Singer class 251 - Needle Thread Take-Up Spring Adjustment; Setting Presser Bar Height

From the library of Superior Sewing Machine & Supply LLC - www.supsew.com
20
ADJUSTMENT
OF
NEEDLE
THREAD
TAKE-UP
SPRING
SETTING
THE
HEIGHT
OF
THE
SPRING:
Thread
the
machine.
Turn
the
machine
pulley
over
toward
operator
until
take-up
lever
reaches
its
lowest
p::)int
and
begins
lo
rise.
0
HIGHER
~
;~~
f\w
DIP
5
'
~
LOWER
LOOSEN
0~
\
R
Q
~
TIGHTEN
MORE
\
PRESSUR~
~
c~.Y~
R
~~Wu,,
s
Fig. 28. Setting
Fig. 29.
Adju,ting
Height
of Spring
Ten,ion
on
Spring
As
take-up
lever
begins
to
rise,
the
needle
thread
is
cost
off
the
hook.
The
HEIGHT
of
the
thread
take-up
spring
Q
should
be
set
so
that
al
this
point
(cast-off)
the
take-up
spring
will
"check"
(show
a
slight
dip)
and
return
to
rest.
later,
when
take-up
lever
approaches
lop
of
stroke,
ii
begins
lo
set
the
stitch,
causing
the
take-up
spring
lo
be
drawn
all
the
way
down.
As
take-up
lever
descends,
the
take-up
spring
will
return
lo
its
highest
point
(rest).
To
adjust
height
of
take-up
spring
Q,
loosen
set
screw
R
and,
by
turning
stud
S,
rotate
entire
take-up
assembly
over
toward
right
to
raise
the
spring
or
over
toward
the
left
to
lower
it.
Securely
tighten
set
screw
R.
NOTE:
Under
certain
conditions
of
tacking,
it
may
be
necessary
to
set
the
take-up
spring
higher
than
it is
otherwise
normally
set.
ADJUSTING TENSION ON
TAKE-UP
SPRING:
The
tension
on
the
thread
take-up
spring
Q
should
be
sufficient
to
ensure
its
action
at
high
speed.
However,
it
should
be
light
enough
to
permit
it
to
be
pulled
all
the
way
down
before
any
thread
is
drawn
through
the
tension
discs.
Before
adjusting,
make
certain
that
set
screw
R is
securely
tightened
so
that
when
stud
S
is
turned,
the
remainder
of
the
assembly
cannot
turn.
Also
make
certain
that
the
thumb
nut
is
in
place
on stud
S,
so
that
stud
may
be
turned
with
screwdriver
without
breaking.
To
adjust
tension on
take-up
spring,
turn
only
the
stud
S
(using
screwdriver
with
blade
large
enough
to
fit
snugly
into
slots
in
stud)
over
toward
right
to increase tension
or
over
toward
left
to
decrease
tension,
as
shown
in
Fig.
29.
NOTE:
The
tension
on
the
take-up
spring
may
require
different
settings
depending
upon
the
size
of
thread
used.
Heavier
thread
requires
more
tension
to
ensure
correct
thread
control.
CAUTION:
Take-up
spring
setting
must
be
checked
each
time
a
different
foot
is
applied
to
machine.
21
TO
SET
THE
PRESSER
BAR
AT
THE
CORRECT
HEIGHT
When
presser
bar
is fully
raised
by
presser
bar
lifter
and
needle
bar
is
at
its
lowest
position,
presser
foot
should
just
clear
bottom
of
needle
bar,
as
shown
in
Fig.
30.
When
presser
foot
rests
squarely
on
throat
plate,
with
feed
dog
below
throat
plate,
there
should
be
a
slight
amount
of
play
between
guide
bracket
T, Fig.
30
and
lifting
bracket
U, Fig.
30.
This will
permit
presser
foot
to
rest
firmly
upon
material.
I I
AT
AT
t
~
I
LOWEST
HIGHEST
~POINT
POINT
-
0
JUST
c.
CLEAR
Fig.
30.
Prener
Bar
Set
al
Correct
Height
To
adjust,
loosen
clamp
screw
V,
Fig.
30
and
raise
or
lower
guide
bracket
T,
as
required.
When
presser
bar
is
set
at
correct
height,
securely
tighten
screw
V.
CAUTION:
Whenever
guide
bracket
has
been
moved
on
presser
bar,
check
take-up
spring
for
correct
setting,
as
instructed
on
page
20.