Bernina 900 User manual

* - A
a
Al I
S* S
A
II
S

Contents
General
information
2
Initial adjustment
operations
4
The needle .. . . .. . . . 5
Needle spacing in the stitch hole
. .. 6
Adjusting the
scanner .
.. 7
Scanner lift
.a... . . .. . 8
Adjusting
the stitch position
L- C-
R
9
Centering the
zig-zag link on the
link spindle 10
Neutral
position
of the needle
12
Lateral needle movement
13
Zig-zag stitch position
.
14
Lateral motion of needle
during zig-zag
and
plain stitch sewing .1.. .
15
Adjustment of the zig-zag width
4,5 mm. . 16
Adjusting the zero
position of the stitch
length crank
16
Adjusting buttonhole
without thread. . 18
Adjusting the
forward and reverse beads 19
Adjusting
the CB shuttle . . . . ....
20
Adjusting the return motion
. ... . . 21
Loop lift
22
Needle height
.,.. .. 23
Lateral
shuttle adjustment
24
Thread guide plate - .
24
Material
feed
25
Feed
dog height . . . . . . . ...
25
Feed dog movement
(Vertical) 26
Presser foot bar - --
27
Upper
thread tension - .
29
Lower thread
tension-
31
Adjusting
the thread regulator spring
32
Foot pressure
33
Winder
34
Retightening the drive belt .
35
Electrical
section - .
36
Adjusting Motor speed .-.. . . .
36
1

Type 9 Z Zig-zag and plain stitch sewing machine
electronic with 6 built-in cams and automatic button-
holer with 5 built-in cams.
Valid for model 900 electronic
trom machine no. 19 200 551
_n _
314 178 Fig. 1
Max. zig-zag width 45 mm
Stitch distribution: Left-Center-Right
Max. forward stitch length 4 mm
Max. reverse stitch lengeh: 2 mm
Presser toot lift: 6.5 mm
Passage space: 105 x 200 mm
Base plate dimensions: 374 x 178 mm
Shuttle system: Jam-free central bobbin shuttle
Bobbin capacity: 75 m cotton yarn
Needle system: 705 B
Needle movement, Swinging needle bar
Thread teed: Hinged take-up lever
Thread tension: Upper thread tensioner in frame
Built-in
Winder: Built-in
Motor Power. 90W
Sewing lamp (built-in) Power- 15W
Number of stitches: Approx 1100 stitches min
Weight (complete) 10i5 kg
2

Setting
needle:
=
705 B-80
Needle deflection:
With
lifting bar
suspension:
2
Needle
plate upper edge:
4.5
At
shuttle
tip: 463
Needle
bar
stroke:
V
33 73
Loop
stroke:
left
1 8
Shuttle
travel:
220
18' 30
Rack
travel:
34.6
Lift
crank
radius
17 3
Take-up
lever travel:
= 61
Presser
foot
lift:
= 6.5
Darner
stroke:
2,92
Speed:
Motor:
7400
rpm
Cone
pulley:
= 2372
rpm
Frame
shaft:
= 1120
rpm
Gear
ratio:
Overall:
6.6
1
Motor:
Cone
pulley
312
1
Cone
pulley: spindle
2,12
1
Base circumference:
245
mm
Machine
dimensions:
Overall
length:
= 399 mm
Overall
width:
178
mm
Overall
height:
350.5
mm
8
12
13
14
16
; 4
22
21
20
Fig
2
3

Initial adjustment operations
Rotate zig-zag knob (13) to postion (0)
Unscrew mounting screw knob (13) and
rF_ emove knob, Set slihch selection knob
(14)
to position (A) -------
Unscrew the
assoc ated
mounting screw
and remove
t * _ 14 _
Knob and scale
together with wheel,
13 i #^i _ gUnscrew both Phiillips screws (130) and
-lr
\ renmove cover
plate (129),
The screws are
riot visible
until knobs (1:.) and (14) hav
been removed Remove frame cover (128)
and end cover
(5) (Light switch
has been
switched ,on>.n
U Temporariy
reinsert zig-zag
krob (13) and
stitch selection knob (14) together with
scale,
r g, 3
Adjustments
can
now be carried
out
After adjustments have been made rein-
sert parts in reverse order.
IMPORTANT: The sewing machine can be
completely adjusted
and sewn oft prior
to mounting covers
14
128 14 Adjustment of the type 900 sewing
5
,
machine
: |
m <:: land other
rnodels)
13 .hese
adjustmen
instructions
are des:g-
Li
ned to assist
mo minor
repairs or
adjust-
130
-
ments of the
BERNINA sewing
machine
~~ 129 f Ol o f ~~tPe 900.
129
tMPORTANT:
The
sewing
mach
ne
must
be in perfect
mechanical
condition
(run-
{ning smoothly.
properly
oiled
etc.) so
tha!
idividual adjustments
can be
carried
out correctly,
-__________________ - If the sequence of adjustments is obser-
ved r peccable
speration
ot the machine
he
onsured

