Pfaff 436 User manual

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PFAFF 436
One Needle Locksfifch Superspeed Sewer
with Automatic Lubrication
INSTRUCTION BOOK
G. M. PFAFF AG, Sewing Machine Factory, KAISERSLAUTERN
>/- •
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Ind ex
Section
Brief Description of the Machine
Varieties of the PFAFF 435
1. Setting Up the Machine
2. Filling In the Oil
3. Testing the Machine
4. Taking Qjt the Bobbin Case Cover ...
5. Winding the Bobbin
6.
Threading the Bobbin Case
7. Threading the Needle
8. Drawing Up the Bobbin Thread
9. Regulating the Thread Tensions .
10. Regulating the Pressure on the Material
11. Choosing the Proper Needle
12. Changing the Needle
13. Regulating the Length of Stitch .
14. The Knee Lifter
15. The Hook
16. The Mechanical Opener
17. Tilting the Head of the Machine . . . .
18. Taking the Hook Apart
19. Service and Maintenance
Instructions for Mechanics
20. The V-Belt Drive
21. Regulating the Automatic Lubrication System
22. Regulating the Lubrication of the Head Parts
23. Regulating the Lubricalion of the Hook . . .
24. Changing the Oil
Page
2
2
2
3
10
11
12
13
14
14
14
15
16
18
20
21
22
23
25
25. Regulating the Throw of the Threcid Check Spring 25
26. Setting the
Needle Bar at Correct Height .
27. Timing the Hook
28. Changing the Hook
29. Timing the Mechanical Opener ....
30. Disassembling the Link Take-up ....
31. Adjusting the Length of Stitch for Forward and Reverse Feeding
32. Removing the Oil Reservoir and Taking the Oil Pump Apart
33. Probable Causes of Sewing Troubles .
27
28
29
29
31
34
35
36
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Instruction Book
PFAFF 436
One Needle Lookstifch Superspeed Sewer
with Automatic Lubrication
This Instruction Book contains useful instructions for
operators and mechanics alike and therefore should be
made available to both rather than put away In your files.
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PFAFI= 436
Brief Descrlpfion of the Machine
The PFAFF436 One Needle Lockstitch Superspeed Sewing Machine, fitted
with link take-up and horizontal rotary hook, in its mechanical set-up may
be regarded as an improved model of the PFAFF 134. The high sewing speed
of this machine, ranging from 4,000 to 5,000 stitches per minute depending
on the grade of material sewn, has mode it mandatory that it be provided
with a forced feed lubrication system.
Since the manipulations required for this machine, such as for threading
the needle, regulating the length of stitch, and tying off seams, have not
been changed, operators need not bs retrained and expenses for such re
training are eliminated.
With its
modern, functional design, sturdy construction, and its sewing
properties of highest perfection, this machine satisfies any demand in all
branches of the sewing industry.
Variefies off the PFAFF 436
The PFAFF 436 is availoble in the following three varieties:
Model
Class of Work
Maximum
Length of Stifch
(Stitches p.
Indit
Maximum
Speed (Stitches
per Minute)
Needle
System
Presser Foot
Clearence
A
Sheer, light
weight fobrics 75,000
133 R
''Ua"
BMedium
weight
fabrics
64,800
134 R
CMedium
heavy
fabrics
5'/,
4,500 134 R"/ic '
The above models of the PFAFF 436 differ in regard to the maximum
length of stitch, the needle bar rise, the presser foot clearance, and the
take-up motion, and thereby are particularly adapted to the class of work
they are intended for.
1. Setting Up the Machine
In most instances the PFAFF 436 is fitted for individual power drive to
be
set up on on individual power table.
The machine is driven by a '/» HP motor, friction clutch type. (Type of
current and tension optional to suit local requirements).
Power is transmitted from the motor to the sewing machine by means
of a V-belt, 2V0.1" wide (DIN 2215).
