UnionSpecial 398 Classic Series Setup guide

CATALOG
NO.
WH398M
First
Edition
STYLES
398-21
398-22
398-23
398-24
398-25
398-26
398-27
398-28
398-29
Adjusting instructions and
illustrated
parts list
—
ii
U
398
Classic
Series
- Safety
stitch
machines
with
Pushbutton stitch
length
change
I
Finest Quality
Zua
Equipment
From the library of: Superior Sewing Machine & Supply LLC

CATALOG
NO.
WH398M
ADJUSTING INSTRUCTIONS
AND
ILLUSTRATED
PARTS LIST FOR
398
CLASSIC
SERIES
- SAFETY STITCH
MACHINES
WITH
PUSHBUTTON
STITCH
LENGTH
CHANGE
STYLES
398-21 398-24
398-27
398-22
398-25 398-28
398-23
398-26
398-29
First Edition
Copyright
1982
By
Union
Special Corporation
Rights
Reserved in
All Countries
Printed in
U.S.A.
July,
1982
2
From the library of: Superior Sewing Machine & Supply LLC

CLASS
DESCRIPTION
Small
frame,
high
speed,
high
capacity,
differential
feed,
vertical
needle,
Safety
Stitch
machines.
The
needle
drive
mechanism
moves two
straight
needles
in
a
vertical
plane.
Two
independent
rows
of
stitching
are
produced
-
“Double-Lock”
stitch
at
the
left
needle
and
two
or
three
thread
overseaming
stitch
at
the
right
needle.
Machines
include
fabric
trimming
mechanism,
adjustable
looper
avoid
motion,
fully
enclosed
automatic
lubrication.
TECHNICAL
DATA
STITCH
AND
SEAM
TYPE
Specification
516-SSa-2
Spreader
furnished
for
conversion
to
Specification
515—SSa-2
FEED
SYSTEM
Main
and
differential
feed
mechanisms.
Push
button
stitch
length
adjustment
with
independent
thumbscrew
control
for
differential
feed
MAXIMUM
SPEED
5500
R.P.M.
(Depending
on
operation)
LUBRICATION
Enclosed
automatic
splash
system
with
oil
return
pump
NEEDLE
GAUGE
See
machine
styles
(Seam
width)
NEEDLE
GAUGE
EXPLANATION.
Example:
On
Style
398-27
the
12
3/16
is
gauge
of
machine.
The
12
indicates
the
distance
between
needles
graduated
in
1/64
increments,
thus
12
is
12/64
or
3/16 inch
between
needles.
The
fraction
3/16
represents
the
width
of
overedge
seam.
The
total
seam
width
is
the
sum
of
the
two
figures,
i.e.,
3/16
+
3/16
or
total
seam
width
of
3/8
inch.
MACHINE
STYLES
398-21
(8-1/8
Ga.)
For
seaming
light
to
medium
weight
fabrics.
Short,
narrow
presser
foot
with
matiching
feeds
and
throat plate
allow
stitching
on
short
radius
curves.
Typical
application
-
setting
sleeves
and
side
seaming
work
shirts,
robes
and
pajamas.
398-22
(8-3/16
Ga.)
398-23
(12-3/16
Ga.) General
purpose
machine
for
seaming
light
to
heavy
weight
fabric.
Design
of
sewing
parts
allows
machine
to
be
used
on
a
variety
of
gar
ments
ranging
from
shirts
and
blouses
to
women’s
sportwear
and
jackets.
398-24
(8-3/16
Ga.)
Same
as
Style
398-22
except
fitted
with
narrow
tractor
type
presser
foot
and
related
sewing
parts
for
crossing
heavy
seams.
398-25
Same
as
Style
398—24
except
12—3/16
gauge.
398-26
(5-1/8
Ga.)
398-27
(12-3/16
Ga.)
For
seaming
medium
to
heavy
weight
fabrics.
Typical
applica
tion
-
assembling
and
seaming
operations
on
jeans,
work
clothing,
jackets
and
women’s
sportwear.
3
From the library of: Superior Sewing Machine & Supply LLC

