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.
From the library of: Superior Sewing Machine & Supply LLC

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.
From the library of: Superior Sewing Machine & Supply LLC

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.
From the library of: Superior Sewing Machine & Supply LLC

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
From the library of: Superior Sewing Machine & Supply LLC

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.
From the library of: Superior Sewing Machine & Supply LLC

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
From the library of: Superior Sewing Machine & Supply LLC

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.
From the library of: Superior Sewing Machine & Supply LLC