Singer 281-1 User manual

Form 21288
(264)
K
SINGER
Service Manual
Machines
281-1, 281-3 and 281-21
Regulation View —Mochine 281-1
THE SINGER COMPANY
Copyright © 1964 by The Singer Company
Copyright Under International Copyright Union
All Rights Reserved under Inter-Amerlcon Copyright Union
*A Trodetnork of THE SINCER COMPANY
Printed In U. S. A.
From the library of: Superior Sewing Machine & Supply LLC

CONTENTS
DESCRIPTION 3
INSTALLATION 4
LUBRICATION AND CLEANING 4, 5
OPERATION 4, 9
ADJUSTMENT 10, 16
PARTS Rear of Manual
INDEX
Bobbin, Removal and Replacement 8
Bobbin Case, Removal and Replacement 8
Bobbin Case, Threading 8
Bobbin Cose Holder, Removol and Replacement 13
Centralizing the Feed Dog 15, 16
Check Spring, Height Setting,... 14
Check Spring, Tension Adjustment 14
Check Spring, Timing 14
Cleaning 6, 13
Description of Machines 3
Determining Thread Twist 7
Disc Tension 3
Federal Stitch Type 3
Feed Bar Eccentric Hinge Pin 14, 15
Feed Bar Linkage 16
Feed Dog, Centralizing 15, 16
Feed Dog, Height Settings 14, 15
Feed Eccentric Stop Screws Available 15
Feed Leveling 15
Feed, Pendant Link 3
Filter (Sewing Hook Lubrication) 5
Guard, Needle. 13
Guard, Needle Thread 3
Guide Bracket 16
Hook (see Sewing Hook)
Hook Section 13
Installation 4
Knee Lifter 3, 4
Length of Stitch 3, 9, 10
Leveling the Feed IS
Lifting Bracket 16
Lint Wiper 3
Lower Threading 8
Lubricating System 3-5
Lubricotion 4, 5
Machine Base 4
Machine Pulley ^
Magnet on Oil Pump 6
Materials Sewn 3
Maximum Stitch Length 3, 15
Needle Bar Bushing (Lower), Setting 10
Needle Bar Height, Setting 10
Needle Bar Stroke 3
Needle Clearance with Hook, Setting 11. 12
Needle Guard at Loop-taking Time.. 13
Needle Guard, Stringing 13
TO ALL WHOM IT MAY CONCERN:
Needle Recommended .......6
Needle, Setting 6, 7
Needle Stop 10
Needle Thread Guard 3
Needle Threading 7
Oil Flow Regulator 5
Oil Flow Window. 3, 5
Oil Pump 3, 6
Oil Recommendations 5
Oil Reservoir 3, 4
Oil Retaining Collor 11
Oil Spray
Pattern 5
Parts Charts Rear of Manual
Pendont Link Feed 3
Presser Bar Height, Setting 16
Presser Bar Lift.. 3, 16
Presser Foot Clearance 16
Presser Foot Pressure, Adjustment 9
Preventing Unauthorized Changes in Stitch Length 10
Position Finger, Settings 12
Radial Position of Sewing Hook 11
Regulator Button (Stitch Length) 9, 10
Reservoir 3, 4
Sewing Hook Clearance with Needle, Setting 11, 12
Sewing Hook Filter Screw 5
Sewing Hook
Lubrication 5
Sewing Hook, Oiling Wick 5
Sewing Hook, Timing 11
Space at Right of Needle 3
Speed Recommendotions 6
Stitch Length, Maximum 3, 15
Stitch Length, Preventing Unauthorized Changes 10
Stitch Length, Regulation 9, 10
Stop Screws (Feed Eccentric) 16
Stringing the Needle Guard 12
Take-up Lever Movement 14
Tension of Check Spring, Adjustment 14
Thread 7
Threoding, Lower 8
Threading, Upper 7
Thread Tensions.... 9
Timing 11,14
Thread Twist, Determination 7
Upper Threading .7
Unauthorized Changes in Stitch Length, Preventing 10
V-belt 3
Wick, Sewing Hook 5
The improper placing or renewal of the Trodemork SINGER* or any other of the Trodemorks of The Singer Company
(all of which ore duly
Registered Trademarks) on any machine that has been repaired, rebuilt, reconditioned, or altered
in ony way whatsoever outside aSINGER factory or on authorized SINGER agency is forbidden.
