Singer 281-5 User manual

Form 21315
(1064)
SINGER
Service Manual
Machines
281-5, 281-6, 281-20, 281-22,
281-23 and 281-24
Regulation View - Machine 281-24
THE SINGER COMPANY
Copyright ® hy The Singer Compony
Copyright Under International Copyright Union
All Rights Reserved under Inter-American Copyright Union
*A Trademark o( THE SINGER COMPANY
Printed In U. S. A.
From the library of: Superior Sewing Machine & Supply LLC

DESCRIPTION 3,4
INSTALLATION 5
LUBRICATION AND CLEANING 6, 7
OPERATION 7-13
ADJUSTMENT 14-25
PARTS Rear of Manual
is
Bed-Raising Plate 3, 16, 18, 20
Bobbin, Removal and Replacement 10
Bobbin Case, Removal and Replacement 10
Bobbin Cose, Threading 10
Bobbin Case Holder, Removal and Replacement 20
Centralizing the Feed Dog 21, 22
Check Spring, Height Setting 21
Check Spring, Tension Adjustment 21
Check Spring, Timing 21
Cleaning 7, 20
Close-Coupled Puller Feed ....4, 24, 25
Compound Feed 4, 13, 16
Description of Machines 3, 4
Determining Thread Twist 7
Disc Tension 3
Face Plate Removal 14
Federal Stitch Type 3
Feed Bar Eccentric Hinge Pin 22, 23
Feed Bar Linkage 22
Feed Dog, Centralizing 21, 22
Feed Dog, Height Settings 22, 23
Feed Roller, Changing 24
Feed Roller, Correct Height 25
Feed Eccentric Stop Screws Available 23
Feed Leveling 22, 23
Feed, Synchronizing 25
Feed Wheel, Changing 24
Filter (Sewing Hook Lubrication) 6
Gripper Feed 3, 12, 25
Guard, Needle 20
Guard, Needle Thread 3
Hook Section 20
Installation 5
Knee Lifter 3, 5
Knife Sharpening 15
Length of Stitch 3, 4, 12, 13, 23
Leveling the Feed 22, 23
Lint Wiper 3
Lower Threading 10
Lubricating System 3, 5-7
Lubrication 5, 6
Machine Base 5
Machine Pulley 3
Magnet on Oil Pump 7
Materials Sewn 3, 4
Maximum Stitch Length 3, 4, 23
Needle Bar Bushing (Lower), Setting 16
Needle Bar Frame, Setting 16
Needle Bar Height, Setting 16, 17
Needle Bar Stroke 3, 4
Needle Clearance with Hook, Setting 18, 19
Needle Feed 3, 4, 13
Needle Guard at Loop-taking Time 20
Needle Guard, Stringing 20
Needle Position in Relation to Throat Plate 14, 16
TO ALL WHOM IT MAY CONCERN:
Needle Recommended 3, 8
Needle, Setting 8
Needle Stop 16
Needle Thread Guard 3
Needle Threading 9
Needle Thread Tension Releaser 24
Oil Flow Regulator 6
Oil Flow Window 3, 6
Oil Pump 7
Oil Recommendations 6
Oil Reservoir 3, 5
Oil Retaining Collar 18
Oil Spray Pattern 6
Parts Charts Rear of Manual
Pendant Link Feed 3
Presser Bar Height, Setting 23
Presser Bar Lift.... 3, 4, 23
Presser Foot Pressure, Adjustment 11
Preventing Unauthorized Changes in Stitch Length 13
Position Finger, Settings 19
Puller Feed 3, 4, 12, 24, 25
Pressure of Roller Pressers 11
Radial Position of Sewing Hook 18
Regulator Button (Stitch Length) 12, 13
Reservoir 3, 5
Sewing Hook Clearance with Needle, Setting 18, 19
Sewing Hook Filter Screw 6
Sewing Hook Lubrication 6
Sewing Hook, Oiling Wick 6
Sewing Hook, Timing 18
Side-Wheel Puller Feed 4, 12, 24, 25
Space at Right of Needle 3
Speed Recommendations 3, 7
Stitch Length, Maximum 3, 4, 23
Stitch Length, Preventing Unauthorized Changes 13
Stitch Length, Regulation 12, 13
Stop Screws (Feed Eccentric) 23
Stringing the Needle Guard 20
Synchronizing the Feed 35
Take-up Lever Movement 31
Tension of Check Spring, Adjustment 31
Thread 7
Threading, Lower 10
Threading, Upper 8, 9
Thread Tensions 11
Timing 18-25
Timing-Indicator Pin 17, 18
Thread Twist, Determination 7
Top-Driven Gripper Feed 3, 12, 25
Trimming Knife, Setting 15
Trimming Margin 3, 14
Upper Threading 8, 9
Unauthorized Changes in Stitch Length, Preventing 13
V-belt 3
Vertical Trimmer 3, 13, 15
Wick, Sewing Hook 6
The improper placing or renewal of the Trademark SINGER* or any other of the Trademarks of The Singer Company
(all of which ore duly Registered Trademarks) on any machine that has been repaired, rebuilt, reconditioned, or altered
in any 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 of Class 281- are high speed, single
needle, lockstitch machines designed for sewing ma
terials ranging from light weight to heavy weight.
Among the varieties covered in this manual are
puller-feed and needle-feed machines, top-gripper
machines and machines that perform simultaneous
trimming and stitching.
All of these machines produce outstanding straight
line stitching in a wide range of wash-and-wear, syn
thetic and natural fabrics.
Generol Features
Federal stitch type 301.
Balanced, air cooled, rotating hook. Horizontal
Lint wiper keeps lint and abrasive matter from ac
cumulating on hook.
Drop feed
consists 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 oil reservoir.
Independent light fixture mount.
Improved needle thread guard and other thread hand
ling ports. Disc tension.
Machinepulley 147139 for 3/8 inch V-belt.
Space at right of needle, 11 inches.
Machine Varieties
Machine 281-5, Vertical Trimmer
Medium weight and heavy weight fabrics.
Needle bar stroke, 1-13/64 inches
Presser bar lift, 5/16 inch.
Knife bar stroke, 5/16 inch.
Maximum stitch length, with regular fittings, 5-1/2
stitches per inch.
Needle, Catalog 1515 {16x95).
Bed-raising plate sets flush with top of throat
plate.
Regularly fitted to trim 1/8 inch from line of stitch
ing. Extra cutting bar and presser foot supplied for
3/16 inch.
When specified on order, machines can be fitted
for 1/16, 3/32, 5/32, 3/16 or 1/4 inch trim margin.
Extra cutting bar and presser foot furnished in each
instance will be next size larger than that ordered.
When 1/4 inch (widest trim margin) is requested,
two sets of this size will be supplied with machine.
Speed, 5000
stitches per minute.
Mochine 281-6, Top Gripper
Collar and cuff operations on light weight to medium
weight fabrics.
Top driven gripper feed. Top feed intermittently
driven by linkage actuated through countershaft.
Countershaft driven by eccentric on arm shaft.
Eccentric adjustable to obtain optimum relationship
between top and bottom feed. Top feed designed to
grip fabric at same moment that bottom feed rises
to moke contact and to travel with bottom feed
during its entire front to rear feeding motion. Top
feed then returns (in raised position above ma
terial) to beginning of next grip-feeding movement.
Needle bar stroke, 1-3/16 inches.
Presser bar lift, 3/16 inch.
Maximum stitch length, with regular fittings, 5-1/2
stitches per inch.
Needle, Catalog 1955
Speed, 5000
stitches per minute.
From the library of: Superior Sewing Machine & Supply LLC