For 50 cycle current, a motor performing 2,800 R.P.M. should be used,
whereas for 60 cycle current, a motcr performing 3,400 R.P.M. would be
appropriate.
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The motor pulley can easily be exchanged to alter the maximum number
of stitches
per minute of the machine.
The below table should be consulted for all data regarding the maximum
number of stitches obtainable in relation to the various motor pulley diame
ters.
Diameter of
Balar^ce Wheel
50 Cycles 60 Cycles
Diameter of
Motor Pulley
Stitches
per Minute
Diameter of
Motor Pulley
Stitdies
per Minute
(64 mm)
3'Vei" (95 mm)
3'"/ic" (100mm)
4'Vg4" (106mm)
4%2" (112mm)
4 (118 mm)
4,200
4,400
4,600
4,800
5,100
3 (80 mm)
3'Vn2" (85 mm)
3
35/^,," (90 mm)
3^'/c.i" (95 mm)
3";ic" (100 mm)
4,200
4,500
4,800
5,000
5,300
Head and stand are packed separately. The head should be unpacked
very carefully lo avoid damage. After taking off the lid of the box, unscrew
the wood screws holding the cushioned wooden blocks supporting the
machine head inside the box. Take the head out carefully, remove the dust
thoroughly, and set it up on the rubber pads on the table. To facilitate
mounting the rubber V-belt, place the belt on the machine pulley, lift up
the motor somewhat, and than pull the belt on the motor pulley. Setting
the V-belt tension is instructed in Section 20.
The machine Is dispatched without oil filling in the oil reservoirs and must
not be run while in this condition!
2. Filling In ihe Oil
The amount of oil required for the first two fillings comes with the
machine in a can. It is a spindle oil, viscosity 3.2° Engler
at 20° C, which
has proved very satisfactory for the lubrication of the PFAFF 436. To fill
Photo 1
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in the oil, proceed as follows: Remove screw d (Photo 1), fill in about 1pint
(0.5 1) of oil, and wait a few minutes until it has accumulated in the oil
reservoir. Now check at the oil level gauge in the front of the oil reservoir
(Photo 2) if the amount of oil filled in is sufficient. The oil level should be
between the two marks indicating the maximum and minimum levels of 0.6
and 0.3 I respectively with the machine being idle. Under no circumstances
should the top cover be removed and oil be filled in there. Experience fias
shown that it is of advantage to lubricate the hook separately. Oil reservoir
b serving this purpose is on top of the machine arm (Photo 1). To fill up the
hook oil, remove screw c, and fill in approximately 4.5—4.9 cu. in. (75—80
cm^) of oil. ,As long
as the red point of the float .spindle is visible in the
oil level tube while the machine is in operation, there is sufficient oil in the
reservoir. If, however, the red point of .the float spindle is flush with the
top surface of the oil sealer nut, oil should be filled up.
Photo 2
3. Testing the Machine
It Is recommended to test-run the machine with thread and bobbin case
removed. First of all, however, make sure that the line voltage corresponds
with the voltage given on the rating plate of the motor, and that the ma
chine pulley rotates in the proper direction, i. e. toward the operator. Never
must the motor rotate in reverse direction. Therefore, before running the
machine, cut in the
motor, hold the balance wheel with your right hand, tip
on the
treadle, and make sure by the jerk of the balance wheel that it
rotates in the proper direction. If not, simply exchange the two motor ter
minals. Now press down the treadle and, while running the machine, check
ot the oil gauge dome on the top of the machine arm if the pump works
correctly (indicator cap in top position).
For regulating the hook lubrication
system, see Section 23.
Note: Never run the machine unless a piece of fabric is inserted under
the presser foot or the latter is raised.
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4. Taking Ouf fhe Bobbin Case Cover
Raise the thread take-up to its highest position, open the bobbin case
latch with the thumb nail of your left hand, and, by means of this lotch,
pull the
bobbin case cover out as shown in photo 3.
