustment of the take up spring as
follows;
(a) Fabric Used
(1)In the case of light fabrics (small
stitches), increase
the operating
range.
(2) In the case of heavy fabrics (large
stitches), decrease
the operating
range.
(3) In the case of standard fabrics
(standard operating range) adjust
the interval by 8mm - 10mm of
movement of thread controller
spring when the take up lever
moves from its lowest position to
the highest position and applies
tension to the needle thread, as
illustrated.
(b) Thread Controller Adjustment
(1) Loosen the set screw of the
thread controller.
(2) Turn the stopper to the right to
increase the operating range, and
to the left to decrease it.
(3) Securely tighten screw after
making adjustments.
(c) Tension of Bobbin Thread.
There is virtually no need to adjust
the bobbin thread tension except for
special fabrics and thread or loosen
ing
of thread tension screw. As
required, adjust the tension as fol
lows.
(1)Turn the thread tension screw of
the bobbin case to the right to
tighten the tension, and to the
left to loosen the tension.
(2) Check this thread tension screw
periodically to ensure that it has
not loosened during machine
operation. The tension screw is
provided with slots as illustrated
which can be opened to insure
screw will fit more securely.
♦
Standard interval
Thread tension
screw
Increase
Thread controller
discs
Stopper
Loosen
Tighten
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3. ADJUSTMENT OF FEED DOG HEIGHT
AND PRESSER FOOT PRESSURE
a. The height of the feed dog a.sweU as presser
foot pressure is adjusted in accordance with
the following materials used.
(1)For Thin Fabrics. If the feed dog is
raised excessively or the pressure on the
materials to be sewn is too heavy, puck*
ered sewing of material will result.
(2) For Heavy Fabrics. If the feed dog is
not raised sufficiently or the pressure on
the materials to be sewn is too light,
feeding of material will be poor and
stitches will become uneven or skipping
may result.
(3) Feed DogHeigfit
The height
of feed dog is measured when
the feed dog is raised to its highest
position (by rotation of machine pulley)
above the throat plate.
Ihin Fabrics Approx. 0.8mm
above throat plate
Standard Fabrics ... .Approx. 1.0mm
above throat plate
Heavy Fabrics Approx. 1.2mm
above throat plate
b. Adjustment of Feed Dog Height
1) Tilt machine head backward.
2) Rotate machine pulley until feed dog is
raised to its highest position above
throat plate.
3) Loosen feed bar screw.
4) Adjust feed dog to desired height by
moving feed bar up or down, then
tighten feed bar screw.
c.
Adjustment of Presser Foot Pressure
1) Turn presser regulating screw (A)
Oocated in center of arm illustrated)
clockwise to increase pressure.
2) Turn screw (A) counterclockwise to de
crease pressure.
Stitch adjustment
>w]^j7f7i7fm7>nn7)7iu?fn.
0.8""
m
l.Oao
mr,
1.2aa
zzzr:
Feed bar
Screw
Increase
Decrease
==izu
15
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Stitch adjustment
4. PROPER TIMING BETWEEN HOOK
AND NEEDLE
When thiead gets entangled on the hooks or
position of hooks is changed due to strain or
other causes, it may be necessary to remove,
replace or reposition the hook with respect to
the needle position.
16
a. Remove hook as follows:
1) Rotate machine pulley until needle is
raised to its highest position.
2) Tilt machine head backward.
3) Loosen three screws on hook gear
(small) shown in illustration.
4) Set machine head upright and move slide
plate to remove underbed components.
5) In sequence, remove throat plate, feed
dog,
opener and hooks.
b. Replace hook as follows:
1)
Replacement of hook and associated
components is the reverse of removal
procedure described (in step a.5).
2) Replace throat plate by aligning the
hook finger of throat plate with the pro
tuberance of hook, as illustrated.
c. Ralative position of hooks and needles for
proper timing.
1) Set amount of stitch length with gradua
tion (3) of dial on machine pulley.
2) Raise needle 2.5mm from its lowest
position and adjust position of hook and
needle in accordance with illustration as
follows:
Hp (Point) of hook Center of the
needle.
Top of needle eye 1.6mm below
the tip (point)
of hook.
The gap between the lateral face of
needle and point of hook
0.05mm
Hook Opener
Hook
Hook gear(smal])
Screw
Hook saddle
Slide
plate
Hook finger Protuberance
of hook .txy
of needle ♦
Lowest position"y
of needle
2.5%raise
Center of
needle' Va ^
0.05%
(The side)
Tip of hook (The surface)
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d. Adjust point of hook to centerline of needle
as follows:
1) Hit machine head to reai and loosen the
3 set screws on hook gear (small) as
illustrated.