The needle
The needle is one of the most important BERNINA uses the "705 B,, needle system
elements of the
sewing rnachine.
It pier- without fluting
(Singer designation:
15 xl1
ces the fabric
and forms
a loop which
is on
all domestic
sewing machines
with
caught
by the
shuttle and is
joined with
CB-shuttle
hook.
the lower
thread
The loop is
formed after
The metric
system
has been
in unse since
the needle has
pierced the
fabric and has
1947 for needle
thickness designation.
A
reached its
lowest point.
The needle lifts
needle thickness
of 100 means
that the
slightly during the so-called
loop ift needle stem
is 1 mm thick.
The
tightly drawn
thread
which lies
in the (A
No.80 needle
- 0,8 mm:)
long and short grooves
on the front and
The needle must be
firmly secured by the
rear side
of the
needle, respectively,
is knurled
screw
on the needle holder.
caught above the short groove between
the needle
stem and the material, When IMPORTANT:
Always use a No 80 needle
the needle moves upward,
the thread feed for all adjustrnents unless otherwise sta-
is retarded
due to the
friction of
the ted,
Check the
needle prior
to every
ad-
fabric and thereby
a loop. comming from justment of the sewing machine. It must
the
needle eye, is formed on the rear side
always be straight.
of the needle This loop is caught by the
shuttle
tip, widened, and is guided
around
the lower thread supply. The important
features
of the sewing
needle are:
a) shank
for securing
the needle
in the
needle bar
b) stem with
a short and long groove
c) needle eye
d) needle point
e) needle
length
b
d Fig 5

Needle spacing
in
the stitch hole
The rieedle
must penetrate the
center of
the stitch
hole (as viewed
from the direc-
tion of fabric
feed) (needle thickness:
Fig 7
0~~~~
*1
I
most be removed.
Then, loosen
two
of the,
I
three
frame mounting
screws
(Allen
fl51
screws
with an interior
hexagon
width ot
vmm)
an.d move
the machirie
frame urnt
f
the needle
penetrates
the center ot
the
ASt ch
hole. Rotghilen
A: le
r, w Gi
i Fig.
S
6

Adjusting
the
scanner
to
the
center Rotate
handwheel
until
scanner
(119)
isat
of
cam
S
(Running
stitch)
by dis-
the
highest point
of
cam
(120).
Loosen
placing
the
adjusting
drum
mounting
screws
(121)
of
the
adjusting
drum,
Position
the scanner
precisely
in
Set
zig-zag
knob
(13)
to
position
"4-
and
the
center
of
cam
(5)
by
axially
moving
stitch
selection
knob
(14)
to
cam
adjusting
drum
(122)
and retighten
mount-
(D)
ing
screw
(121).
Check
also
the
front
and
rearmost
cam,
:, .
<:D tR l~~~~~~22
4
*__9 12l0
W
129 r
0
138
137
139
Fig 9
::___
127
124
123
~~U ¼
fI |
Fig.
10
7

Raising the
scanner Position
of
lifting
cam
The
scanner
i 19)
is raiset
sjn
the
if
When
the
scanner
(tl9i
is
at
the
inwest
camri
l123K
which
is fitted
c)'
he
.pinidle
poirt
of
the
zigzaq
eanm
there
mus
the
a
below
the
arLjusting
drunm
in f
Ii" gng
illi
little
play between
lifting
arm
124I
and
lt.
i124)
which
is
ad)iustabIe
an
nconnecter
ting
carn 1123)
to the cam
control lever the
play can
he observed by
Lrriiq the
The
lting
arm
124i
is Idlius't
f - as
toilows
stitch
selector
knob
tl4i
gently
iL-and
-ro
Set
z gzag
arijusting knob
( .;
to posit
on
bur;ng
this checs.k
it is
convenient
to
press
.4
and
scanner
to
highest
point
of
zigzag
the
cam
control
leve,
1125)
against the
ziy-
cam.
Place
a 01
15
mm
space,
'12b
be'-
zag
camn
If
no
play
s
apparent
at the
ween
Scanner
and cam
Sel
stit-
h'selector
stitch
selector
knob
(14), correction
shoulcd
knob
(14)
between
zigzag
and biindstitch
be made
as
follows
t oosen
fixing
screw
1127)
or
lifting
arm
loosen
screw
1162i
The
control
sponrig
124)
Fhis
is
drawn
to
the iilting
cam
(123t
it61i
(see
Fig
ila)
can
then
be displaced
by
Ihe
liftinq
arm
tension
Tsprn
'200,
lhe
sideways
until play
can
he observed
at
the
fixing
screw
i127)
is
then retigetened
stitch
selector
knob
14.
Re-tighten
screw
1162)
I
ig
tig.
K
_a;i _ i f U