Note: As long as the latch is open, the bobbin cannot fall out of the
bobbin case.
iilTiTIM
SYSTEM ISA-
Photo 3
5. Winding the Bobbin
For this operation the bobbin winder for power drive (Photo 4) is used
which features a number of improvements.
The bobbin winder spindle runs in a sintered steel bushing making lubrica
tion of the winder completely superfluous.
To reduce the high speed somewhat, the diameter of the bobbin winder
pulley has been increased to
The rim of the pulley was given a V-shaped profile so as to make the
concave bottom surface of the V-belt fit on it well. If necessary, even a
round belt can be used.
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hjLv
Photo 4
Fasten the bobbin winder to the table with its driving pulley for enough
from the machine belt so that it will not touch the belt when the winder
is disengaged. Awindshield mounted on the winder base prevents the
thread from being dragged over toward the belt by the suction. An adiust-
oble leather pad mounted on the base serves to stop the winder silently.
Pass the thread from the spool 1through eyelet 2, clockwise around and
between the tension discs 3, to the bobbin. Now pass the end of the thread
inside-out through the slot in the face of the bobbin, place the latter on
the bobbin winder spindle 5, and hold the loose end of thread until the
winder has made a few revolutions. Start the winder by pressing down the
flap of engaging lever 6. When sufficient thread has been wound on the
bobbin, the wincier will stop automatically. The amount of thread to be
wound on the bobbin is regulated by screw 7.
Turning it right—More thread
Turning it left —Less thread
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6. Threading ihe Bobbin Case
Insert the full bobbin into the bobbin case cover so that the thread un
winds clockwise (Photo 5).
Pull the thread into the slot 1, and draw it under the tension spring into
the delivery
eye 2. Place the bobbin case cover with the bobbin on the
center stud in the bobbin case base so that the bobbin case latch points
toward the operator. Press the bobbin case in until it clicks in position
audibly. This is very innportant
as otherwise needle or bobbin case breakage
may result.
Photo 5
7. Threading fhe Needle
Threading the PFAFF 436 presents no difficulty since the thread, as with
PFAFF 133/134 machines, passes in plain view of the operator (Photo 6) so
that every user should be familiar with it. Pass the thread from the thread
unwinder to thread guide pin 1 and, to prevent vibration of the thread at
high speed, through both of its holes. By the same token, pass it through
all three holes in fhe thread retainer 2 as shown in photo 6, and then be
tween tension discs 3, to threod check spring 4, below guide 5, through
guide 6, right-left through the take-up eyelet 7, down to thread guide 8 and
needle bar eyelet 9, and left-right through the needle eye 10.
8. Drawing Up the Bobbin Thread
Hold the end of the needle thread, and turn the balance wheel toward
you until the needle moves down and up again, thus catching the bobbin
thread which comes up through the needle hole in a loop (Photo 7). Place
both threads back under the presser foot.
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Photo 6
Basic Rule: Stop the machine or commence sewing only with the take-up
in its highest position.
This precaution should always be taken to prevent jamming of the thread
in the hook race, or slipping out of the needle eye. In this case it is no't
necessary to hold the needle and bobbin threads when commencing to sew.
9. Regulating the Thread Tensions
To obtain a perfect seam, observe the following points:
The needle and bobbin threads should be locked in fhe center of the
material as shown in Fig. 8.
Turning the tension nut M clockwise makes the needle thread tension
tighter; turning it counter-clockwise will make it looser (Photo 6).
8
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Photo 7
Fig. 8
The bobbin thread tension is regulated by means of the small hook screw
driver. Turning tension screw zclockwise mokes the tension tighter; and
turning it counter-clockwise, looser (Fig. 9).
Fig. 9
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The tensions should be reguloted in accordance with the material used
and so as to obtain tightly set stitches forming a nice and straight seam,
without puckering the material.
For this purpose the grade of thread used plays adecisive role.
Thus, for sheer fabrics a thin and soft thread should be used. Stiff and
resistant thread due to its low elasticity is unfit for practically any fabric.
