Singer 321C 131M-04 User manual

High
Speed
Overlock
Machine
73 7 M—04 243M—24 / TF
732M—075 244 M—24
733M—04 /TF 257 M—35
734M—04 257 M—55
24 7 M—24 / 25 257 H—56
® Singer is a registered trademark of The Singer Company Limited or its affiliated companies.
© 2009 Copyright The Singer Company Limited

1.1 Important Safety Instructions 1
1.2 Safe Operation 2
2.1 Product Description 3
2.2 Machine Specification 4
2.3 Motor, Motor Pulley and Belt 4
3.1 Table Cut-Out Diagram 5
3.2 Machine Installation 6
3.3 Lubrification and Oil Drainage 8
9
9
3.4 Needle Attachment (or Replacement)
3.5 MachineThreading
3.6 Thread Tension Adjustment 10
3.6.1 Tension Nut Adjustment 10
3.6.2 NeedleThread Control 10
3.6.3 LooperThread Control 11
3.6.4 Chain LooperThread Cam Control 11
3.7 Adjusting the Differential Feed Rate 12
3.8 Stitch Length Adjustment 12
3.9 Parts Relation andTiming 13
3.9.1 Needle and Needle Plate 13
3.9.2 Upper Looper (Spreader) and Needle 14
3.9.3 Lower Looper and Needle 14
3.9.4 Upper and Lower Loopers 15
3.9.5 Needle and Needle Guard 15
3.9.6 Chain Looper and Needle 15
—
4.1 Machine Head Cleaning 16
4.2 Oil Change and Filter Cleaning 16
4.3 Safety Inspection 16

6.1 Frame Components 20
6.2 Cloth Plate Components 22
6.3 Cover Components 24
6.4 Main Shaft Components 26
6.5 Needle Bar Components 28
6.6 Thread Guide Components 30
6.7 Upper Looper Components 32
6.8 Lower Looper Components 34
6.9 Front Looper Components 35
6.10 Cam Components 36
6.11 Differential Feed Components 38
6.12 Feed Dog Components 40
6.13 Trimming Components 42
6.14 Presser Foot Components 44
6.15 Lubrication Components 46
6.16 Feed Snap Components 48
6.17 Thread Spool Components 50
6.18 Plate Row Material Components 52
6.19 Accessories 53

1.1
Important Safety
Instructions
Important
When using the
machine, basic
safety procedures
must be followed.
Flead with attention
all instructions before
using the machine.
When using it,
understand that
all basic safety
instructions are
not limited to the
following items.
Read all instructions,
take care of this
manual, and use it
as reference when
necessary.
Safety Instructions
0 Before running the machine, make
sure all relevant safety specifica-
tions are adequate to specifica-
tions and technical standards in
your country.
0The machine should not be run
without its safety devices.
0 The machine should only be oper-
ated by properly trained personnel.
0 For your safety, goggles must be
used While running the machine.
0 Turn off or unplug the machine in
the following situations:
0 Passing the thread by the nee-
dle or replacing the bobbin or
looper.
0 Replacing the needle, presser
foot, throat plate, feed dog and
sliding plate.
0 When the machine is in main-
tenance.
0 When the operator is not run-
ning the machine.
Oln case of lubricant oil contact
with the eyes or skin, wash the
surface with plenty of icy water.
In case of ingestion, seek medical
help immediately.
ORepair, fitting or maintenance
should only be performed by
properly trained personnel.
0Maintenance and repair on elec-
tric equipment should only be
made by qualified personnel. If
any electric device is damaged,
the machine should be immedi-
ately stopped.
0 Before starting the machine in full
running, a test must be conducted
to assure that machine and opera-
tor are able to perform the task.
0 The machine should not be placed
next to a sound source as an ultra-
sonic welding machine and other
equipment.
0 The machine should only be run
with the proper electric cable
and connectors, and also the ad-
equate grounding.
. The machine should only be used
to sew materials as indicated in
its instructions manual, and indi-
cations of use should be followed.
Singer will not be held responsible
for any damage caused by unau-
thorized changes in the product.
High Speed Overlook Machine | Instructions Manual and Parts List 1