DESCRIPTION (continued)
Machine 281-20, Close-coupled Puller Feed
Light weight to medium weight fabrics.
Needle bar stroke, 1-13/64 inches.
Presser bar lift, 5/16 inch.
Maximum stitch length, with regular fittings, 5-1/2
stitch per inch.
Needle, Catalog 1955.
Close-coupled puller feed 1-9/16 inches behind
needle. Feed roll intermittently actuated by coupling
through set of gears, countershaft, clutches and
eccentric. Eccentric independently adjustable to
bring motion of feed roll in unison with motion of
feed dog.
Speed, 5000 stitches per minute.
Machine281-22,
Needle Feed
Light weight to medium-heavy weight fabrics.
Needle bar stroke, 1-13/64 inches.
Presser bar lift, 5/16 inch.
Maximum
stitch length, with regular fittings, 10
stitches per inch.
Needle, Catalog 1955.
Compound feed mechanism, consisting of needle
feed and drop feed, insures positive feeding of two
or more plies of material.
Improved stitch regulating mechanism. Needle feed
regulator con be locked to permit simultaneous ad
justment of needle feed and drop feed.
Speed, 5000 stitches per minute.
Machine 281-23, Side-wheel Puller Feed
Light to medium weight fabrics.
Needle bar stroke, 1-13/64 inches.
Presser bar lift, 5/16 inch.
Maximum stitch length, with regular fittings, 5-1/2
stitches per inch.
Needle,Catalog 1955.
Side wheel feed roll independently
adjustable to
bring motion of feed roll in unison with motion of
feed dog.
Speed, 5000 stitches per minute.
Machine 281-24 Needle Feed
Light to medium weight fabrics.
Needle bar stroke, 1-9/64 inches.
Presser bar lift, 9/32 inch.
Maximum stitch length, with regular fittings 10
stitches per inch.
Needle, Catalog 1361 (88x9)
Compound feed mechanism, consisting of needle
feed and drop feed, insures positive feeding of
two or more plies of material.
Improved stitch regulating mechanism. Needle feed
regulator con be locked to permit simultaneous
adjustment of needle feed and drop feed.
Speed, 5500 stitches per minute.
From the library of: Superior Sewing Machine & Supply LLC