To properly regulate the thread tensions requires some experience until
one can tell whether the needle thread tension is too tight or the bobbin
thread tension too loose as shown in Fig. 10.
In Fig. 11, the needle thread tension may be too loose or the bobbin
thread tension too tight.
Fig. 10
Fig. 11
The operator will have to decide in any particular case if either the
needle or the bobbin thread tension requires appropriate adjustment, parti
cularly if the thread forms small knots or loops on the upper or underside
of the fabric.
Note: The needle thread tension can only be adjusted with the presser bar
lowered as raising the presser bar automatically releases the tension.
10. Regulating the Pressure on the Material
Smooth and even feeding of the work as well as preventing chafing of
the material by the teeth of the feed dog depend on the setting of the
proper amount of pressure to be exerted on the material by the presser
foot.
Turning presser bar adjusting cap screw V (Photo 20) inwardly will in
crease the pressure for heavier materials; turning it outwardly will ease the
pressure for lightweight materials.
Note: When stitching delicate and flimsy fabrics, it is recommended to feed
apiece of tissue paper underneath the material which will protect
the underside of the moterial, prevent puckering, and can readily be
torn off afterwords.
10
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11. Choosing fhe Proper Needle
Standard round-shank needles with round point and shank diameter
are used with the PFAFF 436. Model A mochines for sheer fabrics require
short needles, System 133 R, whereos Model B and Cmachines use needles,
System 134R, which are longer. The standard shank diameter of
is imprinted on the needle wropper.
The needle is of eminent importance for obtaining a perfect seam and
therefore should be chosen in proper relation to the thread and fabric
weights used.
For lightweight fabrics, a thin needle should be used to prevent ugly
needle marks in the fabric.
When using a thin needle with a thick thread, the thread is likely
to breok, ond, conversely, when using thin thread in a thick needle, skip
ping of stitches may occur as a result.
Select the proper needle from the chart below:
Needle and Thread Chart
Needle
Size
Thread Weight
Needle
Size
Thread Weight
70
75
Cotton 100-80
Silk, short fiber 100/3
Silk, genuine 100/3(0)
100
Cotton 40-30
Silk, short fiber 60/3
Silk, genuine 60/3 (D)
Linen thread 90-80
80
85
Cotton 80-60
Silk, short fiber 80/3
Silk, genuine 80/3
(B)
110
Cotton 30-24
Silk, short fiber 50/3
Silk, genuine 50/3 (E)
Linen thread 80-50
90
Cotton 60-40
Silk, short fiber 70/3
Silk, genuine 70/3 (C)
120
Cotton 30-16
Silk, short fiber 40/3
Silk, genuine 40/3
Linen thread 60-40
Note: We warn you to use needles of unknown origin even if the needle
wrapper should bear the inscription "Needles for Pfaff Sewing
Machines" plus the needle system.
Never use rusty needles!
Only fhe exceptional quality of the finish of the needle ensures trouble-
free sewing and prevents thread breaking. Due to the high speed of the
PFAFF 436, a
needle with a rough surface gets hot quickly and thus burns
the
thread. This is particularly true of Nylon thread which is very sensitive
to heat and melts easily.
11
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If the standard needle shoyld get too hot when stitching in dense mate
rial or running the machine for a longer time, it is recommended to ex
change the ordinary needle for a mirror-finished, chromium-coated high
efficiency needle, Systems 133 or 134, which may be procured from us.
12. Changing'the Needle
1. Raise the needle bar to its highest position.
2. Loosen the needle set screw o (Photo 6) with the small screw driver.
3. Pull out the needle.
•,^i
Photo 12
12
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4. Insert new needle, Systems 133 R or 134 R, with the short groove facing
right
end push it up as far as it will go.
5. Tighten the
needle set screw a firmly.