Setting
the
needle
position selector
L-C-R
(Left-Centre-Right)
Centre
LCR-adjusting
disc with
adjusting
so that the pin
(202} of the LCR
locking le-
tool
no. 39805803
in centre C-position
ver (203) engages
in the centre
notch of
through the hole
in the adjusting
disc and
the LCR adjusting
disc (204)
Re-tighten
frame
(Fig. 13). Loosen
slightly the
two both
fixing screws
(205).
fixing
screws
(205)
of
the
LCR
locking
support
plate
(201). Move
the
support
plate
2Olj ~ ~ 20
Fig. 12
202
204
201
205
9

101
Fig,
14
Centering
the
zigzag
connecting
link
on
oscillating
lever
spindle
Move
control
bar
(101)
of
swivel
support
_-
(115)
to
the highest
posilon
ol
the
zigzag
connecting
link
Loosen
setscrew
(206)
of connecting
sirap
116
W
(207P i
g)gI
Insert
special
tool
no
398
001,04
in
the
v
hollow
oscillat
ng lever
spindle
(116)
and
move
the
connecting
link
gernty
to-and-fro
until
the
conical
tip of
the
tool
enters the
hole
in the
link,
The
link
then
swings
in its
normal
position
about
the
centre
of the
oscillaing
lever
spindle.
In
this position
the
scanning
head
(96)
ot
the
LCR
adjustng
ever (209)
should
lie on
the
cam of
the
LCR
adjusting
screw
under
the action
of the
adjustng
lever
tensioning
_
soring
I213i
Re-tighten
setscrew
i206i
13

Fig, 15
Remove
the
two adjusting
tool
nos.
398
05803
and 398
001
04.
398
058
03
102
96
210
Fig, 16
11

Rest position of needle
It this is nol the case, correction
is mnade
Set stitch selector knob (14M to zigzag as follows.
Move
control bar of swivel support to the
the rest position of the needle
can be set
lowest position 'zero
position! of zigzag by moving
the stop screw (212) SW 5.5 up
connecting link.
or down on the zigzag adjusting
lever (211).
Star
the machine The needle swivel sUp- which
is controlled by a pressure
spring
port must not make any laterai movement,
It must remain stationary Lateral needle movement, transverse
to direction of material.
Set zigzag adjusting knob (13) to "0w
The needle must pierce through the centre
of the stitch hole when the
LCR adjusting
disc
is centered in the C-notch
213 211
212
Fig 17
213
Fig. 18
12