GASKET
PLUNGER
LOW MARK
HIGH MARK
OIL
RESERVOIR
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 base.
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.
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.
STOP SCREW LOCK NUT ROCK SHAFT
CLAMP SCREWS
LIFTER LEVER
REAR STOP DOG
KNEE PLATE I
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 rate of flow. Then open the bed slide,
hold 0 piece of paper under the hook and run the ma
chine for about ten
seconds. There should be a distinct
Iine 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
POSIT,OH
BRACKET SCREW OIL FLOW REGULATOR
Fig. 5. Oil Flow Regulator
SEWING HOOK
OIL FLOW REGULATOR
a U-
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.
Reploce wick if necessary.
Assemble sewing hook and position finger to ma
chine.
Re-check oil flow as previously instructed.
From the library of: Superior Sewing Machine & Supply LLC

Sk^ING
Using a short bristle brush (not point of scissors or
other sharp instrument), remove lint and other waste
from around sewing hook, from between feed rows and
underside of throat plate and from all other operating
points.
CLEAN
Tilt machine back on hinges. Wrap clean rog around
magnet, shown in Fig. 7, on oil pump body and pull
accumulated foreign particles
from magnet.
Wipe exterior of machine dry with a soft cloth.
From the library of: Superior Sewing Machine & Supply LLC

MOVE TO
HIGHEST POINT
LOOSEN SCREW
INSERT NEEDLE UP
AS FAR AS POSSIBLE
AND TIGHTEN SCREW
LONG GROOVE
Fig. 9. Machine 281-5
OOVE^^
Fig. 10. Machines 281-6 and 281-20
LONG
GROOVE
MOVE TO
"^HIGHEST POINT
LOOSEN SCREW
INSERT NEEDLE UP
AS FAR AS POSSIBLE
AND TIGHTEN SCREW
TO
MOVE TO
HIGHEST POINT
LOOSEN SCREW
INSERT NEEDLE UP
FAR AS POSSIBLE
AND TIGHTEN SCREW
LONG GROOVE
Fig. 11. Machines 281-22 and 281-24
MOVE TO
HIGHEST POINT
LOOSEN SCREW
LONG GROOVE
INSERT NEEDLE UP
FAR AS POSSIBLE
AND TIGHTEN SCREW
Fig. 12. Machine 281-23
Machine 281-5
Use SINGER* Needle, Catalog 1515 (16x95), in
sizes ranging from 11 to 22.
Machines 281-6, 281-20, 281-22 and 281-23
Use SINGER* Needle, Catalog 1955, in sizes rang
ing from 8 to 22.
Machine 281-24
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 Figs.
9 to 12.
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.
UPPER THREADING
Turn machine pulley over toward operator until
needle bar is at highest point.
Pass thread through threading points indicated in
Figs. 13 to 18, page 9. Draw approximately two inches
of thread through needle eye with which to start sewing.
From the library of: Superior Sewing Machine & Supply LLC