13. Regulating ihe Lengfh of Stitch
The PFAFF 436 is fitted with the proved spring-activated stitch regulator
which con be set for the length of stitch desired by turning the thumb nut A
(Photo 2). A special device locks the length of stitch set so that it cannot
be changed inadvertently while sewing. The numbers on the scale indicate
the length oF stitch in miLimeters. Through pushing the stitch regulator lever
up
as far as it will go, the machine is set for reverse feeding.
Shifting the machine to
reverse stitching can either be done by hand or
by
foot control. After letting go of the stitch regulator lever, it will automa
tically return to its initial position. The treadle for the stitch reversing device
/
Photo 13
13
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is arranged at the left to relieve the right leg which has to actuate the knee
lifter. Through this device both hands are free to manipulate the work
(Photo 12}.
14. The Knee Lifter
The PFAFF 436 is fitted with a knee lifter device which is harmoniously
connected with the heod of the machine.
The presser foot is either lifted by raising the presssr bar lifter by hand,
or by actuating the knee lifter with the right knee. The knee lifter
pad can
be adjusted horizontally and vertically. For horizontal adjustment, loosen
screw b and adjust at screw a; for vertical adjustment, loosen screw c
(Photo 13). To permit tilting the head back, the knee lifter shaft with the
knee lifter can be pulled off after pulling out piston pin d (Photo 18) which
can
easily be reached through an opening in the dress guard.
15. The Hook
The PFAFF 436 is fitted with the proved hook of Model 134, rotating
twice per cycle. The only difference between previous models and this one
is
that the PFAFF 436 hook is provided with centrifugal lubrication.
The hub of the hook
shaft is provided with an oil retainer ring which,
being properly
balanced, ensures an absolutely vibrationless running of the
hook. The oil emerging from a hole in the hook shaft bushing is atomized
by centrifugal force and then enters the hook race through asecond bore
where it effects adependable and permanent lubrication.
The amount of oil, set for average sewing requirements at the factory,
can be regulated after removing the needle plate as instructed in Section 23.
This job, however, should only be performed by a mechanic.
16. The Mechanical Opener
All varieties of the PFAFF 436 are fitted with positive mechanical opener.
Since the
advantages of this device are not generally known, we should
like to add a few explanations here.
With a lockstitch machine the locking of the needle
and bobbin threads
is done in two different ways, depending on the class of machine. Either,
as with oscillating or vibrating shuttle machines, the threads are locked by
passing the bobbin thread in a shuttle through the needle thread loop which
has been formed while the needle, having passed the lowest point of its
downward stroke, is rising, or by passing the needle thread loop around
the bobbin case with the latter being in a stationary position.
14
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In machines having oscillating loop takers, such as central bobbin ma
chines, the loop forming part, while moving back and forth, passes the
needle thread loop around the
bobbin case with the latter being mounted
in a cenfral or eccentric position.
With the type of loop taker generally used for high speed sawers, the
horizontal hook rototing twice per cycle,
which isalso used in the PFAFF 436,
the needle thread loop is passed around the stationary bobbin case at every
other revolution of the hook.
With rotary hook machines, having no mechanical opener, the needle
thread, after having been passed around the bobbin case, has to turn the
bobbin case slightly making an opening through
which it can pass.
With the increasing sewing speed the friction between the hook race
and the bobbin case increases accordingly and causes the bobbin case stop
to increase its pressure on the bobbin case position finger. As a result, the
needle thread has to overcome astronger resistance when passing between
the stops. This intensified strain, in turn, can only be overcome by easing
the thread tension to prevent thread breaking.
The drawback of this remedy lies in the fact that in most cases the
needle thread tension has to be eased to an extent which makes proper
setting of stitches impossible if the machine is operated at reduced speed.
To eliminate these disadvantages, PFAFF High Speed Sewers are fitted with
omechanical
opener, whereby a small lever mounted on the mechanical
opener shaft assumes the function of moving the bobbin case back sligthly
at the proper moment and contrary to the rotating direction of the hook.