1.2
Safe Operation
A0 To avoid the risk of electric shock,
do not open the motor wiring box
and do not touch the components
assembled inside the wiring box.
0To avoid injuries do not run the
machine without the belt cover or
in case any other safety device is
removed.
0To avoid possible injuries keep
fingers, head, and clothes far
from wheel, belt and motor when
the machine is running. Nothing
should be placed near those parts.
0To avoid injuries never put your
0To avoid accidents in case of a
sudden start of the machine al-
ways turn it off when laying it
down, or remove the belt cover
and the belt.
Olf your machine is equipped with
a servomotor, it does not make
noises while being driven. To avoid
a possible accident caused by an
unexpected start, bev sure the ma-
chine is turned off.
0To avoid electric, do not run the
machine without proper ground-
Ing.
fingers next to the loopers when A'TO minimize the risk of accidents
the machine is running.
0The shuttle whirls at high speed
while the machine is running. To
avoid hand injuries, keep them
away from the shuttle while the
machine is running. Turn off the
machine to replace the bobbin.
0 To avoid possible injuries be care-
ful when putting down or lifting
the machine head.
or damages in electric compo-
nents caused by electric discharge
turn the machine off before un-
plugging it.
OCIean the machine periodically.
High Speed Overlook Machine | Instructions Manual and Parts List 2

2 1 High Speed Overlock Machine
I
Product
Description
High Speed Overlock Machine | Instructions Manual and Parts List 3

2.2
Machine
Specification
9"
o
.0"
o
.0"
o
N
I
0
Clutch
motor
1/2
HP
(400W)
high
2
3
Speed
(2
poles)
l
Motor,
Motor
'
Belt
type
M
Pulley
and
Belt
90
i
95
i
100
i
105
i
110
i
115
High Speed Overlock Machine | Instructions Manual and Parts List 4

3.1
Table Cut-Out
Diagram
65]—
214 V
259 J—
305 J—
442 L
540 V
4001—
—
433
A
300
A
269 258
Figure 1
289
359
469
537
595
1200
High Speed Overlock Machine | Instructions Manual and Parts List
(2)13
¢27

3 2 Install the machine support compo- the needle bed surface to the table
I
nents and the residues cam as indi- top is 100mm. For inserted assem-
_ cated on figure 2. In case ofsemi-in- bly the distance is about 5.0mm.
maChme serted assembly the distance from
Installation
Figure 2
High Speed Overlook Machine | Instructions Manual and Parts List 6

port base. the right side and the pedal of the
3 2 Set the machine head on the sup- Install the friction motor pedal at
I
presser
lifter
at
the
left
side.
- Connect the machine Wheel to the
maChlne motor With the belt. Be sure the motor is clockwise di-
Installation -
Adjust
the
belt
tension
so
that
there
rected,
referred
to
figure
3'
is a gap of about 20 mm when the
center of belt is pressured.
Set the belt cover according to fig-
ure 4.
Figure4
High Speed Overlook Machine | Instructions Manual and Parts List 7

3.3
Lubrication
and Oil
Drainage
Important
As this is a high
speed machine,
DO NOT run the
machine before
oiling and assuring
the direction of
motor rotation.
Remove the oil flow sight win-
dow 14’ and fill with the lubricant
oil (Singer Oil), until the indicator
of the oil level is between the two
lines of the oil level sight window
’3’. After that, put back the oil flow
window ’A’ and squeeze it.
When using the machine for the
first time, or a machine that has
not been used for some time, oil
the needle bar top, the guides and
loopers before running it.
A new machine should be run at
80% maximum speed on the first
four weeks. After this initial cycle,
Figure 5
replace the oil and from then on
the machine can be used at maxi-
mum speed.
To preserve the machine, change
the oil after four weeks of use. After
that the oil must be changed every
four months. To change the oil sim-
ply remove the screw ’0’ indicated
on figure 6. After draining the oil,
replace the screw and complete the
machine with new oil.
This machine has an oil filter (fig-
ure 6) that must be cleaned every
month or changed as needed.
High Speed Overlook Machine | Instructions Manual and Parts List 8

Use
needle
Singer
6120-06.
|—
—|
3.
4
Release
screw
’1’
as
indicated
on
W
Needle figure 7 and put (or Withdraw the _
old needle).
AflaChment I It th dl 'th th I tt d nse e nee e WI e s o urne
(or Replacement) to the back side and push it up until
the bar end. Tighten screw ’1.’
7
Figure 7
3 5 For five thread machine For three / four thread machine
I
Machine
Threading
Important
Refer to the sewing
type you need for
correct threading. Any
incorrect threading
may cause thread
brake, uneven
stitches or skip
stitches.
High Speed Overlook Machine | Instructions Manual and Parts List 9

