Singer 271K11 User manual

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271K11
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From the library of: Superior Sewing Machine & Supply LLC

Form K8560 (970) Printed in Great Britain
Copyright © 1970 by The Singer Company
All rights reserved under Inter-American Copyright Union
Copyright under International Copyright Union
From the library of: Superior Sewing Machine & Supply LLC

General index
Page
3
Page
Needle bar frame play
32
Description of Machines
Needle bar height
32
4
Needle plate centralising 32
Safety devices 34
Varieties of Machines
4
Safety tripping lock 34
Sewing hook 34
Sewing hook setting 34
Instaiiation and Operation
Belt
5
Sewing hook timing 34
6
Sewing safety lock 34
Starting lever rod 34
Buttonhole length
6
Stop cam face and interlocking rod clearance
34
Cleaning
6
Stop cam gear and pinion play
36
Completing unfinished buttonhole
6
Stop motion 36
Gear identification
6
Tension releaser (top of arm)
36
Gear changing and selection
8
Thread breaking or fraying—elimination
36
Internal oil passage alignment
6
Top cord finger 38
Lubrication
12
Upper thread cutting and clamping blades 40
Machine pulley
12
Needles and needle setting
12
Removal and Replacement
Oil flow to hook regulation
12
43
Speed
12
Knife
44
Stitching over twice on the same buttonhole
12
Stop cam gear spring
44
Thread
12
Under thread cutting blades
46
Threading
14
Upper thread cutting and clamping blades
46
Thread tensions
18
Two speed belt shifter
18
Timing and Setting
21
opeciai insiruciions jot iivi^
Machines 49
Automatic knife bar disengaging lever
22 Barring stitch width
50
Barring
22
Bight stitch width
50
Barring tension plate actuator
24
Driving arm safety
50
Belt shifter 24
Needle thread pull-off
50
Bight width 26
Needle thread tension release
50
Bobbin case stop. Horizontal position
26
Sewing safety lever setting
50
Bobbin case stop. Vertical position
26
Tie stitch centralising
52
Clamp check centralising
26
Tie stitch width
52
Clamp check clearance with needle
26
Upper thread cutting cam follower setting
52
Cutting space
28
Upper thread cutting cam timing
52
Driving lever spring tension
28
Feed wheel tripping points
28
Parts Lists
57
Interlocking rod guide and lock pin clearance
30
Interlocking rod tension
30
271 K11
58
Knife bar height
30
271 K13
104
Knife holder guide stud loct-tion
30
271 KX1
112
Knife slot in needle plate alignment
32
271K211 116
Latch tripping plate
32
271 K12
120
Needle and knife alignment 32
271K14
168
Needle bar frame height 32
271K24
216
Numerical List of Parts
219
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Description
Ciass 271K Machines
Top quality lockstitch buttonholers in light and medium
weight materials at speeds up to 3,000 stitches per minute.
General Characteristics
Single needle Catalogue 1526.
Lockstitch.
Automatically lubricated rotary sewing hook.
Visual gauge gives easy check on amount of oil in reservoir.
Fast, completely automatic sewing cycle.
Link take-up.
The cycle is completed with the take-up just below its
highest point.
The buttonhole is automatically cut during the last stitch
of the cycle.
At the completion of the cycle the initial pressure on the
clamp lifting mechanism triggers off the needle thread
cutting and clamping blades so that the needle thread'
is cut and then retained in the clamp check. As the clamp
check is raised the bobbin thread is cut.
Tying stitches made at beginning and end of each button
hole provide perfect starting stitches and a securely
fastened bar at finish.
Needle thread re-trimming device gives uniformly trimmed
thread ends.
Positive, gear-driven, continuous feed, spaces stitches
evenly around buttonhole giving neat uniform stitch
appearance under all conditions.
Stitch gear changes made without use of special tools.-
Unique two speed drive automatically slows arm shaft to
half, and the stop cam to quarter, operating speed before
entering stop position. This action ensures a positive
stop with minimum strain on the stop motion.