MACHINE
STYLES
(Continued)
398-28
Same
as
Style
398-27
except
fitted
with
tractor
type
presser
foot
and
related
sewing
parts
for
crossing
heavy
seams.
398-29
Same
as
Style
398-21
except
12-3/16
gauge.
NOTE:
All
machine
styles
listed
can
be
furnished
with
“AIR-KLIPP’
vacuum
type
chain
cutter.
IDENTIFICATION
OF
MACHINES
Each
UNION
SPECIAL
machine
carries
a
style
number,
which
on
this
class
machine
is
stamped
in
the
style
plate
located
to
the
right
rear
of
machine.
The
serial
number
is
stamped
on
extension
of
casting
at
right
rear
base
of
machi
ne.
LUBRICATION
Oil
capacity
of
Class
398
is
eight
ounces.
Use
a
straight
mineral
oil
with
a
Saybolt
viscosity
of
90
to
125
seconds
at
100
degrees
F.
This
is
equivalent
to
Union
Special
Corporation
Specification
No.
175.
Machine
is
filled
with
oil
at
spring
cap
under
top
cover
or
at
oil
filler
screw
between
tension
disc
support
and
top
cover.
Before
operating,
check
oil
level
at
sight
gauge
on
front
of
machine.
When
proper
oil
level
is
reached,
red
bulb
on
oil
level
indicator
will
register
between
red
gauge
lines.
To
drain
oil
remove
magnetic
plug
on
back
of
machine
near
bottom
edge
of
base.
Clean magnetic
plug
of
any
metallic
material
that
may
have
accumulated
in
crankcase.
Oil must
be
changed
periodically
to
minimize
wear.
THREADING
Be
sure
machine
is
threaded
properly
according to
threading
diagram
Fig.
1,
for
five
thread
machines
or
Fig.
1A,
for
four
thread
machines.
THREADING
DIAGRAMS
Before
threading
machine;
unlock
presser
foot
release
bushing,swing
presser
arm
and
cloth
plate
out of
position;
pull
upper
looper
thread
tube
up
for
five
threads.
Turn
handwheel
in
operating
direction
until
needles
are
at
highest
position.
Thread
tweezers
No.
660-272
and
threading
wire
No.
39899
A
are
furnished
with
machine
to
aid
in
threading.
Thread
machine
in
sequence
as
shown
in
Fig.
1;
(1) lower
overedge
looper
thread,
(2)
401
looper
thread,
(3) upper
overedge
looper
thread,
(4)
rear
needle
thread
and
(5)
front
needle
thread.
Push
upper
looper
thread
tube
down.
Thread machine
in
sequence
as
shown
in
Fig.
1A;
(1) overedge
looper
thread,
(2)
401
looper
thread,
(3)
rear
needle
thread
and
(4)
front
needle
thread.
4
From the library of: Superior Sewing Machine & Supply LLC

Fig.
1
5
TUBE
UP
From the library of: Superior Sewing Machine & Supply LLC

TURN
TO RELEASE
PRESSER
ARM
Fig.
1A
6
From the library of: Superior Sewing Machine & Supply LLC

-
-
ADJUSTING
iNSTRUCTIONS
NOTE:
Instructions
stating
direction
or
location,
such as
right,
left,
front
or
rear
of
machine;
are
given
relat
ive
to
operator’s
position
at
the
machine.
The
handwheel
rotates
clockwise,
in
operating
direction;
when
viewed
from
the
right
end
of
machine.
EXAMINE
NEEDLES
TO
ASSURE PROPER
TYPE
AND
SIZE
ARE
BEING
USED
(EXAMPLE:
120
GS-090/036).
THE
FOLLOWING
CHECKS
RE
LATED
TO
NEEDLES
ARE
IMPORTANT
FOR
SUCCESS
FUL
OPERATION.
IMMEDIATELY REPLACE
AND
DIS
CARD
DEFECTIVE NEEDLES.
-
Roll
the
needle
over
a
flat
surface
to
check
straightness.
If
the
needle
is
bent
it
will
wobble;
as
shown
(A,
Fig.
2).
-
Use
the
thumbnail
test
to
check
for
bluntness
as
shown
(B,
Fig.
2).
-
Check
for
any
sharpness
around
the
eye and
grooves
of
the
bottom
of
the
eye!
Seesaw
the
thread
through
for
a quick
sharp
it
will
cut
the
thread;
as
shown
(C,
Fig.
2).
-
Make
sure
the
needles
are
all
the
way
up
in
needle
holder
with the
spot
or
scarf
to the
rear;
as
shown
(D,
Fig.
2).
Machines
shipped
from
the
factory
are
sewn
off
using
needles
listed:
Machine
Style
Type
and
Size
398-21,
398-22,
398-23, 398-24, 398-25, 398-26,
398-29
120
GS-090/036
398-27,
398-28
120
GAS-125/049
making
adjustments
involving
the
needles,
loopers
or
needle
guards,
use
new
needles
of
correct
type
and
size.
SEE
FOLLOWING
CHART
FOR
DESCRIPTIONS
AND
SIZES
OF
NEEDLES
AVAILABLE
FOR
CLASS
398
MACHINES.
____________
Description
_______________
Round
shank,
round
point,
set
point,
extra
080/032,
short,
double
groove,
struck
groove,
ball
100/040,
eye,
spotted,
rounded
scarf,
with
3/64
125/049,
inch
(1.2mm)
radius
at
scarf,
chromium
plated.
Same
as
Type 120
GS
except
it
has
a
modi-
110/044, 125/049,
fled
point
140-/054.
Fig.
2
and
hooks
on
the
tip
of the
needle;
needle.
Don’t
forget
the
check.
If
the
eye
is
and
positioned
correctly
NOTE:
Before
always
Needle
Type
120
GS
120
GAS
Size
Available
075/029,
090/036,
110/044,
140/054.
7
From the library of: Superior Sewing Machine & Supply LLC