From the library of: Superior Sewing Machine & Supply LLC

DESCRIPTION OF MACHINES
Machines 281-1, 281-3 and 281-21 are high speed,
single needle, lockstitch machines designed for sewing
a wide variety of fabrics ranging from light weight to
heavy weight.
Outstanding
straight line stitching is produced by
these machines in materials such as wash-and-wear,
synthetic and natural fabrics.
General Features
Balanced, air cooled, rotating hook. Horizontal
axis.
Lint wiper keeps lint and abrasive matter from ac
cumulating on hook.
Drop feed consisting of pendant link feed with feed
leveling hinge pin.
Pendant link feed mechanism maintains longer feed
ing cycle.
Three plain superfinished bearings support the
arm shaft.
Fully automatic lubricating system with oil flow
window in direct view of operator.
Knee lifter mechanism integral with machine
base
and oiI reservoir.
independent light fixture mount.
Federal stitch type 301.
Improved
needle thread guard and other thread hand
ling parts. Disc
tension.
Machinepulley 147139 for 3/8 inch V-belt.
Variations of Machine Varieties
Machine 281-1
Light weight to medium-heavy weight fabrics.
Needle bar stroke, 1-13/64 inches.
Presserbor lift, 5/16 inch.
Maximum
stitch length: Feed eccentric stop screw,
regularly furnished, limits the maximum stitch length
to 7
stitches per inch. A stop screw for 5-1/2
stitches per inch will be furnished when specified
on order.
Space at right of needle, 11 inches.
Machine 281-3
Light weight to extra-heavy weight fabrics.
Needle bar stroke, 1-7/16 inches.
Presser bar lift: Regularly furnished with 3/8 inch
lift for sewing light weight to heavy weight fabrics.
Available on order with 7/16 inch lift for sewing
extra-heavy weight fabrics.
Maximum stitch length, 5-1/2 stitches per inch.
Space at right of needle, 11 inches.
Machine 281-21
Light weight to medium-heavy weight fabrics.
Needle bar stroke, 1-13/64 inches.
Presser bar lift, 9/32 inch.
Maximum stitch length: Feed eccentric stop screw,
regularly furnished, limits the maximum stitch length
to 7 stitches per inch. A stop screw for 5-1/2
stitches per inch will be furnished when specified
on order.
Space at right of needle, 8inches.
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INSTALLATION
GASKET
PLUNGER
HIGH MARK
OIL
RESERVOIR
LOW MARK
Fig. 2. Machine Base and Oil Reservoir
See that plunger is in place, as shown in Fig. 2, Use shims on corners, when required to insure that
before placing machine on base, base is level, so that oil level will be accurately in
dicated by marks on bose.
Machine base and oil reservoir fits into standard
table cut-out and rests on four corners without bolting. Machine head is not fastened but should rest on cork
Rasp edges of cut-out, shown in Fig. 2, if necessary, gasket in base. Machine hinge pins must not support
so that machine does not touch table when placed on the head except when machine is tilted back,
base.
STOP SCREW LOCK NUT ROCK SHAFT
CLAMP SCREWS
LIFTER LEVER
REAR STOP DOG
KNEE PLATE
Fig. 3, Knee Lifter
THEKNEE LIFTER
Knee lifter is shipped assembled to the base ex
cept for the knee plate and lifter lever.
Loosen the two clamp screws shown in Fig. 3 and
slide the rock shaft forward to position shown. Attach,
lifter lever.
Set the stop screw, Fig. 3, so that there is only a
little play in the lever before it starts to lift the presser
bar. Then tighten lock nut on stop screw.