Shock reducing knife bar stop provides cushion of air
enabling knife bar to return quietly and safely after cutting
buttonholes.
Safety clamp lock prevents operator raising work clamp
until buttonhole cycle is completed.
Hand ratchet device enables operator to restart stitching
at any part of buttonhole.
Bobbin winder attached to belt guard.
Double angle buttonhole knife provides maximum clear-.
ance above the work clamp when sewing heavy materials
and gives an improved cleaner cut.
Needle bar stroke: 1-23/64 inch (34.5mm).
Clearance under clamp:
3/8 inch (9.5mm).
Machines can be tipped to left or rear for servicing.
Special Features of Machine Varieties
Class
Applications
Stitch
Length of
Buttonhole
Style of
Ends
Knives
Speed
271 K11
Dress and sports shirts,
dresses, pyjamas, skirts
and other garments
Straight
purl or
whip
stitch
3/8 inch to 3/4 inch
(9.5 to 19mm)
Supplied up to
1inch (25.4mm)
Square or
wide bar
3/8 inch to 1 inch
(9.5 to 25.4mm)
in steps of
1/16 inch (1.6mm)
3.000
stitches per
minute
271 K12
Dress and sports shirts,
dresses, pyjamas, skirts
and other garments
Straight
purl or
whip
stitch
1/2 inch to 11/16 inch
(12.7 toj 7.5mm)
Supplied up to
1 inch (25.4mm)
Elongated
bar
3/8 inch to 1 inch
(9.5 to 25.4mm)
in steps of
1/16 inch (1.6mm)
2.700
stitches per
minute
271 K13 Dress and sports shirts,
dresses, pyjamas, skirts
and other garments
Straight
purl or
whip
stitch
3/4 inch to 1-1 /2 inch Square or
(19 to 38mm) wide bar
3/4 inch to 1 -1/2 inch
(19 to 38mm)
in steps of
1/16 inch (1.6mm)
3.000
stitches per
minute
271 K14
Knit goods,
linen or cotton
garments
Whip
stitch
top cord
3/8 inch to 3/4 inch
(9.5 to 19mm)
Supplied up to
1 -1 /4 inch (32mm)
Square
bar.
Taper bar
at ifinish
3/8 inch to 1 -1/4 inch
(9.5 to 32mm)
in steps of
1/16 inch (1.6mm)
2.700
stitch es per
minute
•1/4 inch 2,700
bar. (9.5 to 32mm) stitches per
Taper bar in steps of minute
at finish 1/16 inch (1.6mm)
linen or cotton
garments
stitch
top cord
Button
hole
sewn
'twice
around"
(9.5 to 19mm)
Supplied up to
1 -1/4 inch (32mm)
271 K211 For installation on
Automatic Sequential
Electro-mechanical
Device 257464
Straight
purl or
whip
stitch
3/8 inch to 3/4 inch
(9.5 to 19mm)
Supplied up to
1 inch (25.4mm)
Square or
wide bar
3/8 inch to 1 inch
(9.5 to 25.4mm)
in steps of
1/16 inch (1.6mm)
2.700
stitches per
minute
271 KX1 Dress and sports shirts.
dresses, pyjamas, skirts
and other garments
Straight
purl or
whip
stitch
1/2 inch to 1 inch
(12.7 to 25.4mm)
Eyelet and
square bar
at finish
3/8 inch to 1 inch
(9.5 to 25.4mm)
in steps of
1/16 inch (1.6mm)
2.700
stitches per
minute
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Installation and Operation
This section of the manual contains general
information
for installing and operating 271 K machines.