Needle
Type
Description
Sizes
Available
120
GFS
Same
as
Type
120
GS
except
it
has
a
reduced 110/044,
125/049.
eye
and
groove,
120 GHS
Same
as
Type
120
GS
except
it
has
a
thin
ball
075/029, 080/032,
point.
090/036,
100/040,
110/044,
125/049,
140/054.
120 GKS
Same
as Type
120 GHS
except
it
has an
over-
075/029,
080/032,
size ball
eye.
090/036, 100/040,
110/044.
To
have
needle
orders
promptly
and
accura
tely
filled,
an
empty
package,
a
sample
needle,
or
type
and
size
number
should
be
forwarded.Use
description
on
label.
A
complete
order
would
read:
“1000
Needles,
Type
120
GS,Size
090/036”.
NEEDLE
REPLACEMENT
To
replace
needles,
turn
handwheel
in
oper
ating
direction until
needles
reach
highest
position.
Rotate
presser
foot
release
lever
(A,
Fig.
3)
counterclockwise
and
swing
presser
foot
(B)
to
the
left.
Loosen
screws
(C)
and
remove
needles.
Insert
new
needles
against
stop
in
holder
with
scarf
of
needle
positioned
to
the
rear;
tighten
screws
(C).
Swing
presser
foot
(B)
into
position
and
lock
presser
foot
release
lever
(A).
NEEDLE ALIGNMENT
Needle
must
center
in
needle
slots
of
throat
plate
(left
to
right)
as
shown
in
Fig.4.
If
adjustment
is
required,
loosen
screws
(A,
Fig.
5)
and
needle
lever
binder
screw
(A,
Fig.
6).
Align
needles
to
center
in
throat
plate
needle
slots
by
turning
eccentric
needle
head
guide
bar
(B,
Fig.
5).
Position
needle
lever
to
left
or
right
on
its
cross
shaft
to
correspond
with
the
repositioning
of
eccentric
guide
bar.
Manually
move
needle
head
(C)
up
and
down
several
times to
ensure
that
the
needle
lever
aligns
with
the
needle
head.Tight
en
screws
(A).
Temporarily
tighten
screw
(A,
Fig.
6) and
proceed
to
needle
height
ad
justment.
NEEDLES
ARE
CENTERED
LEFT
TO RIGHT
Fig.
4
—C
Fig.
5
8
From the library of: Superior Sewing Machine & Supply LLC