2) Set machine head upright and rotate
machine pulley until needle has been
raised 2.Smm from its lowest position.
3) Turn the hook by hand and align the
point of hook to needle center.
4) Tighten the set screws loosened in step
1.
e. Adjust gap between lateral face of needle
and point of hook to measure 0.05mm as
follows:
1) Tilt machine head to rear and loosen
hook saddle screws A & B, as illustrated.
2) Loosen set screws C, illustrated.
3) Move hook saddles to right or left to
adjust gap of needle to point of hook
to 0.05mm, tighten all screws loosened
in steps 1 and 2.
Adjust needle position as follows:
1)
Remove face plate.
2) Loosen screw of needle bar holder,
adjust needle height then tighten screw.
Hook saddle
Stitch adjustment
Hook
Hook gear
(small)
Screw
Hook saddle
'Needle bar
'Needle bar holder
Screw
17
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Stich adjustment
5. PROPER TIMING
TAKE-UP LEVER
OF HOOK AND
When removing or replacing the timing belt,
the timing of the hooks and take up lever must
be adjusted as follows.
1)
Remove needles to avoid damaging them.
2) Rotate machine pulley until take-up lever is
at its highest point.
3) Tilt machine head to the rear and check
whether arrow (timing marks) of timing belt
pulley and the boss of driving shaft bushing
holder are in line.
4) If not in line, slide belt off (lower) pulley
and rotate pulley so that its timing mark is
in line with boss of driving shaft bushing
holder.
5) Replace belt on pulley.
6. RELATIVE POSITIONS OF HOOK
AND OPENER
a. Rotate machine pulley until opener holder
is at its further most position from throat
plate.
b. Check the gap between hook and opener. It
should measure approximately 0.2mm as
illustrated.
c. If not, adjust the position of opener, after
loosening screw B, to obtain an approximate
gap of 0.2mm. Tighten screw after adjust
ment.
7. POSITION OF FEED REGULATOR
(Stitch length regulator on the bed)
a. Refer to page 12, adjustment of stitch
length; press stitch regulator push button
and rotate machine pulley counterclockwise
until it stops. This is the longest stitch
length and should show graduation (S) of
machine pulley in line with marking on the
arm.
b. Rotate machine pulley clockwise and stitch
length should be (0) and in line with mark
ing on arm.
c. If the (0) or (S) graduations do not cor
respond with the mark on arm, adjust the
feed regulator as follows:
18
Abt. 0.2mm
Opener
Boss of driving shaft
bushing holder
Timing belt
Timing mark
Timing belt pulley
Opener holder
From the library of: Superior Sewing Machine & Supply LLC

1) Tilt machine head to the rear.
2) Loosen the two largei screws of feed
regulator driving link.
3) Set machine head upright. With push
button depressed, repeat steps 7a and 7b
and align the (0) and (5) graduations
with the mark on the arm. Release the
push button.
4) Repeat step 1 and tighten the screws
loosened in step 2.
RELATIVE POSITION OF FEED DOG
AND NEEDLES'
The feed dog should be set so that when the
needles ate down they will be in the center of
the needle holes. If not, proceed as follows:
a. Push the stitch regulator push
button on the
bed; rotate machine pulley and align gradu
ation (0) to the mark on the arm.
b. Hit machine head to rear.
c. Loosen screw (A) and (B) of feed connect
ing cranks as illustrated.
d. Set machine head upright and adjust feed
bar forward or backward so that the needles
are positioned in the center of the needle
holes.
e. Repeat step b. and tighten the loosened
screws (A) and (B) of step c.
f. Check whether the center line of the link
and the feed connecting crank (right) is at
a right angle to the center of the feed con
necting shaft.
g. If not, remove front cover and loosen screw
(C): adjust needle bar connecting crank by
moving the link toward the arrow so as to
assure a right angle configuration of the
parts.
h. After adjustment tighten screws (A), (B),
and (C).
Screw®
Front cover
ScrewQ
Needle bar
connecting crank
Feed
connecting
crank
(right)
Stitch adjustment
Feed regulator
Driving jink
Feed connecting crank
Screw®
Feed connecting
crank
(right)
Screw®
19
From the library of: Superior Sewing Machine & Supply LLC