Set the rear stop dog to allow the presser bar to be
raised to its limit and tighten the two clamp screws.
CAUTION: Do not operate machine until it has been
thoroughly lubricated in accordance with the following
instructions.
From the library of: Superior Sewing Machine & Supply LLC

LUBRICATION
Before starting machine, the oil reservoir must be
filled to
HIGH MARK shown in Fig. 2
Use SINGER OIL "TYPE A" or "TYPE C", Use
"TYPE C" OIL when an oil is desired which will
produce a minimum of stain on fabrics even after a
long period of storage.
Do not use additives in sewing machine oil, as
they may cause a reduction in normal oil flow that
can result in damage to machine.
Should the oil flow, passing through the oil flow
window as shown in Fig. 4, stop or become erratic,
STOP MACHINE AND DO NOT RUN AGAIN until the
cause has been eliminated.
Check oil level often to keep it from going below
low mark.
The Oil Flow Regulator
Lubrication of the sewing hook is automatically
controlled by the oil flow regulator shown in Fig. 5.
Regulator is set at the factory for lubrication under
average sewing conditions.
To determine whether oil is properly flowing to the
hook, run machine for approximately one minute to es
tablish a uniform rote of flow. Then open the bed slide,
hold a piece of paper under the hook and run the ma
chine for about ten seconds. There should be a distinct
line of oil on paper, beneath the hook bearing, with a
fine spray on each side of this line.
If there is no trace of oil or an excess of oil on the
paper, turn oil flow regulator to right or left to increase
or decrease the flow of oil, as shown in Fig. 5.
Machine must run at least one minute between ad
justments to insure uniform oil flow.
If
the proper rote of flow cannot be obtained by
turning the regulator inspect the oil flow mechanism
as follows:
Remove needle, bobbin and bobbin case from ma
chine.
Remove bracket screw and position finger shown in
Fig. 5.
Loosen two hook body screws and turn machine
pulley until feed bar
reaches its highest point.
SHOULD SHOW STEADY FLOW OF OIL
Fig. 4. Oil Flow Window
THREAD GUARD HOOK BODY SCREWS
FEED BAR
POSITION FINGER
tT
BRACKET SCREW OIL FLOW REGULATOR
Fig. 5. Oil Flow Regulotor
SEWING HOOK
OIL FLOW REGULATOR
ojA
14
3.
/ / 'f/V
FILTER SCREW WICK
Fig. 6. Sewing Hook Filter Screw and Wick
Turn the sewing hook until thread guard is at the
bottom as shown in Fig. 5 and slide hook
from shaft.
Loosen filter screw shown in Fig. 6 and check to
see if wick has become detached or clogged.
Inspect all passages for dirt and lint accumulation.
Replace wick if necessary.
Assemble sewing hook and position finger to ma
chine.
Re-check oil flow as previously instructed.
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CLEANING
Using a short bristle brush (not point of scissors or
Tilt machine back on hinges. Wrap clean rag around
other sharp instrument), remove lint and other waste magnet, shown in Fig. 7, on oil pump body and pul
from around sewing hook, from between feed rows and accumulated foreign particles from magnet.
underside of throat plate and from all other operating
points.
CLEAN
Wipe exterior of machine dry with a soft cloth.
MAGNET
Fig. 7. Magnet on Oil Pump Body
SPEED
Maximum speed for machine 281-1 and 281-21 is
6000 stitches per minute.
Maximum speed for Machine 281-3 is 5000 stitches
per minute.
It is advisable to operate new machines at a speed
of 500 stitches less than maximum, for the first 100
hours of
operation.
NEEDLES
Machines 281-1 and 281-3
Use SINGER* Needle, Catalog 1955, in sizes rang
ing from 8 to 22.
Machine 281-21
Use SINGER* Needle Catalog 1361, in sizes rang
ing from 8 to 22.
Size of needle to be used should be determined by
weight of thread and type of material being sewn.
Orders for
needles should specify quantity required,
size number and catalog number.