3.6
Thread Tension
Adjustment
Important
The thread tension should be adjusted according to the type and thickness of
cloth, thread, sewing Width, stitch length and others. Therefore, the pressure on
the Tension Buttons or Thread Guides should be individually adjusted for each case.
3.6.
1
Tension Nut
Adjustment
3.6.2
Needle
Thread Control
Note
The signal (+)
increases the tension
in the thread. The
signal (-) reduces the
tension of the thread.
Tension Nut 3: controls the thread
in the right looper
The following adjustments are re-
lated to figure 10.
Tension Nut 4: controls the thread
in the left looper
Tension Nut 1: controls the needle
thread or the left thread in case of
two need/es.
Tension Nut 5: controls the thread
of the safety stitch. Tension Nut 2: controls the thread
in the right needle.
\/
Figure 10
For all types ofstitch 504, 512 or 514,
move down the guides ’1’and ’2’.
For the types of stitch 503 and 505,
move the guides ’1’ and ’2’ to the
highest point.
High Speed Overlook Machine | Instructions Manual and Parts List 10

3.6.3
Looper
Thread Control
Note
The signal (+) means
more thread and (-l
means less thread.
3.6.4
Chain Looper
Thread Cam
Control
For the type ofstitch 512, when Ad- For the type of stitch 503 and 505,
just guide ’1’and ’2’as follows the move the guides to the lowest
looper on the right is at the left far point and adjust ’1’ and ’2’ in level
end, adjust ’1’ and ’2’ in level with with the continuous line.
the
dotted
mark,
as
on
figure
12.
Adjust
guide
,3,“
follows:
0 Position 14’: for stretchy thread
0 Position ’B’: for seaming and blind
stitch hemming
0 Position ’0’: stitch type 512
Adjust guide ’4’ as follows:
0 Position ’0’: for stretchy thread
0 Position ’E’: for seaming and blind
stitch hemming.
Figure 12
When the needle is on high posi-
tion, mark 14’ must be aligned with
the thread guide bracket ’1’, as
shown on figure 13.
Release screw ’2’ and the thread
cam ’3’. Turn it clockwise for quick
release of thread through the cam.
Figure 13
High Speed Overlook Machine | Instructions Manual and Parts List 11

3.7
Adjusting the
Differential
Feed Rate
Note
When the surface of
level ’3’adjustment
is on scale 2, the
differential adjustment
is l .' l, and if it is
on the scale, its
proportion may be
adjusted up to 7 .' 0.7
3.8
Stitch Length
Adjustment
Important
The stitch length
adjustment is
made according to
the sewing fabric,
differential feed ratio
and other factors.
Adjustment of the differential is the
dragging proportion between the
main feed dog and differencial feed
dog. When the movement of main
feed dog is less than that of the
differencial feed dog, the cloth will
be frilled during sewing. Otherwise,
the cloth will be stretched.
Press button to the end and keep it
pressed as shown on figure 15.
Turn the wheel until we have the
desired stitch length. It is shown on
the wheel scale.
Release nut ’1’on figure 14, and turn
screw ’2’ clockwise to streching the
cloth or counter clockwise to shrink
it. Retightend the nut ’1’.
Figure 14
/
Figure 15
1. 0 1. 4 1. 7 2. 5
2.3 3.1 3.9 4.7 5.4 5.9
0.9 1.2 1.5 1.8 2.1 1.0
High Speed Overlock Machine | Instructions Manual and Parts List 12

3.9
Parts Relation
and Timing
3.9.
1
Needle and
Needle Plate
When needle at the highest posi-
tion, distance 14’ between needle
point (the left needle if there are
two needles) and needle plate is
9.5 to 9.7 mm for standard adjust-
ment, or 10.8 to 11.0 mm for spe-
cific cases. Each needle should be
centralized over each hole in the
needle plate. The right needle must
be about 0.2 to 0.3 mm ahead the
left needle.
Distance between needle point ( the
right needle if there are two nee-
dles) and the front part of the hole
in the needle plate or presser foot
is 1.2 mm.
A:
9,5
-
9,7
mm
High
Lift:
10,8
-
11,0
mm
Release screw ’1: as shown on fig-
ure 16.
Turn the wheel to see if needle is
centralized at every hole of the
needle plate. Release screw ’2’ to
adjust needle holder.
Turn the wheel to move needle to
the highest position and move nee-
dle bar until the height is correctly
adjusted.
Tighten screws ’1’and ’2’.
Figure 16
High Speed Overlook Machine | Instructions Manual and Parts List 13