Index
Page
Belt 6
Buttonhole length
6
Cleaning
6
Completing unfinished buttonhole 6
Gear identification 6
Gear changing 8
Internal oil passage alignment
6
Lubrication 12
Machine pulley
12
Needles and needle setting
12
Oil flow to hook regulation
12
Speed
12
Stitching over twice on the same buttonhole
12
Thread
12
Threading
14
Thread tensions
18
Two speed belt shifter
18
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Belt
Use only machine driving belt (endless) 271797, as
supplied with machine.
Do not overtighten.
With correct pulley for required speed fitted to motor,
adjust mo'or h)ight only to position where driving speed
is reached without belt slip.
Buttonhole Length Fig, a
Gauge Omarked in numbers corresponding to the
lengths of buttonholes which can be made.
Toadjust length of buttonhole:
1. Remove oil guard ®.
2. Place gauge Q on slide.
3. Loosen nuton regulator lever 0.
4. Align desired length of buttonhole marked on gauge
with line Q cut in slideway.
5. Move lever 0 until sleeve under nut rests against
downward projection of gauge.
6.
Tighten nut 0.
7. Replace oil guard 0.
Cleaning
Use only a short bristled brush to remove lint or waste
from around the sewing hook, knife, work clamp and
moving parts on underside of needle plate.
Wipe off any excess oil on machine surfaces, particularly
areas which may contact material to be sewn.
Completing an Unfinished Button-
hole after Rethreading Figs. B.C.
1. Pull forward, repeatedly, ratchet lever 0 until the
unfinished buttonhole is in the correct position to
resumesewing.
2. Pull out lever 0 for half speed operation.
3. Start machine.
Identification-Feed Wheel Gears
Beneath Machine Bed Fig, d
Feed wheel gear 0.
Feed wheel driving shaft Q.
Intermediate gear ®.
Feed wheel driving shaft gear 0.
identification-Gear Train at
'Stop' Position fiq e
Stitch regulating gear driving 0.
Stitch regulating gear driven ®.
Hook driving connection belt pulley gear ®.
Feed driving gear ®.
Feed driving bevel pinion ®.
Feed driving bevel gear 0.
Eccentric studs 0.
Feed driving pinion ©.
Feed ratchet gear upper 0.
Feed ratchet gear lower 0.
Needle bar frame driving gear 0.
internal Oil Passage
Alignment Fig, f
1. Position stamped mark 0 on bobbin case opener
brackethingestud 0, at sixo'clock.
2. Position stamped mark 0 on front hook shaft bushing,
at six o'clock.
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Fig. E
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Gear Selection Chart
STITCH REGULATING GEARS
NUMBER OF STITCHES (Needle Dips)
OBTAINED IN BUTTONHOLE FOR EACH
REVOLUTION OF FEED WHEEL
USED AS
USED AS
USING FEED-DRIVING
USING FEED-DRIVING
DRIVEN
DRIVING
GEAR 271550 (64 teeth)
GEAR 271854 (72 teeth)
GEAR GEAR
WITH UPPER FEED
RATCHET GEAR 271559
(32 teeth)
WITH UPPER FEED
RATCHET GEAR 271855
(24 teeth)
PART
Number PART
Number MEDIUM RANGE
FINE RANGE
NUMBER of NUMBER
of
(Regularly supplied in
(Regularly supplied in
Teeth
Teeth Machines 271 K11, 271KX1,
271 K14, 271K24and 271K211)
Machines 271K12 and
271 K13)
271646 60
271634 30
240
360
271648 60 271637
36
200
300
271645 54 271636
36
180
270
271642
48 271638 36
160
240
1271644
50 t271639 40 150
—
271643©
48 271640© 40 144
216©
*271459 44 ♦271458
40 132
198
271641©
45 271641© 45
120© 180
271640© 40
271643© 48
100©
150
271639© 40
271644© 50 96
144©
t271638 36 t271642
48 90
—
271636
36 271645 54
80 120
271637 36
271648 60 72
108
*271635 32 *271647
60 64 96
271634 30 271646
60 60 90
•NOT REVERSIBLE: Reversing this set of gears may
cause needle to stop at odd intervals.
tThese gears can be used in locations listed, only when
machine is fitted with medium range Feed Driving Gear
271550 and Feed Ratchet Gear 271559.