UPPER THREADING
THREADING THE NEEDLE
ill
From the library of: Superior Sewing Machine & Supply LLC

LOWER THREADING
1. OPEN LATCH—^
2. HOLD LATCH
AND PULL y^v
CASE FROM--'"''''''^'^»^'>^
HOOK ^
Fig. 19. Removing Bobbin Case
3. RELEASE LATCH ,
4. BOBBIN DROPS OUT
Fig. 20. Removing Bobbin
SLOT NEAR TOP
Fig. 21. Replacing Wound Bobbin
1. PULL THREAD
INTO SLOT-—^
2. DRAW THREAD
DOWN AND
UNDER SPRING
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 case from machine as shown in Fig. 19.
Release latch and bobbin will drop out of case, as
shown in
Fig. 20.
Threading Bobbin Case
Hold bobbin so that thread will unwind in the direc
tion shown in Fig. 21. Hold bobbin case as shown and
place bobbin into it.
Pull thread into slot and under tension spring,
shown in Fig. 22, 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 bock until
latch catches near end of stud as shown in Fig. 23.
Draw about two inches of thread from bobbin to start
the sewing.
DELIVERY EYE
3. TURN BOBBIN
CASE OVER.
DRAW THREAD
UP AND INTO
DELIVERY EYE
Fig. 22. Threading Bobbin Case
1. HOLDING LATCH, REPLACE
BOBBIN CASE ON STUD.^
2. RELEASE LATCH.
3. PRESS BACK, UNTIL LATCH
CATCHES GROOVE IN STUD.
From the library of: Superior Sewing Machine & Supply LLC

ADJUSTING THE TENSION
Tension on thread should be as light as possible
while still sufficient to set stitches correctly in mate-
Regulate needle thread tension, os instructed in
Fig. 24. Make certain presser foot is DOWN during
tension adjustment.
Tighten lock nut to maintain tension adjustment.
Regulate bobbin thread tension as instructed in
Fig. 25.
ADJUSTING THE PRESSER FOOT PRESSUR
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. 26, with presser
foot down.
On all Mochines, except Machine 281-5: Pressure
regulating thumb screw is fitted with lock nut. Loosen
this lock nut before adjusting pressure.
When correct pressure is obtained, tighten lock nut
to maintain adjustment.
Machine 281-5; To adjust pressure, turn regulating
screw (with screwdriver) upward for
less pressure, or
downward for more pressure, as required.
ADJUSTINGTHE PRESSURE
OF THE ROLLER PRESSERS
(MACHINES 281-20 AND 281-23)
Pressure of the roller pressers on these machines
should be
as light as possible, while still sufficient
to insure correct feeding.
Regulate as instructed in Figs. 27 and 28.
MORE TENSION
1. LOOSEN^
LOCK NUT
2. TURN
k. THUMB NUT
LESS TENSION
Fig. 24. Needle Thread Tension
TURN
REGULATING
SCREW s
MORE TENSION
LESS TENSION
Fig. 25 Bobbin Thread Tension
MORE I
PRESSURE
LESS
PRESSURE
LOOSEN I
LOCK NUT
Fig. 26. Presser Foot Pressure
MORE PRESSURE
LESS PRESSURE^
I L--^
Fig. 27. Regulating Pressure of
Roller Presser on Machine 281-20 M
MORE PRESSURE
PRESSURE
Fig. 28. Regulating Pressure of
,Roller Presser on Machine 281-23
From the library of: Superior Sewing Machine & Supply LLC