3.9.2
Upper Looper
(Spreader)
and Needle
3.9.3
Lower Looper
and Needle
When the right looper moves to the needle. For two needles, the dis-
far left end, distance fl’between the tance ’B’ is 5.5 to 6.0 mm from the
looper point and the center line of left need/e, as shown on figure 12
the needle is 4.5 to 5.0 mm for one
Figure 17
When
the
lower
looper
moves
to
When
the
lower
looper
moves
to
the
extremly
left,
the
distance
14’
the
center
line
of
needle
(left
nee-
between
looper
point
and
center
die,
if
two
needles),
the
gap
be-
line
of
the
needle
(left
needle,
if
tween
needle
and
looper
is
from
0
two
needles)
is
from
3.4
to
3.6
mm,
to
0.05
mm,
as
shown
on
figure
19.
for high lift machines, as shown on
figure
18. E
E
(m
0
©
”8’
:i;—:
i—f_
Figure 19
A
Figure 18
High Speed Overlook Machine | Instructions Manual and Parts List 14

3.9.4
Upper and
Lower Loopers
3.9.5
Needle and
Needle Guard
3.9.6
Chain Looper
and Needle
When the upper and lower Ioopers
are crossed, the distance is 0.2 mm
for ’A’ and 0.5 mm for ’B’, accord-
ing figure 20.
When the looper point is on the
side opposite to the center line of
the needle (left needle if there are
two needles), space between nee-
dle and rear needle guard of 14’ is
0 mm. When needle moves to the
lowest position, space between
needle and front needle guard of
’B’is from 0.15 to 0.20 mm, accord-
ing to figure 21.
The safety looper should be fixed in
a position lower than this support.
And when it moves to the left far
end, the distance between the loop-
er point and the center line ofneedle
is 2.5 mm, according to figure 22.
0.5
A
0.2
. //
__ /
/_'\_
Figure 20
0.0
A
0.15 - 0.20 mm
In!“
M?
Figure 21
Figure 22
High Speed Overlook Machine | Instructions Manual and Parts List
15

E
4.1
Machine
Head Cleaning
4.2
Oil Change and
Filter Cleaning
4.3
Safety
Inspection
Maintenance
Clean the machine head periodi-
cally with a dry soft cloth to remove
the excess of dust in the head. Do
not use any kind of solvent material
to clean the surface.
If the machine has not been used for
a long time, lubricate the superior
part of the needle bar, guides and
loopers before returning to opera-
tion.
Oil should be changed every four
months. When changing the oil fol-
low instructions on item 3.3.
Frequently check if all safety de-
vices are properly installed and
adjusted.
Check all screws that fix and hold
the machine head that should be
properly tight.
Check and be sure the belt is not
excessively worn out and see that
it has the proper tension.
Oil filter should be cleaned every
month or replaced for a new one
as necessary. To clean the filter or
change the oil, fol/ow instruction in
item 3.3.
Check and be sure there is no mo-
tor overheating and be sure that
the cable and electric connector
are not damaged.
High Speed Overlook Machine | Instructions Manual and Parts List 16

Possible Causes
H
Needle installed the wrong way.
Wrong kind of needle.
Damaged needle.
Wrong relation with needle guards.
Wrong relation with looper.
939199!“
plate or the presser foot.
Needle is not centralized with the hole at the needle
H
Low quality thread.
Thread is thicker than the eye of the needle.
Wrong passage of thread.
Thread tension too tight.
Needle wrongly set.
915-"!in
Thread stand wrongly set.
Z
Needle
overheating.
8. Tension disk or guides with burrs .
9. Wrong relation of needle with looper.
10.
Needle,
looper,
needle
plate
and
guides
have
burrs.
1.
Wrong
relation
of
needle
with
looper.
.
Wrong
passage
of
thread.
. Inadequate tension of thread.
2
3. Needle installed the wrong way.
4
5 . Point of looper damaged.
6.
Needle
damaged.
Z Wrong installation of needle guards.
1. Wrong threading.
2. Thread is thicker than needle hole.
3. Wrong thread tension.
4.
Needle
thread
is
not
lubricated.
5.
Wrong
relation
of
needle
with
looper.
High Speed Overlock Machine | Instructions Manual and Parts List
1 \l