For example:
100 No. 16, Catalog 1361 Needles
SETTING THE NEEDLE
Turn machine pulley over toward operator until
needle bar reaches highest point as shown in Fig. 8.
Loosen needle clamping screw. Insert needle into
needle bar as far as it will go, with long groove of
needle to the left and eye of needle directly in line
with arm of
machine. Then tighten the clamping screw.
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THREAD
Left twist thread should be used in needle.
Either right or left twist thread may be used in
bobbin.
Thread twist is determined by holding thread as
shown in Fig. 9 and twirling thread over toward you.
If left twist, strands will wind tighter. If right twist,
strands will unwind or separate.
Rough or uneven thread, or thread which passes
through needle eye with difficulty, will interfere with
successful operation of the machine.
UPPER THREADING
Turn machine pulley over toward operator until
needle bor is at highest point.
Pass thread through threading points indicated in
Fig. 10. Draw approximately two inches of thread
through
needle eye with which to start sewing.
1.
MOVE TO
HIGHEST POINT
LONG GROOVE
2.
LOOSEN
CLAMPING SCREW
INSERT NEEDLE UP
AS FAR AS POSSIBLE
Fig. 8. Setting the Needle
HOLD THIS END
TWIRL OVER
TOWARD YOU
Fig. 9. Determining Thread Twist
Fig. 10. Upper Threading
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1. OPEN LATCH
2. HOLD LATCH
AND PULL
CASE FROM
HOOK
LOWER THREADING
Bobbin Removal
Turn machine pulley over toward operator until
needle bar is at highest point.
Reach beneath bed of machine with left hand and
remove bobbin cose from machine as shown in Fig. 11.
Release latch and bobbin will drop out of case, as
shown in Fig. 12.
Threading Bobbin Case
Fig. 11. Removing Bobbin Cose
Hold bobbin so that thread will unwind in the direc
tion shown in Fig. 13. Hold bobbin case as shown and
place bobbin into it.
Pull thread into slot and under tension spring,
shown in Fig. 14, so that thread enters delivery eye
at end of spring.
Bobbin Case Replacement
Place bobbin case on center stud of bobbin case
holder and release latch. Place bobbin case back until
latch catches near end of stud as shown in Fig. 15.
Draw about two inches of thread from bobbin to start
the sewing.
3. RELEASE LATCH
4. BOBBIN DROPS OUT
Fig. 12. Removing Bobbin
SLOT NEAR TOP
c
Fig. 13. Replacing Wound Bobbin
1. HOLDING LATCH, REPLACE
BOBBIN CASE ON STUD
1. PULL THREAD
INTO SLOT
2. DRAW THREAD
DOWN AND
UNDER SPRING
DELIVERY EYE
3. TURN BOBBIN
CASE OVER.
DRAW THREAD
UP AND INTO
DELIVERY EYE
Fig. 14. Threading Bobbin Case
2. RELEASE LATCH.
Fig. 15. Replacing Bobbin Case
3. PRESS BACK, UNTIL LATCH
CATCHES GROOVE IN STUD.
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I ADJUSTING THE TENSION
Tension on thread should be as light as possible
while still sufficient to set stitches correctly in mate
rial.
Regulate needle thread tension, as instructed in
Fig. 16. Make certain presser foot is
DOWN during
tension adjustment.
Tighten lock nut to maintain
tension adjustment.
Regulate bobbin thread tension as instructed in
Fig. 17.
ADJUSTING THE PRESSURE
Correct presser foot pressure helps insure proper
feeding of material.
Pressure should be as light as possible while still
sufficient to insure correct feeding of material.
Regulate as instructed in Fig. 18 with presser foot
down.
Pressure regulating thumb screw is fitted with
lock nut.
Tighten lock nut to maintain pressure adjustment.
REGULATING THE STITCH LENGTH
Changes in stitch length should never be attempted
while the machine is running.
See page 3 for information on maximum stitch length
for your machine.
Regulate the stitch length, as instructed in Fig. 19.