This way the needle thread is permitted to pass freely between the position
finger and the bobbin case stop. The advantages of this device for high
speed sewers are manifold. First the needle thread tension need not be
changed, irregardless of the sewing spead, since the needle thread is not
exposed to additional or evar-changing strain. As a result, also for sheer
fabrics the thread tensions can be set so as to ensure even setting of the
stitches and to prevent puckering of the material at all speeds. Second,
threads of a low tensile strength may be used on this machine even for
high sewing
speeds since the danger of thread breaking has greatly been
eliminated. Third, also while the bearing surfaces of the hook have not
become completely smooth yet, the machins will sew flimsy fabrics at
top speed.
All of the above advantages account for the fact that also the varieties
of the PFAFF 436 intended for heovier materials are fitted with the positive
mechanical opener.
Timing of the mechanical opener should only be performed by a mechanic
as instructed in Section 29.
17. Tilfing fhe Head of the Machine
To facilitate the removal of lint having accumulated between the,feed
dog and the hook, the machine can be tilted back after taking off the
knee lifter.
15
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For this purpose, reach through the hole in the middle of the dress guard
under the table and pull back the piston pin d (Photo 18). Then the knee
lifter with the knee lifter shaft can be pulled out at the front. Having done
this, the head can be tilted back and rested on the wooden machine rest
or on the sew light bracket after the latter has been swung off.
18. Taking the Hook Apart
Skilled operators who make it a routine to start or finish a seam only
with the take-up in its highest position, or to place the threads back under
the presser foot when commencing to sew,
will hardly ever encounter thread
jamming in the hook race.
Should thread jamming occur, however, first try to get a hold of the
loose end and to
pu-l it out while jerking the balance wheel back and forth.
If this attempt fails, take the hook apart, proceeding as follows:
Photo 14
16
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1. Tilt the head back as instructed in Section 17.
2. Raise the needle bar and the take-up, provided the balance wheel can
still be turned. If not, remove the bobbin case position finger bracket a
(Photo 14) first.
3. Loosen set screw c and pull off the mechanical opener lever b. When
reassembling the parts, the proper position of the mechanical opener
on the shaft can easily be reestablished since the shaft is marked by a
groove.
4. Pull out the bobbin cose cover with the bobbin, seizing it by the latch
with thumb and forefinger.
5. Raise the head of the machine and remove needle plate and feed dog.
6. Loosen screws, e„ e®, and O;) (Photo 15) and take off the hook gib d
which, however, should not be confused with the hook body guard f.
Photo 15
7. Turn the balance wheel until the first screw f, in the hook body guard f
is opposite notch I in the bobbin case (Photo 16). When in this position,
the bobbin case base can be taken out of the hook. Photo 17 shows the
hook components in the some position whereby it should be noted that
point 1 of the bobbin case base should be between point g of the hook
and point f of the body guard.
17
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8. Seize the bobbin cose base with thumb and forefinger, pull it to the
left and down, and take it out.
9. Clean the hook and the bobbin case base thoroughly, and remove fluff
with o pointed wooden instrument, never with a screw driver.
10. Before replacing the bobbin case base, it is recommended to screw on
the bobbin case position finger bracket a. Then insert the bobbin case
base but make sure that the finger h engages in notch i in the bobbin
case base and that aclearance about .019" wide is preserved between
the tip of the finger h and the bottom of the notch I.
n. Replace hook g'b d and tighten screws Oj, e^, and e;,.
12. Push the mechanical opener lever on its shaft whereby screw c should
engage in the lengthwise groove in the shaft and the lever should cover
obout '/a of the projection on the rim of the bobbin case base. Then
tighten screw csecurely (Photo 14).
!r
Photo 16
19. Service and Mainfenance
Due to the PFAFF 436 being provided with automatic lubrication, there
ishardly any maintenance required while the machine is in operation. Merely
the automatic
lubrication system should be checked, oil filled up, and the
machine cleaned regularly.
When the machine is in constant use, it is urgently recommended to moke
it a daily routine to remove with abrush the lint and fluff that have accu-
18
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