Pfaff 438 Service Manual

®

438

Service

PFAFF

INDUSTRIEMASCHINEN

Manual

GMBH

KAISERSLAUTERN

Instructions

and

Illustrated

The

machine

which

has

been

I

Note:

Never

mightbedamaged

for

Adjusting

Guide

for

Tape-Recorded

we

had

In mind in drawing up

repaired,

but

useaneedle

by

still

needs

rise

the

C-clampofthe

the

Pfaff 438

Instructions

the

adjusting.

gauge

on

gauge.

following

the

Pfaff

instructions

438

because

is a

machine

its

needle

bar

Tools,

the

1

2

1

Gauges

Pfaff

438

setofscrewdrivers

setofwrenches

setofalien

cylindrical

feed

dog

gauge,

hook

bearing

wrapper

stripsofwhite

reelofadhesive

sewing

with

thread

and

from

screw

wrenches

pin, 32 mm

Order

bracket

System

paper

tape

Accessories

with

blades

7—14

mm

long,

No.

gauge,

438

needles,

Required

from

2-10

in

sizes

from

6 mm

dia.

91-129 995-05

Order

No. 91-129 996-05

No. 80

for

mm

wide

2—6

mm

No. 13-030 341-05

Adjusting

1.

Preparations

for

Adjusting

1.1 Determining the Different Needle Positions (Fig. 1)

1.1.1

The

bearing

plateatthe

needle

bar

endofthe

machine

conjunction with a 5-mm pin, determine the different needle positions.

1.1.2 Hole 1 =

1.1.3

Hole

1.1.4 Hole 3 = 0,25 mm (abt. .01")

1.1.5

Hole

Needle

bar

2 =

Topofneedle

4 = 1 mm (.04")

rise

stroke

position 2 mm (abt. Vsi")

bar

stroke

past

the

highest

past

the

highest

pointofthe

above

pointofthe

needle

has

four

the

bottomofthe

needle

bar

holes,

bar

stroke

which, in

needle

stroke

5

Fig. 1

1.2

Removing

1.2.1

Turn

out

remove

1.2.2

Takeupthe

moveitwithavacuum

the

screws

cover.

Cast-iron

Softhe

oil in

the

Cover

cast

needle

pump.

(Fig.

2)

iron

vibrating

cover

on

the

eccentric

backofthe

housing

machine

with a

sponge

arm

and

or

re

Fig.

2

1.3

Removing

1.3.1

Turn out screw 6 of the presser foot and remove the presser foot.

Various

Parts before

Adjusting

the Needle Bar

(Fig.

3)

1.3.2 Turn out screw 7 of the thread guide, too, and remove the thread guide.

1.3.3

Loosen

from

1.3.4

Turn

arm

1.3.5 Insert a new System 438 needle and push it up as far as It

and

the

out

screw

presser

the

remove

8 of

three

bar

the

bushing

alien

cover.

slack

screws

thread

control

by pulling It

9 of

the

and

remove

downwards.

coveronthe

the

thread

slack

undersideofthe

will

go.

control

machine

Fig.

3

2.

Centering

the

NeedleInthe

Needle

Hole in

Sewing

Direction (Fig. 4)

2.1 Bring

2.2

Loosen

2.3

Loosen

2.4

Turn

is

centered

2.5

In

this

the

needle

jam

alien

eccentric

position

nut

in

screw

stud

the

bar

10.

12 on

needle

tighten

to its

11atthe

the

holeinsewing

alien

lowest

position.

bottom

right-hand

screw11as

of

the

sideofthe

direction.

wellasjam

needle

bar

frame.

machine

nut

arm

until

10 firmly.

the

needle

Fig.

4

3.

Setting

3.1

Remove

3.2

Raise the needle

3.3

Block

of

3.4

Loosen clamp screw 15 at the bottom end of the stabilizing rod.

3.5

Loosen screw 18 (accessible from the back of the machine arm)

clamp

3.6

Then

Turn eccentric stud 17 to

3.7

the

Stabilizing

the

face

the

machineInthis position by inserting the

the

bearing

crank

loosen

plate.

19 in

jam

Rod

Paraiiel

cover.

bar

to Its highest point.

the

machine

nut

16.

set

stabilizing rod 13 parallel to the needle bar.

arm.

to the

Needle

Bar

(Fig.

5)

5-mm

cylindrical pinInhole 2

Be careful that you don't turn the eccentric stud by 180 degrees.

3.8

Hold

eccentric stud 17 in this position and tighten jam nut 16 securely.

3.9

Push up stabilizing rod 13 as far as It

will

go, making sure that the eccentric

stud enters the recess at its top end (see arrow in Fig. 5) and tighten clamp screw

15 on

clamp

crank19securely.

3.10

Remove the cylindrical pin from the bearing plate.

3.11

Bring the needle bar to its lowest point and tighten screw 18 on the back of the

machine

firmly.

which

secures

Fig. 5

4. Adjusting

4.1 Zeroing

4.1.1 Flick

4.1.2 Loosen straight-stitch regulating

maximum

the

Stitch Width Control

the

Needle for

needle

position lever 20 to its central position.