REGULATING THE STITCH LENGTH
STOP MACHINE 3. TURN MACHINE PULLEY
2. DEPRESS BUTTON TOWARD YOU SLOWLY
/'
—7^ 'i '((JhMU
V ' 5. THEN TURN MACHINE
PULLEY TO DESIRED
4. UNTIL BUTTON STITCH LENGTH AND
DROPS INTO NOTCH RELEASE BUTTON
Fig. 29. Machine 281-5
FEED DOG STITCH LENGTH BUTTON
TOP-GRIPPER STITCH LENGTH BUTTON
Fig. 30. Mochlne 281-6
FEED DOG STITCH LENGTH BUTTON
FEED ROLL STITCH LENGTH BUTTON
Fig. 31. Machines 281-20 and 281-23
Changes in stitch length should never be attempted
while the machine is running.
See pages 3 and 4 for information on maximum
stitch length for your machine.
CAUTION: Stitch length
setting should never ex-
ceedcopacity of fittings in use.
Machine 281-5
Regulate the stitch length, as instructed in Fig. 29.
Button mentioned in Step 4, Fig. 29, drops into
notch with an audible click.
Machine 281-6
1. Remove needle from machine.
2. Depress feed dog stitch length button, shown in
Fig. 30.
3. Turn machine pulley over toward—you until button
drops (audible click).
4. Turn machine pulley to
desired stitch length and
release button.
5. Depress top-gripper stitch length button.
6. Turn machine pulley toward you slowly—until button
drops.
7. Turn machine pulley to same stitch length as feed
dog is set.
Never depress either button while machine is running.
Make certain both buttons are disengaged before start
ing machine.
Machines281-20 and 281-23
1. Stopmachine.
2. Depress feed dog stitch length button, shown in
Fig.31.
3. Turn machine pulley over toward you slowly—until
button drops (audible click).
4. Turn machine pulley to
desired stitch length and
release button.
5. Depress feed roll stitch length button.
6. Turn machine pulley toward you slowly—until button
drops.
7. Turn machine pulley to desired stitch length and
release button.
Never depress either button while machine is running.
Make certain both buttons are
disengaged before start
ing machine.
From the library of: Superior Sewing Machine & Supply LLC

REGULATING THE STITCH LENGTH (continued)
Machines 281-22 and 281-24
1. Remove needle from machine.
2. Depress plunger, shown in Fig. 32, on top of arm.
Continue to hold plunger down - - -
3. Turn machine pulley over toward
you--- until
plunger drops (entering notch in arm shaft eccen
tric).
4. Turn plunger, toward right or left, 1/4 turn, to lock
position.
5. Depress stitch length button, shown in Fig. 32.
6. Turn machine pulley over toward you - - • until
but
ton drops.
7. Turn machine pulley to desired stitch length and
release button.
8. Turn plunger toward right or left until it releases,
springing upward.
TO PREVENT JAMMING OF MACHINE: PLUNGER MUST
ALWAYS BE DISENGAGED BEFORE STARTING MACHINE.
Never depress either button or plunger while machine
is running.
Never turn machine pulley with plunger in locked posi
tion unless stitch length button is depressed also.
PREVENTING UNAUTHORIZED
CHANGES IN STITCH LENGTH
Stitch regulator button may be removed by loosening
the arm top cover screws and removing arm top cover,
as shown in Fig. 33.
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.
TO OPERATE THE TRIMMER /
(MACHINE 281-5)
To engage the vertical trimmer, push DOWN on
lever, shown in Fig. 34.
To raise the knife out of the way, push IN button
on face, as shown.
FROM THIS POINT ON, INSPECT AND ADJUST
THE MACHINE, WHEN IT IS REQUIRED, IN THE
ORDER GIVEN.
STITCH LENGTH BUTTON
PLUNGER
LOCK i
Fig. 32. Reguioting the Needle Feed and Drop Feed,
Machines 281-22 and 281-24
BUTTON
RETAINING
RING
Fig. 33. Removing Stitch Length Regulator Button
PUSH IN
TO RELEASE
r m
PUSH DOWN:
TO ENGAGE
r Fig. 34. Operating the Trimmer on Machine281-5
From the library of: Superior Sewing Machine & Supply LLC