Button mentioned in Step 4, Fig. 19, drops into
notch with an audible click.
MORE TENSION
2. TURN
THUMB NUT
1, LOOSEN
LOCK NUT
LESS TENSION
Fig. 16. Needle Thread Tension
TURN
REGULATING
SCREW
MORE PRESSURE
1. LOOSEN
LOCK NUT
9
MORE TENSION ^ LESS TENSION
Fig. 17. Bobbin Thread Tension
-2. TURN
THUMB SCREW
LESS PRESSURE
Fig. 18. Presser Foot Pressure
1. STOP MACHINE 3. TURN MACHINE PULLEY
2. DEPRESS BUTTON TOWARD YOU SLOWLY
T
4. UNTIL BUTTON
5. THEN TURN MACHINE
PULLEY TO DESIRED
STITCH LENGTH AND
DROPS INTO NOTCH RELEASE BUTTON
Fig. 19. Regulating the Stitch Length
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BUTTON
RETAINING
RING
ARM TOP
I I .COVER
Fig. 20. Removing Stitch Length Regulator Button
10
BUSHING
SET SCREW
THROAT PLATE
SEAT
BOTTOM OF
LOWER NEEDLE
BAR BUSHING
2.312" (281-1, 281-21)
2.599" (281-3)
Fig. 21. Correct Setting: Needle Bar. Bushing
CLAMPING
SCREW
THROAT PLATE
SEAT
(2) " ©
UPPER
TIMING
MARK
NEEDLE STOP
1.031" (281-1, 281-3)
0.866" (281-21)
Fig. 22. Correct Height: Needle Bar
PREVENTING UNAUTHORIZED
CHANGES IN STITCH LENGTH
Stitch regulator button may be removed by loosening
the tour screws and removing arm top cover, shown in
Fig. 20.
Remove retaining ring near tip of button allowing
button to be withdrawn.
Hole in top cover should then be filled by inserting
plug screw 140607 which may be obtained at additional
charge.
Replace arm top cover.
Inspect and adjust the machine, when it is required,
in the order given.
SETTING THE LOWER NEEDLE BAR |
BUSHING I
Gauge distance from throat plate seat to bottom of
lower needle bar bushing, as shown in Fig. 21, is - - -
2.312 inches for Machines 281-1 and 281-21.
2.599 inches for Machine 281-3.
Raise or lower needle bar bushing, as required to
obtain correct height setting, after loosening bushing
set screw shown in Fig. 21.
SETTING THE NEEDLE BAR HEIGHT f
Remove face plate, slide plate and throat plate.
When needle bar is at its lowest point (during rota
tion of machine pulley), the gauge
distance from throat
plate seat to needle stop in needle bar, as shown in
Fig. 22, is - - -
1.031 inches for Machines 281-1 and 281-3.
0.866 inch for Machine 281-21.
When needle bar is set at correct height, UPPER
TIMING MARK on needle bar will be level with bot--
tom of lower needle bar bushing.
To set needle bar height, remove face plate, slide
plate and throat plate from machine. Loosen needle bar
clamping screw shown in Fig. 22.
Raise or lower
needle bar as may be required. Securely tighten clamp
ing screw. Replace all other parts previously removed.
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TIMING THE MACHINE
Timing the machine consists of first adjusting the
radial position of sewing hook with relation to move
ment of
needle bar and needle thread take-up lever, to
make certain that loop of thread formed by needle will
be correctly taken by point of hook at proper time.
The check spring and feed
are then timed to syn
chronize their motions with needle and hook movement.
TIMING THE SEWING HOOK
Remove slide plate, throat plate, presser foot and
feed dog.
Turn machine pulley over toward operator until
needle bar reaches its lowest point and rises to posi
tion where LOWER TIMING MARK on needle bar is
level with bottom of lower needle bar bushing, as shown
in Fig. 23.
At
this position, point of sewing hook should be at
center of needle, as shown in inset, in Fig. 23.
Loosen two hook body screws shown and turn hook
on shaft as required to bring point of hook to center of
needle. See Fig. 24.