Straight

Stitching (Fig. 6)

screw23and

stitch

width.

stop

screw

24 for limiting

the

4.1.3 Loosen clamp screw 26 of locking lever 22 and let lever 22 swing back until its

springiscompletely

4.1.4 In this position, tighten

4.1.5

Move

stitch

width

4.1.6

towards

Turnonthe

lever

21 to

"0".

the

4.1.7 In this position,

will go

4.2

Adjusting

4.2.1

Move

4.2.2

Loosen

4.2.3 Adjust

flangeofthe

4.2.4 In

this

and

the

stitch

both

the

position,

tighten

width

scale

master

left until

push

Stitch

screws

stitch

tighten

relaxed.

clamp

screw26again.

lever

21

counter-clockwise

switch

and

let

the

needle

straight-stitch regulating

it.

Width

Scale

(Fig. 6)

lever21to

25ofthe

until

width

the

lever.

both

the

rightasfarasit will

stitch

zero

mark on

screws

the

bar

width

25 of

as

machine

stops

swinging

screw

scale.

the

scaleisopposite

the

scale

far

as

it will

run slowly.

sideways.

23 to

go.

securely.

go,

that

Move

stitch

the

rightasfarasit

the

mark on

means

width

the

Fig. 6

4.3 Limiting the

4.3.1

Move

mark

4.3.2 Move it will go

li for

whose hole is smoller thon the widest needle throw, limit the

ol the needle hole rother than the groduotion mark on the stitch width scale.

4.4

Adjusting

4.4.1 Loosen Make

4.4.2 Pull

locking

Maximum

stitch

\wjdth

lever 21 to the left until the mark on its flange is opposite the

indicating

stop

cerfoin

clamp

sure

the

screw/ 24 which limits

and

tighten

sewing

operations your

the

Locking Lever (Fig. 7}

screw

the

pressure

lever22forward

Stitch Width (Fig. 7)

maximum

it.

26 of locking lever 22.

stitch

the

machine

springinthe

until it

w/idthonthe

maximum

locking lever

contacts

should

stitch

hove

stitch

scale.

widthtothe

been

equipped

stitch

does

width

with

width according to the width

not fail out.

lever

21.

4.4.3 In this position, turn hinge stud 27 in or out until locking lever 22

right

amount

of play.

Then

tighten

clamp

screw26securely.

leftasfar

a needle piole

has

just the

as

Fig.

7

5. Adjusting

5.1

Make

sure

width

leveristurned

5.2

Bring

the

5.3

Loosen

5.4

Now

turn

ways.

5.5

Retain

the

that

needle

jam

nut

eccentric

Needleinthe

the

stitch

to

"0".

bar

to its

10 of

eccentric

stud28until

stud

28 in

width

lowest

this

Needle

lever

stud

the

position

Hole

is stiil In its

position.

28 on

needle

and

Sideways

the

undersideofthe

is

centered

tighten

(Fig. 8)

central

jam

position

in

the

nut

and

machine

needle

10 firmly.

the

hole

stitch

arm.

side

Fig.

8

6.

Adjusting the Needle Throw (Fig. 9)

6.1

Loosen

both

screws

29 of the

needle

vibrating

eccentric

mit the eccentric to be turned on its shaft against strong resistance.

6.2

Bring the needle bar to its highest point. Insert the

bearing

tion.

6.3

Move

Vii")

6.4

Turn the eccentric on its shaft

stitch

6.5

Pull the cylindrical pin out of the bearing plate.

Do not tighten screws 29 of the needle vibrating eccentric yet.

6.6

2®(i((0

plate,

thus

blocking

the

the eccentric on its shaft

between

width

its

right-hand

leverismovedtoand

side and the

machine

until

with

the needle bar in its highest posi

there is a clearance of about 5.0

wall

of the casting.

the needle bar ceases

fro.

just

sufficiently

5-mm

pin in hole 2 of the

vibrating

to per

mm

while

(or

the

Fig. 9

7.

Adjusting the Needle Throw in Relation to the Central Needle Puncture

7.1

Move the needle position lever to its central position and the stitch width lever

to

"0".

7.2

Place a piece of white paper under the needle. Turn the balance wheel in sewing

direction until the needle

a

little.

7.3

7.4

7.5

7.6

7.7

7.8

Hold the

mum

Rotate

stitched

Remove the

rection Place

the

Turn

paper

Since

the

paper

stitch

the

into

one

the

paper

first

hole.

the

stitch

again. the

eccentric

width.

balance

the

paper

complete

two

punctures must be moved in

rotate

the

eccentric

7.9

After you

(see

arrow

have

in Fig. 10) up

in its original position and turn the stitch width lever to the maxi

paper

under

width

screws

slightly on its

completed

has

wheelinits

again.

pierced the

normal

paper

slightly and then raise the needle

directionofrotation

until

from under the needle, turn the balance wheel in sewing di

turn

and

flick

the

needle

levertothe

29 of

shaftinthe

while

moving it

the

against

stitch width lever

again

and

position it so

widest

stitch

and

the

needle

vibrating

eccentric

direction in which

order

to obtain a symmetrical stitch pattern. (Don't

endwise

adjustment,

the

eccentric.

on its

tighten

screws29and

let

the

shaft.)

back that

needle

are

the

to "0".

the

still

two

the

needle

stitch

push

needle

loose,

outer

the

(Fig.

enters

into

needle

circlip

10)

has

ttxe

move

1 <

) Fig. 10

10