Pfaff 238 User manual

PFAFF
238
238-0
I
R 9030
Instruction Book
and
Service Manual
From the library of: Superior Sewing Machine & Supply LLC

/hphee ^ 238
( PFAFF) 238-0
High-Speed Zigzag Sewing Machine
Organized with iink take-up
and transverse rotary hook
instruction Book
and
Service Manuai
G-MPFAFFAG-KAISERSLAUTERN BRANCH
From the library of: Superior Sewing Machine & Supply LLC

Foreword
This Instruction book contains much vaiuable Information about Pfaff 238 and 238-0
high-speed zigzag sewing machines. Though not intended as a full-scale textbook capable
of answering all questions related to sewing exhaustively, it offers sufficient information
on the construction, function and operation of the various mechanisms to enable every
interested operator to get to know her machine and attain maximum efficiency as quickly
as possible.
The instructions for mechanics contained in the second part of this book will no doubt
be much appreciated by all maintenance men servicing our sewing machines since even
the best sewing machine will work satisfactorily only if it is employed properly and
serviced by an expert. We have made every effort to render the presentation of these
instructions as simple as possiblle and have included numerous illustrations in order
to afford a better understanding. We welcome any suggestions and recommendations
which you may wish to make.
G. M. PFAFF AG
From the library of: Superior Sewing Machine & Supply LLC

From the library of: Superior Sewing Machine & Supply LLC

Instructions for Operators
1. Brief Description of the Pfaff 238
The Pfaff 238 high-speed zigzag sewing machine Is an Improved version of the Pfaff 138
which has been redesigned to match our modern high-speed straight stitchers In out
ward appearance and sewing performance.
Like the Pfaff 138, It Is organized with link take-up and transverse rotary sewing hook
which features aspecial balancing collar In order to
ensure vibratlonless running.
The Pfaff 238 Is supplied in Models A and B for a maximum stitch length of down to 7
stitches per Inch.
The permissible top speed of the machine depends on the model and the stitch width.
Model B machines are normally fitted for a stitch width of 11/64", or 4.5 mm, and a top
speed of 3,500 s.p.m.
If desired, Model B machines can be fitted with a special parts set for a stitch width of
about 'A", or 6.0 mm, and maximum speed of 3,200 s.p.m.
As a special variety, the Pfaff 238 can be supplied In Model A for a maximum stitch
width of 5/32" and a sustained speed of 3,800 s.p.m.
2. Setting Up the Machine
In most Instanoes, the Pfaff 238 Is supplied for Individual power drive. Sewing head and
power table are packed separately.
The machine Is driven by a Va-HP clutch motor. (Type of current and voltage optional to
suit local requirements.)
Power Is transmitted from the motor to the sewing machine by means of a V-belt 25/64",
or 10 mm, wide and conforming to German DIN 2215 standards.
When connected to a 50-cycle power supply, the motor runs at a speed of 2,800 r.p.m.,
and when connected to a 60-cycle power supply, at 3,400 r.p.m.
The motor pulley can be easily exchanged In order to vary the maximum sewing speed,
as may be required.
The relationship between pulley diameter and maximum sewing speed Is Indicated In the
table below:
From the library of: Superior Sewing Machine & Supply LLC

Balance
Whppj nip.
Motor Speed 2,800
r.p.m.
Motor Speed 3,400 r.p.m.
dm
mm
D
mm
dm
mm
Motor
D
mm
Pulley Dia.
Order
No.
Stitches
per
Minute
dm
mm
Motor Pulley Dia.
D Order
mm No.
Stitdies
per
Minute
71 76 63 68
16-437 010-55 2,500 ---
71 76 67 72 16-437 020-55 2,600 - - - -
71 76 71 76 16-437 030-55 2,800 -- -
-•
71 76 75 80 16-437 040-55 3,000 63
68 16-437 010-55
3,000
71 76
80 85 16-437 050-55 3,200
67 72 16-437 020-55 3,200
71
76 85 90 16-437 060-55 3,400
71
76
16-437 030-55
3,400
71 76
90 95 16-437 070-55 3,600 75 80
16-437 040-55
3.600
71 76 95
100
16-437 080-55
3,800
80 85 16-437 050-55 3,800
dfn ~ effective diameter 0 = outside diameter
63 mm
= 2.48", 72 mm = 2.83", 85 mm = 3,35",
67 mm = 2.64",
75 mm = 2.95", 90 mm = 3.54",
68 mm = 2.67",
76 mm = 3.00",
95 mm = 3.74",
71 mm = 2.79",
80 mm = 3.15", 100 mm = 3.94".
dm
- 0 Fig. 2
Unpack the sewing head cautiously to avoid damage to the machine. After removing the
lid from the box, unscrew the wood screws which hold the cushioned wooden blocks
that support the machine in the box. Cautiously lift the machine out of the box, wipe off
the dust and mount the machine on the table so that it rests on the rubber pads.
To facilitate the mounting of the V-belt, slip it on the machine pulley first. Then slightly
lift the motor and pull the belt onto the motor pulley.
For adjusting the V-belt tension, please refer to the instructions which are furnished with
the motor.
The machine is dispatched without oil in the reservoir and must not be run while in
this condition.
From the library of: Superior Sewing Machine & Supply LLC

3. The Lubrication System
An oil reservoir has been Incorporated in the top cover of the machine (Figs. 4 &5)
which holds enough oil to ensure adequate lubrication of the arm shaft parts.
After pulling out plug C
(Fig. 3), fill about 4 Vs fl. oz. of ordinary sewing machine oil
(Order No. 280-1-120122) or a technical white oil having a viscosity of 150 R/68°F or
175 S/es'F Into the reservoir.
The oil in the reservoir will last for a longer time, depending on how long the ma<^ine is
in operation each day. Oil should be replenished when the red tip of the oil level gauge
which can be seen through the oil sight glass emerges from the surface of the oil.
Fig. 4 shows the
open oil reservoir with oil wick, Fig. 5 the bottom of the reservoir with
the lower end of oil wick D which protrudes into hole A and supplies oil to the arm
shaft center bearing.
The oil seeps through a vent hole into the hollow arm shaft and is distributed inside the arm
shaft by a packing. Emerging from additional vent holes, oil is supplied to the various
arm shaft bearings and the feed eccentric. Dripping oil is collected by a large oil drip
pan and
accumulates in a detachable plastic oil bottle. (Fig. 6)
R 7715
Fig. 3
From the library of: Superior Sewing Machine & Supply LLC

From the library of: Superior Sewing Machine & Supply LLC

From the library of: Superior Sewing Machine & Supply LLC

The oil which has accumulated in this bottle may be returned to the oil reservoir without
prior cleaning. After the oil has circulated in the machine several times, it Is advisable
to filter it through a piece of linen before it is returned to the reservoir. This will not
Impair its lubricity in the least. Used oil, naturally, may be employed for other lubrication
purposes as well.
All other oiling points which are marked by arrows in Figs. 3, 4, 5, 7 and 8 have to be
oiled by hand.
Special care should be taken in applying oil to the large oiling felt which supplies oil
to the needle vibrating eccentric and can be reached through aperture F(Fig. 5). This
pad should be soaked with oil regularly.
Put one drop of oil into the hook raceway each day the machine is in operation. Fre
quently take off the needle plate and remove the lint which has accumulated on its
underside and on the feed dog. This is very Important because the lint contains small
particles of dressing which have an abrasive effect on the sewing hook and, in time,
will cause excessive wear.
R 7722
Fig. 8
10
From the library of: Superior Sewing Machine & Supply LLC