©Regular for machines 271K11, 271KX1 and 271K211
giving six barring stitches.
©Regular for machine 271K12 (NOT REVERSIBLE)
giving eight barring stitches.
©Regular for machine 271 K13, giving five barring stitches.
©Regular for machines 271 K14 and 271K24. giving four
barring stitches.
See instructions on page 10 for method of changing these
gears.
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Buttonhole—Number of Stitches
The number of stitches in a buttonhole is controlled by
the set of stitch regulating gears selected for use.
instruction for Marking
Stitch Regulating Gears Figs. A.B.
Caution: It is very important that the machine be
properly timed for correct cycling before being
used for marking the stitch regulating gears.
1. Select set of stitch regulating gears (2 gears) for
desired number of stitches using gear selection chart.
(see page8).
2. Set starting lever in running position.
3. Turn arm shaft in normal direction of rotation to
position point of needle approximately even with top
of the clamp check with needle bar rising on the right
hand side (maintain this position).
4. Remove the two stitch regulating gears from the
machine.
5. Select the stitch regulating gear to be (driven) from
the new set and position on to the feed wheel driving
shaft, making sure that the lug on the feed wheel
driving shaft is seated into the slot of the stitch
regulating gear.
6. Using the (driven) stitch regulating gear Q. turn the
feed wheel driving shaft O' clockwise until the back
barring plate is past the barring point, then reverse the
rotation of the feed wheel driving shaft counter
clockwise to position back edge of barring plate flush
against barring point (trip barring trip lever before
reversing direction of the feed wheel driving shaft).
T. While maintaining the position of the barring plate
flush against the barring point by holding the tripping
point disc located on the feed wheel shaft, position
the (driving) stitch regulating gear ^ on to the feed
driving gear stud 0meshing the teeth of the (driving)
stitch regulating gear O with teeth of the (driven)
stitch regulating gear 0, and seat slot of (driving)
stitch regulating gear on to lug of feed driving gear if
alignment of slot and lug permits.
8. If the slot in the (driving) stitch regulating gear does
not line up with lug of feed driving gear when teeth
of both stitch regulating gears are meshed, select the
gear tooth mesh that will position the slot in the
(driving) stitch regulating gear as close to meshing as
possible past the lug on feed driving gear in the
direction of rotation (counterclockwise) never to
exceed one full tooth. (See fig. A).
10. Ratchet machine close to stop position and rotate arm
shaft to set machine into stop position and mark the
two stitch regulating gears as shown in fig. B.
(Note: The related markings on any set of stitch
regulating gears are good only in the machine in which
the gears were originally marked).
Note: It is absolutely necessary to use some type of code
when marking the stitch regulating gears to insure proper
location and tooth mesh
when re-assembling amarked set
of gears into a machine (see fig. B). It should also be noted
that changing the ratio of stitch gears may cause machine
to stop on either left or right side. This condition is not
objectionable or detrimental to sewing.
Installing Pre-marked
Stitch Regulating Gears Figs. A.B.
1. Run machine into stop position.
2. Remove previously used stitch regulating gears from
machines.
3. Position (driven) stitch regulating gear 0 from new
set on to feed wheel driving shaft "B" O (fig. B)
aligning and seating slot let (driven) gear on to lug of
shaft.
4. Position (driving) stitch regulating gear O from new set
on to feed driving gear stud "A" 0 (fig. B) meshing
teeth of (driving) gear with teeth of (driven) gear with
"A" mark on (driving) gear aligned with "B" mark on
(driven) gear.
5. Turn (driving) stitch regulating gear counterclockwise
until slot in (driving) gear aligns and seats on to lug of
feed driving gear making sure that the (driven) stitch
regulating gear re .iains seated and engaged on lug of
feed wheel driving shaft and teeth of both stitch
regulating gears stay meshed.