THE FACE PLATE (MACHINE 281-5)
TRIMMER
RELEASE
LEVER
% •
\*
Fig. 35. Removing the Face Plate
(Machine 281-5)
KNIFE
BAR
CRANK
POSITIONING NEEDLE CORRECTLY
IN NEEDLE HOLE OF THROAT PLATE
CUTTING BAR (MACHINE 281-5)
The specialized face plate on machine 281-5 re
quires a small amount of manipulation to be safely
removed and replaced.When correctly placed the trim
mer release lever is hooked under the knife bar crank
shown in Fig. 35.
Face plate may be removed by loosening its four
screws and gently pulling face plate outward to sepa
rate gasket from casting. Then draw face plate down
ward to
disengage release lever from knife bar crank
shown in Fig. 35.
Replace face plate with an upward motion so that
release lever is engaged beneath knife bar crank.
Make certain that screw holes in gasket align with
their respective screw holes in face plate. Securely
tighten the four face plate screws.
SETTING THE TRIMMING MARGIN
(MACHINE 281-5)
Turn machine pulley until needle point rises just The distance from the trimmed edge to the line of
above needle hole in throat plate cutting bar.
Loosen
the two screws B, Fig. 36 and locate throat
plate so that needle will rise and fall in center of
needle hole in throat plate cutting bar.
Tighten the two screws B.
CUTTING
BAR V
THROAT
PLATE^
SLIDE SCREW
UPPER
KNIFE
Fig. 36. Needle Location in Throat Plate
Cutting Bar (Machine 281-5)
stitching is determined by the throat plate cutting bar
used. Each throat plate cutting bar is designed for
but one trimming margin. (See "DESCRIPTION" on
page 3.)
The trimming margin is measured from the center
of the needle hole to the cutting edge of the throat
plate cutting bar.
To
change trimming margin: Loosen slide screw
and move throat plate slide, shown in Fig. 36, toward
the right. Remove two screws A, Fig. 36 and presser
foot screw. Change throat plate cutting bar and presser
foot as required, fastening cutting bar with two screws
A. Return throat plate slide to its normal position
(toward the left against cutting bar) and tighten slide
After changing trimmer parts, always check knife
adjustment, as instructed on page 15.
From the library of: Superior Sewing Machine & Supply LLC

SETTING UPPER KNIFE IN RELATI
TO THE THROAT PLATE CUTTING B,
(MACHINE 281-5)
Press down on lever shown in Fig. 37, lowering
knife.
Turn machine pulley until upper knife is at its
lowest position.
Loosen the two lock nuts behind screws shown
in Fig. 37, above upper knife. Move knife holder to
bring upper knife
as close as possible to cutting bar,
as shown. Securely tighten two screws and lock nuts,
previously loosened.
Loosen two
screws B, Fig. 37. Using a screwdriver
as shown, press throat plate cutting bar firmly against
upper knife, setting cutting bar parallel to blade of
knife, as shown in Fig. 37. Securely tighten two screws
B.
Check to make certain upper knife releases readily
when button on face olate is oushed IN.
lecheck needle locatior
•e-set, if necessary as i
Then check and re-set
TO ADJUST HEI
(MACHIN
urn machine pulley o\
i is at its lowest posit
37. Raise or lower the
he n shar
per ling the upp
er 1
be vel sh
ow
n in Fig. 38
is
ct enaaa
emi snt of upper
and
e hole
f page
ructed
upper
ws C,
red to
' 1/64
a bar.
PRESS
LOOSEN
LOCK N
BEHIND THESE
TWO SCREWS
From the library of: Superior Sewing Machine & Supply LLC

POSITIONING NEEDLE IN RELATION TO THROAT PLATE
AND FEED DOG (MACHINES 281-22 AND 281-24)
NEEDLE
HOLE V
PINCH
SCREW
NEEDLE BAR
FRAME
Fig. 39. Positioning the Needle (front to rear)
on Machines 281-22 and 281-24
THROAT PLATE
SEATv
BOTTOM OF
LOWER NEEDLE
BAR BUSHING
2.599"
Fig. 40. Correct Setting: Needle Bar Bushing
THROAT PLATE
SEAT ^
NEEDLE STOP
J...
0.866" (281-24)
1.031" OTHERS
Fig. 41. Setting Needle Bar at Correct Height
(Using Gauge Distance)
Needle should not contact surfaces of throat plate
or feed dog.
Needle, needle bar and needle bar frame may be
positioned forward or backward, after loosening pinch
screw, shown in Fig. 39.
To adjust, set feed eccentrics for longest stitch,
as instructed on page 13. Insert needle correctly in
needle bar. Remove face plate and slide plate.
Loosen pinch screw and move needle bar frame,
as required. Securely tighten pinch screw and replace
all parts previously removed.
SETTING THE LOWER NEEDLE BAR BUSHING
ON COMPOUND FEED MACHINES 281-22 AND 281-24:
The lower needle bar bushing is integral with the
needle bar frame and does not require separate setting.
ON ALL OTHER MACHINES: Gauge distance from
throat plate seat to bottom of lower needle bar bushing
is 2.599 inches.
Raise or lower needle bar bushing, as required to
obtain
correct height setting, after loosening bushing
set screw shown in Fig. 40.
SETTING THE NEEDLE BAR HEIGHT
(without using timing mark)
Machine 281-5: Remove bed
raising plate.
All Machines: 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. 41, is - - -
0.866 inch for Machine 281-24
1.031 inches for all other Machines.
To set needle bar height, loosen the needle bar
clamping screw shown in Fig. 41. Raise or lower
needle bar as may be required. Securely tighten clamp
ing screw. Replace all parts previously removed.
When replacing face plate, make certain that screw
holes in gasket align with screw holes in face plate,
to avoid injury to
gasket and subsequent oil leakage.
From the library of: Superior Sewing Machine & Supply LLC