Make certain that hub of hook is against oil re
taining collar and tighten hook body screws.
Check clearance between needle and hook point,
in accordance with the following instructions.
SETTING THE CLEARANCE BETWEEN
NEEDLE AND HOOK POINT
Check to see that needle is properly seated in
needle bar and time sewing hook as previously in
structed.
Point of sewing hook should pass needle as closely
as possible without striking or deflecting needle.
A clearance of about the thickness of a piece of note
paper (approximately .005 inch), as shown in Fig. 25,
is sufficient.
EYE
HOOK
POINT
CLEARANCE
ABOVE EYE
HOOK POINT AT
CENTER OF
NEEDLE
LOWER TIMING
MARK LEVEL
WITH BOTTOM
OF LOWER
^ NEEDLE BAR
BUSHING
Fig. 23. Hook Point at Center of Needle
HOOK
BODY
SCREWS
Fig. 24. Hook Body Screws
OIL
RETAINING
COLLAR
NOTE-PAPER
FLAT OF
HOOK POINT
Fig. 25. Clearance Between Needle and Hook
11
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SETTING THE CLEARANCE BETWEEN
NEEDLE AND HOOK POINT (Continued)
To move hook point toward or away from needle,
first remove slide plate, throat plate and bobbin case.
Then, loosen the two bevel gear screws shown in Fig.
26 and loosen bushing set screw shown in Fig. 27.
MAKE CERTAIN THAT BEVEL GEARS ARE
KEPT IN MESH CONSTANTLY UNTIL THEIR SCREWS
ARE SECURELY RETIGHTENED.
HOOK
SHAFT
BEVEL
GEAR BEVEL
GEAR
SCREWS
ALWAYS
KEEP ^ ^
GEARS
IN MESH
Fig. 26. Bevel Geor Screws
LOOSEN
BUSHING
SET SCREW
1/4" BRASS
DRIFT PIN
TAP VERY
LIGHTLY
TOWARD
NEEDLE.
DO NOT DAMAGE
12
Fig. 27. Position of Drift Pin when
Moving Hook
Toward Needle
BOBBIN
CASE
HOLDER
POSITION
FINGER
1
.018" TO .022"
CLEARANCE
POSITION
FINGER
SCREW
Fig. 29. Position Finger
Using a light mallet and a 1/4 inch brass drift pin,
move hook assembly toward or away from needle as
required. Figs. 27 and 28 show correct placement of
drift pin. TAP VERY LIGHTLY to avoid damaging
hook assembly.
Securely tighten bushing set screw.
Remove all end play from hook shaft by moving
hook assembly firmly against front hook shaft bushing
and, at the some time,
moving hook shaft'bevel gear
toward sewing hook end of shaft.
Tighten screw 1, Fig. 26, on bevel gear. Securely
tighten bevel gear screw 2, Fig. 26.
Replace all parts previously removed.
Check thread clearance between position finger
and bobbin case, as instructed next.
TAP VERY
LIGHTLY
AWAY QZ
FROM NEEDLE
1/4" BRASS
DRIFT PIN
LOOSEN
BUSHING
SET SCREW
DO NOT
HIT
BRIDGE
Fig. 28. Position of Drift Pin when
Moving Hook Away from Needle
SETTING THE POSITION FINGER
Clearance between position finger and bobbin case
holder should be just sufficient to allow thread to pass
through easily. Normally an .018 to .022 inch clear
ance, as shown in Fig. 29, is required. If necessary,
bend position finger CAREFULLY to achieve this
setting.
Top surface of the position finger must be kept
level with the top surface of the bobbin case holder.