Note that for a finer range of stitching, upper feed ratchet
gear and feed driving gear may also require changing.
To Change Upper Feed
Ratchet Gear Figs. C.D.
Remove cap-screw
washer Q.
2. Lift out gear.
0, retainer 0, spring 0 and
Select correct upper feed ratchet gear from chart on
page 8 and place on its shaft.
Replace washer
screw 0.
0, spring 0. retainer 0 and cap-
Caution: Never change the pre-set position of To Change Feed Driving Gear
the (driven) stitch regulating gear 0 to facili
tate the meshing of the slot and lug.
Rotate arm shaft in normal direction of rotation until
lug on feed driving gear 0 engages and seats into slot
in (driving) stitch regulating gear.
1. Loosen eccentric stud socket screw
2. Remove eccentric stud ^
3. Slide out feed driving gear 0.
4. Replace with selected gear.
5. Replace eccentric stud 0.
6. Tighten socket screw 0.
Note: It may be necessary to adjust feed wheel stop
position and cord finger latching after a change of stitch
regulating gears.
10
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Fig. A
Correct
Incorrect
O o
Fig.B
11
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Lubrication Figs. A.B.
Use Singer OiFType 'A' or 'C.
Use type 'C to minimise stain on fabrics.
Do not use additives to machine oil.
1. Fill the oil reservoir through hole Q to the high mark
O on the gauge Q.
2. Oil level must notbe allowed to fall belowlow mark Q.
3. When machine is new or has been idle for some time
apply oil to initial lubricating points 0.
4. Apply oil daily to oiling points 0.
5. Do not apply more than one drop of oil to Q.
6. Saturate felt Q daily.
7. Apply oil freely to holes marked by red doL
Machine Pulley
Machine pulley (loose double-shielded bearing) with belt
groove diameter 2-3/4 inches (70mm) for machine driving
belt (endless) 271707.
Machine pulley (tight) 271617 drives machine at half
operating speed.
These pulleys are fitted with permanently lubricated,
sealed ball bearings.
Machine pulley (positive drive) drives machine, through
gear train, at operating speed.
Direction of rotation of pulleys is to
the left, anti-clockwise
from the operator's position.
Needles and Needle Setting Fig, c
Use only Singer Needles, Catalogue 1526.
Needle size selection is determined by the particular
machine, thread and material in use and the type of
buttonhole to be sewn, purl or whipstitch.
Generally, the smallest size of needle which allows the
thread in use to pass freely through the needle eye, should
be used.
Use the smallest possible needle for the thread in use.
Correct needle selection makes a great difference in the
ease and quality of the work.
To set:
' 1. Loosen screwQ In lower end of needle bar.
2. Insert needle into needle bar as far as possible ©.
Long groove of needle Q toward rear, facing knife.
Needle eye directly in line with machine arm.
3. Tighten screw 0.
OilFlow to Hook—Regulation Fig, d
1. Run machine for approximately one minute.
2. Stop machine and hold a piece of paper under hook.
3. Run machine for five buttonhole cycles. Correct
pattern will show five oil stains on paper.
4^ If oil pattern is incorrect turn screw 0 until it is
1/8 inch (3.2mm) out of the bracket face.
5^ Run at least fifteen buttonhole cycles and recheck
pattern on paper.
6. Re-adjust if necessary turning clockwise to increase
flow and anti-clockwise to decrease flow, until
pattern is correct.
Do not alter the setting of screw located at back centre of
hook base which is an oil metering screw with a set
aperture.
Speed
Maximum recommended speeds are given In 'Special
Features of Machine Varieties' on page 4.
Optimum speed for efficient operation is determined by
the material, thread and buttonhole style to be sewn.
New machines should be run at speeds 500 stitches per
minute less than the recommended maximum, for the first
hundred hours.