SETTING THE TIMING-INDICATOR PIN
(MACHINES 281-22 AND 281-24)
Set needle bar at correct height, as instructed on
page 16.
When needle bar is at its lowest point {during ro
tation of machine pulley) the point of timing indicator
pin should be level with UPPER TIMING MARK on
needle bar, as shown in Fig. 42.
To
adjust indicator pin, loosen set screw, shown
in Fig. 42, in needle bar frame and raise or lower
pin, as required. Securely tighten set screw.
SETTING THE NEEDLE 8AR HEIGHT
(Using Upper Timing Mark)
When lower needle bar bushing (or timing-indicator
pin on Machines 281-22 and 281-24) is correctly set
as previously instructed, the timing marks on the
needle bar may be used for setting and timing the
machine. If needle bar height is subsequently dis
turbed, needle bar may be quickly restored to its cor
rect height as follows - - -
MACHINES 281-22 AND 281-24: Turn machine pulley
slowly until
needle bar is at its lowest point. Loosen
needle bar clomping screw shown in Fig. 42, and
raise or lower needle bar, as required, to bring UPPER
TIMING MARK level with pointer on timing-indicator
pin, as shown in Fig. 42. Securely tighten clamping
ALL OTHER
MACHINES: Turn machine pulley slowly
until needle bar is at its lowest point. Loosen needle
bar clamping screw, shown in Fig. 43, and raise or
lower needle bar,
as required, to bring UPPER TIMING
MARK level with bottom of lower needle bar bushing,
as shown in Fig. 43. Securely tighten clamping screw.
NEEDLE BAR
FRAME--.' ^
NEEDLE BAR
CLAMPING
SCREW
SET SCREW
INDICATOR PIN
AT
LOWEST
POINT
Fig. 42. Setting Needle at Correct Height on
Machines 281-22 and 281-24
CLAMPING
SCREW ^
UPPER
TIMING'
MARK
® 1®
AT
LOWEST
POINT
LOWER
NEEDLE
BAR
BUSHING
Fig. 43. Setting Needle Bar at Correct Height
on all Machines, except 281-22 and 281-24
From the library of: Superior Sewing Machine & Supply LLC

CLEARANCE
ABOVE EYE
'LOWER TIMING
MARK LEVEL
WITH BOTTOM
OF LOWER
NEEDLE BAR
BUSHING
HOOK POINT AT
CENTER OF
NEEDLE
Fig. 44. Hook Point at Center of Needle
HOOK
BODY «=
SCREWS
OIL
'retaining
COLLAR
Fig. 45. Hook Body Screws
NOTE-PAPER
FLAT OF
HOOK POINT
Fig. 46, Clearance Between Needle and Hook
TIMING THE MACHINE
Timing the machine consists of first adjusting the
rodiol position of sewing hook with relation to move
ment of needle bar and needle thread take-up lever, to
moke
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
MACHINE 281-5: Remove bed-raising plate.
MACHINES 281-22 AND 281-24: Make certain that
timing-indicator pin is correctly set in needle bar
frame, as instructed on page 17.
ALL MACHINES: 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. 44. (On Machines 281-22 and 281-24,
LOWER TIMING MARK should be level with timing-
indicator pin shown in Fig. 42, page 17).
At this position, point of sewing hook should be at
center of needle, as shown in inset. Fig. 44.
Loosen two hook body screws shown and turn hook
on shaft
as required to bring point of hook to center of
needle. See Fig. 45.
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
MACHINE281-5: Remove bed-raising plate.
ALL MACHINES: Remove si ide plate, throat plate and
bobbin case.
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
OS 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. 46,
is sufficient.
From the library of: Superior Sewing Machine & Supply LLC