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BOBBIN-
CASE
HOLDER
STRINGING THE NEEDLE GUARD
HOOK POINT
-NEEDLE GUARD
Correct
Relationship
LARGE
NEEDLE
BOBBIN
CASE
HOLDER
Incorrect:
Stringing Required
HOOK
POINT
NEEDLE
GUARD
BOBBIN
Fig. 30. Needle Guard at Loop-Taking Time
POSITION
FINGER
SLOT
POSITION
FINGER
FEED BAR
HOOK POINT
NEEDLE GUARD
Incorrect
Too Much Metal
Removed from Guard
3 SMALL
SCREWS
The needle guard on the bobbin cose holder, shown
in Figs. 30 and 33, should prevent needle from con
tacting hook or bobbin cose at any time. See Fig. 30
(A) for correct relationship. When large needles (size
20 or larger) are used, needle guard may deflect needle
too for toward left resulting in damage to needle. See
Fig. 30 (B). To avoid this, it may be necessary to
string the needle guard in accordance with the follow
ing instructions.
Remove needle, slide plate, throat plate and bobbin
cose from machine.
Turn machine pulley until feed bar, Fig. 31, is at
its highest point.
Remove position finger shown in Figs. 29 and 31.
Turn hook body to position shown in Fig. 31 and
remove three small screws and hook section shown.
Turn bobbin cose holder until position finger slot
on thread guard is at location shown in Fig. 32. Slip
bobbin case holder out of hook body.
Remove a slight amount of metal from needle guard
by rubbing needle guard along a 1/8 inch strip of very
fine emery cloth,
as shown in Fig. 33.
EXTREME CARE should be taken to avoid removal
of too much metal as this may permit needle to strike
hook. See Fig. 30 (C). Bobbin case holder will then
need replacement.
Clean bobbin case holder thoroughly before re
placing it in hook body.
Replace all ports in reverse order instructed for
removal.
HOOK POINT
1^ ' HOOK SECTION
Fig. 31. Hook Section
HOOK BODY
POSITION FINGER
SLOT ON THREAD
GUARD
BOBBIN CASE
HOLDER
Fig. 32. Bobbin Cose Holder
GUARD
l/8"#320 EMERY
Fig. 33. Stringing Needle Guard
13
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SETTING THE CHECK SPRING HEIGHT
Thread the machine. Turn machine pulley over
slowly toward operator, observing check spring shown
in Fig. 34.
When take-up lever begins to rise, check spring
should make a slight dip and return to its higher posi
tion.
As take-up lever approaches top of its stroke, set
ting the stitch, check spring should be drawn all the
way down.
CHECK SPRING
HIGHER
Dtp
STUD
i; LOWER
Fig. 34. Check Spring
STUD
SET SCREW
1/32" FOR "WASH AND WEAR"
1 MATERIAL
FEED DOG TEETH
PARALLEL TO
THROAT PLATE
if
THROAT
3/64" FOR ALL OTHER MATERIALS PLATE
Fig. 35. Correct Height of Feed Dog
HINGE PIN ECCENTRIC
HINGE PIN ECCENTRIC
14
FLAT
SET FOR 3/64" RISE SET FOR 1/32" RISE
Pig. 36. Feed Bar Hinge Pin (Eccentric)
As take-up lever descends, check spring should
return to rest.
To increase or decrease height of check spring
(which respectively increases or decreases its move
ment), loosen stud set screw shown in Fig. 34. Turn
stud along with entire check spring assembly to set
check spring height as required. Securely tighten set
screw.
NOTE: Height setting should be checked each time a
different presser foot is used with machine.
SETTING THE CHECK SPRING TENSION
Tension on check spring should be sufficient to
insure action at top speed but light enough to allow
check spring to be drawn all the way down.
To adjust, first make certain that stud set screw
shown in Fig. 34 is securely tightened. Then, using a
screwdriver in slot of stud, turn stud alone toward left
to decrease tension or toward right to increase tension.
SETTING THE FEED DOG HEIGHT
Feed dog height should be adjusted with machine
set for longest stitch. ALL the teeth of the feed dog
should rise equally high above the throat plate, as
shown in Fig. 35.
The correct height of feed dog for wash and wear
fabrics is 1/32 inch above throat plate.
For all other fabrics the correct height is 3/64 inch
above throat plate.
To set feed dog at correct height, loosen the two
hex-head screws shown in Fig. 37.