Stitching Over Twice on the same
Buttonhole (Machines 271K14) Fig. E
To Stitch over a buttonhole twice, for added strength or
aay other reason.
1. Press down knife bar disengaging lever stud 0 until
first cycle is complete.
2. Release knife bar disengaging lever stud 0before
commencing second cycle.
Thread
Needle thread: Left or right twist.
Where the application demands maximum or near maximum
needle bar throw (bight), right twist thread is recom
mended.
Bobbin thread: Left or right twist.
For whipstitch, thread sizes should be the same for needle
and bobbin, e.g. 50/3.
For purl stitch, the needle thread should be larger than the
bobbin thread, e.g. 40/6 needle thread and 90/3 bobbin
thread.
12
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o
o
m
Q
0 Decrease
Increase
13
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Threading
Needle Thread Fg a
1. Pass thread from unwinder O down through thread
tension guide.on top of arm Q.
2. Lead thread through threading points shown.
3. Pass thread from rear to front through needle eye Q.
4. Draw about two inches of thread through needle eye
to start the stitching Q.
Whipstitch Buttonhole Fig, a
By-pass middle tension device 0 on machine arm.
On machines designed primarily for whipstitch buttonholes,
such as machine 271 K14 and 271 K24 this middle tension
device 0 has been omitted.
Top Cord (271K14 and 271K24) Fig. 8
1. Pass the cord from unwinder Ointo wire guide 0 on
right side of machine head.
2. Lead cord through threading points shown and
behind cording mechanism.
3. Draw about one inch of cord down through hole in
end of cord finger O to start the stitching.
14
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Fig. A
15
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, Bobbin Removal Rg. a
i fteSih bene^h machine bed and with thumb and fore-
! finger of lefj/njand remove bobbin case cap and bobbin as
! follows:
11.gpen latcb O.
i :H:ptddiStett and pull case from sewing hook 0.
j3. Relea^ latch 0.
; 4. Remove bobbin from bobbin case O. When latch is
i held open, bobbin is retained in bobbin case.
1 Bobbin Winding Fig, b
! 1. . Thread the tension control 0.
f lace bobbinon spindle0 as far as possible.
13. Wind thread around bobbin Q.
!4. Push lever 0 in. to bring pulley In contact with belt.
If necessary, loosen screws 0, adjust for even winding and
itighten screws 0. Apply a drop of oil to points 0.
The bobbin winder stops automatically when sufficient
thread has been wound on bobbin.
Threading and Replacing
Bobbin Case Figs. C.D.
1.1 Hold the bobbin case with slot0 near top.
2. Replace bobbin in bobbin case 0.
3. Pull thread into lower slot 0.
4. Draw thread up under spring 0.
5. Grasploop of thread above spring 0.
6. Pull thread into middle slot"^
7. Drawthread up and slip into upper slot
8. Release loop of thread 0.
9. Draw thread taut between upper, middle and lower
slots 0.
10. Replace bobbin case on stud @.
11. Release latch 0.
12. Press back until latch catches groove in stud.
Draw about 1-1/2 inches of thread from bobbin to
start the stitching. Donot exceed this length or thread
may be trapped between hook and base.
16
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o
Fig .C
fj lf^\
rlfnl
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1
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Txil ®
J
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17
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Thread Tensions Fig.
Tension on threads should be as light as possible while
still sufficient to set stitches correctly in buttonhole.
Needle thread tension is regulated by thumb nuts Q. O
and O-
Needle Thread Take-up Spring Fig, b
Tension on the take-up spring 0 should be sufficient to
control thread during downward stroke of the needle.
To set:
1. Turn tension stud 0 clockwise to decrease, anti-
clockwise to increase tension.
The height of the spring should be set to control the thread
until eye of needle reaches material.
To adjust:
1. Loosen set screw 0.
Turn tension only. Clockwise to decrease, anti
clockwise to increase.
3. Tighten set screw 0.
Bobbin Thread Tension Fig a
Bobbin thread tension is regulated by screw Q.