NEEDLE
HEIGHT
Rotate
handwheel
in
operating
direction
until
needles are
at
highest
position.
Speci
fied
height
is
17/32
inch
(13.5mm)
from
point
(tip)
of
needles
to
top
of
throat
plate
as
shown
in
Fig.
7.
If
adjustment
is
required,
loosen
binder
screw
(A,
Fig.
6)
and
position
needle
lever
(B)
up
or
down
as
required
to attain
specifi
ed
dimension.
Tighten
screw
(A,
Fig.
6).
Ro
tate
handwheel
in
operating
direction
and
check
for
binds
in
needle
head
assembly.
Should
a
bind
exist,
refer
to
NEEDLE
ALIGN
MENT.
Needle
height
gauge
No.
21227
DD
can
be
used
by
placing
it
on
top
of
throat plate
and
rotate
handwheel
to
bring
needle
head
down
so
its
bottom
rests
on proper
step of
gauge
AT
BOTTOM OF
DOWNSTROKE.
You
will
note
two
levels
on
gauge;
upper
step
is
for
these
machines
re
quiring
17/32
inch
(13.5mm)
needle
height,
while
the
lower
step
is
used
for
other
machine
styles
requiring
a
7/16
inch
(11.1mm)
setting.
PRIOR
TO
MAKING THE
FOLLOWING
ADJUSTMENTS,
RE
MOVE
CLOTH
PLATE,
FABRIC
GUARD,
CHIP
GUARD,
UPPER
KNIFE,
LOWER
KNIFE,MAIN
AND
DIFFERENTIAL
FEEDS.
CLOTH
PLATE
To
remove
cloth
plate
(A,
Fig.
8) loosen
screw
(B)
and
lift
upward
with
stud
(C)
and
screw
(D)
assembled.
Before
replacing,
tighten
screw
(D)
while
holding
stud
(C)until
all
end
play
is
removed.
Cloth
plate
must
be
allowed
to
swing
open,
so
do
not
over
tighten
screw
(D).
Assemble
cloth
plate
to
machine
by
inserting
stud
(C)
with
flat
and
“V’
notch
to
rear,
into
hole
in
bed
casting.
Tighten
screw
(B)
to
press
“V’
notch
of
stud
(C)
against
screw
(D).
This
locks
screw
CD)
and
stud
(C)
in
position
and
allows
cloth
plate
to
swing
open.
Fig.
6
lTII
I
17/32 inch
••
(13.5mm)
1
Fig.
7
Fig.
8
9
From the library of: Superior Sewing Machine & Supply LLC

LOWER
OVEREDGE
LOOPER
PRIOR
TO
CHECKING
LOOPER
ADJUSTMENT,
REMOVE
FRONT
AND
REAR
NEEDLE GUARDS.
LOOPER
GAUGE
-
With
looper
(A,
Fig.
9)
at ex
treme
left
position,
distance
from
looper
point
to
centerline
of
rear
needle
should
be
3/32
inch
(2.4mm)
as
shown
in
Fig.
9.
PRIOR
TO
ADJUSTING LOOPER,
POSITION
UPPER
LOOPER/SPREADER
UP
AND
AWAY
FROM LOWER
LOOPER.
Rotate
handwheel
to
position
looper
at
ex
treme
right
end
of
travel
and
loosen
clamp
nut
(B,
Fig.
9).
Rotate
handwheel
to
position
looper
at
extreme
left
end
of travel
and
set
looper
gauge
by
adjusting
looper
in
or out of
looper
shaft
(C).
Rotate
handwheel
and po
sition
looper
into
scarf
of
rear
needle
and
set
looper
point
to
touch
but
NOT
deflect
needle.
Tighten
clamp
nut
(B)
securely
and
recheck
looper
gauge.
REAR
OVEREDGE
NEEDLE
GUARD
Remove
spring
from
inside
of
lower
knife
holder
(A,
Fig.
10)
and
assemble
lower
knife
holder
into
throat
plate
support
block.
Re
place
rear
needle
guard
(B)
using
screw
(C)
with
front
edge
of
guard
centered
in
slot
of
knife
holder
(A)
as
shown.
Tighten
screw
(C)
temporarily
to
hold guard
in
position
yet
allows
it to
be moved.
Rotate
handwheel
in
operating
direction
so
the
lower
overedge
looper
(D)
moves
from
the
extreme
left
po
sition
into
the
scarf
of
rear
needle.
Move
guard
(B)
forward
until
the
front
guarding
surface
contacts
the
needle
but
does
NOT
de
flect
it.
Set
guard
as
low
as
possible
so
that
it
will
not
interfere
with
needle
thread
as loop
is formed
to
rear
of
needle.
Tighten
screw
(C)
securely.
Guard
should
not
inter
fere
with
lower
knife
holder
movement
or
con
tact
lower
overedge
looper
at
any
point.
FRONT OVEREDGE
NEEDLE
GUARD
Assemble
front
overedge
needle
guard
(E,
Fig.
10)
to
throat
plate
support
using
screw
(F).
Rotate
handwheel
in operating
direction
to
position
needle
at bottom
of
stroke.
Set
guard
to needle
with
minimum
clearance
-
approximately
.004
inch
(.10mm).
Tighten
screw
(F)
securely.
DO
NOT
PINCH
NEEDLE
BETWEEN
FRONT
AND
REAR
GUARDS.
Fig.
9
Fig.
10
Fig.
11
10
From the library of: Superior Sewing Machine & Supply LLC