SETTING THE CLEARANCE BETWEEN
NEEDLE AND HOOK POINT (Continued)
To move hook point toward or away
from needle,
loosen the two bevel gear screws shown in Fig. 47
and loosen bushing set screw shown in Fig. 48.
MAKE CERTAIN THAT BEVEL GEARS ARE
KEPT IN MESH CONSTANTLY UNTIL THEIR SCREWS
ARE SECURELY RETIGHTENED.
Using a light mallet and a 1/4 inch brass drift pin,
move hook assembly toward or away from needle as
required. Figs. 48 and 49 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 same time, moving hook shaft *bevei gear
toward sewing hook end of shaft.
DO MOT DAMAGE
LOOSEN
BUSHING
SET SCREW
^\JJ 1/4" BRASS
DRIFT PIN
TAP VERY
LIGHTLY
TOWARD
NEEDLE.
Fig. 48. Position of Drift Pin when
Moving Hook Toward 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. 50, 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.
HOOK
SHAFT
BEVEL
GEAR^
ALWAYS
KEEP
GEARS
IN MESH-
BEVEL
GEAR
SCREWS
-1
-2
Fig, 47. Bevel Geor Screws
Tighten screw 1, Fig. 47 on bevel gear. Securely
tighten bevel gear screw 2, Fig. 47.
Replace all parts previously removed.
Check thread clearance between position finger
and bobbin case, as instructed next.
TAP VERY
LIGHTLY
AWAY r.
FROM NEEDLE
1/4" BRASS
DRIFT PIN
LOOSEN
BUSHING
SET SCREW
DO NOT
HIT
BRIDGE
Fig. 49. Position of Drift Pin when
Moving Hook Away from
Needle
BOBBIN
CASE
HOLDER
POSITION
FINGER
Vf
a)r-^
.018" TO .022"
.CLEARANCE
POSITION
FINGER
SCREW
Fig. M^Position Finger
From the library of: Superior Sewing Machine & Supply LLC

POSITION
FINGER
SLOTn^
POSITION
FINGER^
FEED BAR
HOOK POINT
HOOK BODY-
STRINGING THE NEEDLE GUARD
HOOK POINT
NEEDLE GUARD
Incorrect:
Stringing Required
HOOK
POINT
LARGE
NEEDLE
BOBBIN
CASE
HOLDER
NEEDLE
GUARD
BOBBIN'
Fig. 51. Needle Guard at Loop-Taking Time
3 SMALL
SCREWS
HOOK SECTION
Fig. 52. Hook Section
POSITION FINGER
SLOT ON THREAD
GUARD
BOBBIN CASE
HOLDER
HOOK POINT
NEEDLE GUARD
y Incorrect
^ Too Much Metal
Removed from Guard
Fig. 53. Bobbin Cose Holder
The needle guard on the bobbin case holder, shown
in
Figs. 51 and 54, should prevent needle from con
tacting hook or bobbin case at any time. See Fig. 51
(A) for correct relationship. When large needles {size
20 or larger) are used, needle guard may deflect needle
too far toward left resulting in damage to needle. See
Fig. 51 (B). To avoid this, it may be necessary to
string the needle guard in accordance with the follow
ing instructions.
MACHINE 281-5: Remove bed-raising plate.
ALL MACHINES: Remove needle, slide plate, throat
plate and bobbin case from machine
Turn machine pulley until feed bar, Fig. 52, is at
its highest point.
Remove position finger shown in Fig. 52.
Turn hook body to position shown in Fig. 52 and
remove three small screws and hook section shown.
Turn bobbin case holder until position finger slot
on thread guard is at location shown in Fig. 53. 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. 54.
EXTREME CARE should be taken to avoid removal
of too much metal as this may permit needle to strike
hook. See Fig. 51 (C). Bobbin case holder will then
need replacement.
Clean bobbin
case holder thoroughly before re
placing it in hook body.
Replace all parts in reverse order instructed for
removal.
NEEDLE
.GUARD
Fig. 54. Stringing
l/8"#320 EMERY
Needle Guard
From the library of: Superior Sewing Machine & Supply LLC