Bobbin thread tension is approximately correct when, the
bobbin unwinds by its own weight if suspended by its
thread.
Side of Arm Tension
Fig. A
Tension should be as light as possible but stillsufficient to
ensure well balanced stitches on the bars in conjunction
with the bobbin case tension.
To adjust:
1. Turn thumb nut O clockwise to increase, anti
clockwise to decrease.
Top of Arm Tension Fig, a
Tension should be set to give a purl stitch on the leg and
should be just sufficient to drawthe purl evenlyto top side
of buttonhole.
To adjust: ,,
1. Turn thumb nut 0 clockwise
clockwise to decrease.
to increase, anti-
Pre-tension Controi
Fig. C
Tension on needle thread from pre-tension control should
be just enough to prevent sewing hook from stealing the
thread at the end of the first bar.
Toadjust:
1. Turn thumb nut 0 until even the first three or four
stitches, immediately following the bar stitches, pull
up into an attractive purl stitch.
T. Correct tension shown at 0. '
Incorrect tension shown at 0.
Whipstitch
Thread should not be passed through middle tension
device.
Two-speed Beit Shifter Fig, o
Atwo-speed belt shifter permits operation of the machine
at half normalspeed when required.
To operate at half speed, pull out lever 0.
To return to normal speed, push in lever 0.
18
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LD
More tension
Less tension
Fig.C
O
Fig.D
II -Ir
19
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Timing and Setting
All machines are correctly timed and set before leaving the
factory.
Iffor any reason setting or timing has been disturbed, it is
necessary to readjust as given in the following section.
index Page
Automatic knife bar disengaging lever
22
Barring
22
Barring tension plate actuator
24
Belt shifter
24
Bight width
26
Bobbin case stop. Horizontal position
26
Bobbin case stop. Vertical position
26
Clamp check centralising
26
Clamp check clearance with needle
26
Cutting space
28
Driving lever spring tension 28
Feed wheel tripping points
28
Interlocking rod guide and lock pin clearance 30
Interlocking rod tension 30
Knife bar height
30
Knife holder guide stud location 30
Knife slot in needle plate alignment
32
Latch tripping plate
32
Needle and knife alignment
32
Needle bar frame height
32
Needle bar frame play
32
Needle bar height
32
Needle plate centralising
32
Safety devices
34
Safety tripping lock
34
Sewing hook
34
Sewing hook setting
34
Sewing hook timing
34
Sewing safety lock
34
Starting lever rod
34
Stop cam face and interlocking rod clearance
34
Stop cam gear and pinion play
36
Stop motion
36
Tension releaser (top of arm)
36
Thread breaking or fraying—elimination
36
Top cord finger
38
Upper thread cutting and clamping blades
40
21
From the library of: Superior Sewing Machine & Supply LLC

Automatic Knife Bar Disengaging
Lever Fig, a
When sewing at full speed this lever O should be slightly
above pin O and will have little or no vertical motion.
To adjust:
1• Loosen set screw 0.
2. Move balance weight O forward or backward along
the lever Q until the lever rests lightly on the pin Q.
3. Tighten set screw Q.
4. Set thread guide height so that when sewing the lever
will just clear pin.
Barring Fig b
The barring shaft assembly must be positioned with its
slide 0 in line with the needle bar frame connection 0
when the needle bar is at its lowest point.
271K24 Machines
Carry out the same setting procedure as detailed but on
the second time round.
Barring Trip Lever Figs. D.E.
This lever 0 should retain barring slide 0 in position
shown in Fig. E. until the needle, on its upward stroke, has
cleared clamp check.
Toadjust:
T. Ratchet the machine until barring plate 0 is under
barring point 0.
2. Loosen the two screws 0.
3. Adjust trip lever 0 to fall into notch in barring slide
4. Tighten screws 0.
5.
Check for correct latching action when barring point
rides on the other barring plate.