Correct distribution of stitches can
easily head (104) of the adjusting
eccentric. By
be found
by observing the lateral needle
turning slightly to left or right
the lateral
position when the
adjusting screw is tur- needle position
can be set correctly. Re-
ned. In both
side positions the distance
of
tighten screw (103)
after correcting.
the needle
from the edge
of the
The
notch on the
knurled head
(104)
stitch
hole must
be the same.
should be
at the top
Correction
is made
as follows:
IMPORTANT:
Ensure
that there is no
play
Loosen screw (103) slightly. Place
special between swivel support (115) and control
fork wrench
no 39806303 on the knurled
bar (101) when turning the
eccentric.
i _ ~~~lt 95
103 ~~~~~~~104
K -
~~~~Fig.19
7~~~~~~~~~~~~~~~~ -7
-----
L M R
Fig. 19a
115
Fig. 20
13

Stitch
position on zigzag.
It this is not the case loosen setscrew
f17)
In order to set the zigzag sttch position
it of the oscillating lever (18) to which the
is necessary for the sideways motion of zigzag link is attached
and move the need-
the needle to be provisionally set
le to the correct position Re-tighten screw
(1-/L
If the zigzag
adjusting knob
l3)1 s sel
to IMPORTANT:
Ensure that
there is no
play
position .4. and the stitch
selector knob between bearing
and oscillating lever when
(14)
is at <
vXa.
(B),
it can
be determined
moving
the oscillating
lever
(18)e
by turning the handwheel whether the left
and right penetration
of the needle are
equidistant from the edge
oM the stitch
hole
Fig 21
17
Fig 22
14

Lateral
motion
of needle
during
zig-
If
the
zigzag
knob
(13)
is
then turned back-
zag
and
plain
stitch
sewing
wards
and
forwards
between
"0"
and
Ar 4
g ~~~~~~~~~~the
needle
must
remain
stationary!
The
lateral
motion
of
the needle
(parabola)
Correction
is
made
as follows:
must
be
exactly
matched
to the
up and
Loosen
the
two fixing
screws
(105)
of worm
down
motion.
It must
only
begin when
the
(106).
Hold the
worm,
which
is now
loose
needle
has
left
the work
and
must cease
on
the frame
shaft,
with
the aid
of a
screw-
before
the needle
penetrates
the
work
driver
and while
pressing
the
worm
against
again.
The zigzag
motion
is derived
from
a
the setting
ring (107)
turn
the
handwheel
cam.
until
the correct setting
is
found.
Check:
Set LCR
adjusting
disc to
centre position.
Move stitch
selector
knob (14) to
cam B
(zigzag). Set
needle to
uppermost
position
by turning
handwheel.
,,*0 00/S
/
107
105 106
Fig.
23
15

Scanner
support during
backstitch
Check:
If
now
the
zig-zag
adjusting
knob
sewing
(13)
is
turned
from
"0-4<..
the
needle
must
Set
stitch
selector
knob
(141
to
"back-
remain
stationary,
If
this
is
not
the
case,
correction
is
mhade
stitch,
POsition. Turn
LCR-adiusting
disk
as
follows:
(12)
to
<Center"
position
as
follows
loosen
the two
fixing
screws
(214)
on
scanner
piece
(215)
slightly
and
move
the
scanner
support
to
the correct position
with
tool
398
091
03.
Re-tighten
screws
(214),
If
the
needle
moves
to
the
left
when
the
zig-zag
adjusting
knob
is
turned
from
'0-4'<
the
scanner
support
(215)
should
be
mo-
ved
to
the
left,
if
the
needle
movement
is
to
the
right
the
scanner support
must
be
moved to
the
right.
214
214
215
Fig
26
Adjusting
the
zero
position
of
the
stitch
length
crank
Rotate
stitch
length
knob
(22)
to the
0
position
It
is
properly
set
when the imit
stop
can
be
determined
in
the
0
Pos
tion
Use
raw.
2-ply
cotton-oretonne
fro
sewing
material,
place
it
under the
presser
foot
and start machine
16

At
full
machine
speed,
the
material
must
not
move.
If it
does,
correct
as
follows:
l
-
Loosen
setting
ring
(133)
(2
screws)
which
is
mounted
on
adjusting
shaft
(131)
and
rests
against
the
ebackward"
stitch
setting
cam
(132)
and
also
loosen
the
.backward,
stitch setting
cam
(132)
with
the aid
of
Allen
wrench
(134).
Then,
loo-
sen
the
forward"
stitch
setting
cam
(135)
which
is
also
mounted
on
adjusting
shalt
(131)
with
the
Allen
wrench
(screws
make
contact
with
the
surface
of
the
adjusting
shaft).
Set
the
neutral
position
by
moving
the
cam
axially.
If
material
feed
no
longer
occurs,
retighten
the
.forward.
stitch
set-
ting
cam.
Now,
slide
the
."backward".
stitch
setting
cam
(132)
up
to
the
limit
stop
and
tighten.
Mounting
screw
(136)
should
rest
on
the
same
plane
as
the dforward.
stitch
setting
cam.
Finally,
slide
the
setting
ring
to
the
cam and
tighten.
Fig
27
134
135
I
22
133
132
136
I V
0i
]134
Fig.
28
17

Adjusting
buttonhole
without
thread
CAUTION: The
needle
must
not
be
blunt
or
bent,
Check position
of
buttonhole
foot.
t
The
bead
widths
and
bor
tack
widths
are
jW7
controlled
by
the
built-in
carts
and
there-
SW
5_
t
tore
cannot
be
adjusted,
5
Set
zig-Zag
knob
to
posilon
A,
Set
stitch selection
knob
(14)
on
the
first
bar
tack
and
stitch
length
knob
(22)
bet-
ween
positions
.
and
"0
5.Use
raw,
2-ply
cotton-cretonne
for
sewing
material.
place
it under
the
buttonhole
foot
and
start machine.
j37
In
this
position,
feed
of
the
material
must
K
not
occur
if
it
does,
correct
the
adjust-
ment
in
the following
manner
On
forward
feed loosen
locknut
i140)
on
eccentric
screw
(139)
slightly
and
usinlg
a
secondi
fork
wrench
adjust
upwards
until
a
the
work
is no
longer
fed.
If
backward
feed
occurs,
adjust
cam
screw
(139)
in
the
same
manner
but
Fig.
29
downwards
CAUTION:
Retighten check
nit
(140)
wit-
hout
rotating
cam
screw.
Check
second
bar
tack
If
feed
of
the
material
still
138
137
140
138
139
Fig
30
18~~~~~~~~~~~~~~~~~4