To obtain a height of 3/64 inch above throat plate,
turn hinge pin eccentric, Fig. 36, until flat on slotted
end is at top as shown.
To obtain a height of 1/32 inch above throat plate,
turn hinge pin eccentric until flat is at bottom.
To
raise or lower the REAR END of feed dog, turn
hinge pin
eccentric out of set position, as required.
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SETTING THE FEED DOG HEIGHT (Continued)
If desired height cannot be obtained as previously
stated, loosen clamp screw on crank shown in Fig. 37.
Raise or lower feed bar as required to obtain desired
height. Securely tighten clamp screw.
Level the feed dog by means of hinge pin eccentric
as previously instructed. Securely tighten the two hex~
head
screws shown in Fig.. 37.
NOTE: Variations in feed dog height may sometimes
be necessary to balance height in relation to
presser foot pressure.
AVAILABLE FEED ECCENTRIC STOP SCREWS
Machine is prevented from making longer stitches
than a predetermined maximum by a stop screw shown
in Fig. 38, in
the feed eccentric.
The following stop screws are available for these
machines:
140256, 7 stitches per inch
140257, 5)4 stitches per inch
140258, 14 stitches per inch
140568, 8 stitches per inch
CENTRALIZING THE FEED DOG
Feed dog should never contact edges of throat plate
but should move midway between sides of throat plate
slots and maintain its movement equidistant from'front
and rear
edges of throat plate slots.
Sidewi se Setting
To move feed dog toward left or right, loosen
the
two clamp screws on feed bar carrier and the clamp
screw on feed bar crank, shown in Fig. 39.
Move feed bar as required to position feed dog mid
way between sides of throat plate slots..
Make certain that feed dog height is correct as in
structed previously.
Securely tighten all three clamp
screws.
CRANK
FEED BAR
HINGE PIN
ECCENTRIC
CLAMP SCREW
HEX-HEAD
SCREWS
Fig. 37. Feed Bar and Crank
FEED ECCENTRIC
STOP SCREW
Fig. 38. Feed Eccentric Stop Screw
CLAMP SCREW
FEED BAR CRANK
FEED BAR^ U)
TWO CLAMP SCREWS FEED BAR CARRIER
Fig. 39. Centralizing the Feed Dog
15
From the library of: Superior Sewing Machine & Supply LLC

CENTRALIZING THE FEED DOG (Continued)
Lengthwi se Setting
Set machine for longest stitch and loosen hex-head
screw, shown in Fig. 40, on rock shaft.
Move feed bar carrier and rock shaft so that move
ment of feed dog is equidistant from front and rear
edges of throat plate slots.
Securely tighten hex-head screw.
Check linkage for freedom of movement to reduce
wear and insure maximum efficiency.
©
FEED BAR CARRIER
ROCK SHAFT
Fig. 40. Feed Bar Linkage
HEX-HEAD SCREW
SETTING THE PRESSER BAR HEIGHT
When presser foot rests firmly on throat plate, with
feed dog below throat
plate, there should be a slight
clearance between guide and lifting bracket, shown in
Fig. 41.
When presser foot is raised to highest point end
needle bar is at bottom of its stroke, top of presser
foot should not contact needle bar.
To adjust for clearance between guide bracket and
lifting bracket, remove large plug from face plate and
loosen clomp screw thus made
accessible.
This clamp screw is shown in Fig. 41. Face plate
is removed in this illustration only to show entire
presser bar assembly.
Raise or lower guide bracket as required.
Make certain that presser bar is correctly turned,
with needle centered in needle slot (or between the
toes) of presser foot then securely tighten clamp screw.
16
CAUTION: Whenever guide brocket has been moved
on presser bar, inspect the check spring for correct
setting as previously instructed.
CLAMP
SCREW
CLEARANCE
LIFTING
BRACKET
0^0
GUIDE
BRACKET
Fig. 41. Presser Bar Assembly
From the library of: Superior Sewing Machine & Supply LLC