Barring Stitches in the Bar Figs, c d. Barring Tripping Point Fig, f
The barring tripping point 0 should cause trip lever 0 to
release barring slide when trip lever strikes the tripping
point.
To adjust:
The number of stitches in the bars is related to the total
number of stitches in the buttonhole and can only be
altered by changing the stitch regulating gears selected
for use. See page 10.
To check the numberof stitches in the bars:
1. Open up cutting space to maximum.
2. Ratchet machine on to left hand side of buttonhole. 1°'^ P°'"'Posf'O" while re-tightening screw
3. Draw a pencil line acrossgiband slide.
4. Ratchet machine on to bar.
5. Draw a pencil lineacross gib and slide.
6. Ratchet machine on to right hand side of buttonhole.
7. Draw a pencil line across gib and slide.
8. Ratchet machine on to left hand side of buttonhole.
9. Set machine in run position.
10. Note the pencil line across gib and slide indicating the
left hand side of buttonhole.
11. Turn the machine over by hand until the line breaks
and the pencil lines marked on the slide and gib,
indicating the top bar, just align.
12. Continue to turn the machine over by hand and count
the number of needle bar dips until the pencil lines
indicating the top bar just break.
The number of needle bar dips counted will be the number
of stitches in the bar.
Barring Stitch Setting Figs. B.D.
The desired setting of barring stitches is achieved when
the barrin^^plates O are correctly located on cam 0.
To check,?
1. Carry out the procedure 1. to 11. detailed above.
2. Continue to turn the machine over by hand until the
pencil lines indicating the top bar just break.
At this point the needle should be rising on its right hand
throw and the point of the needle just clear of the clamp
check.
If the needle is found to be on the left hand throw then:
1. Loosen screw 0.
2^ Move point as required.
®
4! Do not allow tripping point to depress trip lever any
more than is necessary to release the barring slide.
57" Recheck for excessive play. 1/64 inch (0.4mm)
maximum, of barring slide and adjust the stop screw
0 when necessary.
Barring Stitch Width Figs. B.C.D.E.
The width of barring stitches is controlled by the height of
barring point 0.
A slight adjustment of barring point will change width of
barring stitches considerably.
Toset approximately:
1. Loosen screw
2. Insert a 0.015 inch (0.4mm) shim 0 between barring
point 0 and top surface of cam 0.
3. Drop barring point on top of shim.
4.
Tighten screw 0.
To increase width:
1. Ratchet the barring plate cam 0 until the barring
point 0 rides on top offirst barriTig plate Q on the cam.
2. Back out stop screw 0.
3. Loosen barring pointscrew 0.
4. Lower barring point as required.
5. Tighten barring point screw 0.
6. Turn in stop screw 0 until there is 1 /64 inch (0.4mm)
maximum play in barring slide 0.
7. Turn in set screw 0 against end of stop screw.
To decrease width:
1. Remove the stitch regulating driving gear.
1.
Ratchet the barring plate cam 0 until the barring
2. Turn the machine over until the needle is in the
point 0 rides on top of barring plate ©.
desired position.
2.
Loosen barring point screw 0.
3. Replace stitch regulating driving gear as instructed on
page 10.
3. Raise barring point as required.
4.
Tighten barring point screw 0.
When the machine is in this setting the first barring point
should have just tripped-off the barring plate.
To adjust:
5.
Back out set screw 0.
6.
Turn in stop screw 0 until there is 1/64 inch (0.4mm)
maximum play in barring slide. .
1. Loosen screw 0.
7. Turn in set screw © against end of stop screw 0.
2. Move plate © flush against back of barring point 0.
3. vTighten screw 0.
Set the other barrina olate In thp .<;amn wav/ hut at tho lact
8.
Check for excessive play or binding while barring
point rides over the other barring plate on cam.
stitch in the second bar.
Recheck settings.
22
From the library of: Superior Sewing Machine & Supply LLC