Singer class 251 - Regulating Material Pressure; Setting Needle Bar Height

From the library of Superior Sewing Machine & Supply LLC - www.supsew.com
18
TO REGULATE
THE
PRESSURE
ON
THE
MATERIAL
The
pressure
on
the
material
should
be
as
light
as
possible,
while
still
sufficient
to
insure
proper
feeding.
MORE
PRESSURE
~
LESS~
PRESSURE
Fig. 25.
Regulating
the
Pressure
on
the
Material
Turn
the
thumb
screw,
shown
in
Fig.
25,
toward
the
right
to
increase
or
toward
the
left
to
decrease
the
pressure,
as
required.
TO
SET
THE
NEEDLE
BAR
AT
THE
CORRECT HEIGHT
See
that
the
needle
is
correctly
set
in
the
needle
bar,
as
instructed
on
page
8,
"TO
SET
THE
NEEDLE."
Then
remove
the
face
plate.
The
needle
bar
has
two
timing
marks
near
its
upper
end
(see Fig.
26).
Rotate
the
machine
pulley
over
toward
the
operator
until
the
needle
bar
moves
down
to
its
lowest
position.
The
upper
timing
mark
on
the
needle
bar
should
then
be
even
with
the
lower
end
of
the
needle
bar
bushing,
as
shown
in
Fig. 26.
To
set
the needle
bar
at
the correct height,
loosen
the
clamp
screw
M,
Fig.
26,
and
raise
or
lower
the
needle
bar
as
required.
Then
se-
curely
tighten
the
screw
M.
19
NOTE:
If
the
needle
bar
bushing
N,
Fig.
26
has
been
disturbed,
thus
making
it
impossible to use the
timing
marks,
loosen
needle
bar
bush-
ing
set
screw
P
and
raise
or
lower
the
bushing
N
as
required
to
bring
the
top
of
bushing
flush
with
top
of
machine
casting,
as
shown
in
Fig.
26.
Securely
tighten
set
screw
P.
The
needle
bar
should
then
be
set
at
the
correct
height
as
instructed
at
bottom
of
page
18.
,..-
...
,
p
____
____,;_::1):
'
'
' '
'
'
UPPER
~~~~G~'
/i~N
LOWER
~-M
4
TIMING
\\
MARK
NEEDLE
BAR
n
1
LOWE:/
POINTUt
Fig. 26. Setting
Needle Bar
HOOK
POINT
AT CENTER
OF
NEEDLE
'\
-
TT
~i
1/64"
~1u
..
'v"T
Fig. 27. Needle Bar
Set
at
Correct Height
Re-time
the
hook
as
instructed
on
page
24.
When
the
hook
is
correctly
timed
and
the
needle
bar
is
set
at
the
correct
height
the
top
of
needle
eye
will
be
approximately
l
/64
inch
below
the
point
of
the
hook
at
the
same
time
that
the
hook
point
is
at
the
center
of
the
needle.
See Fig.
27.
When
replacing
the
face
plate,
make
certain
that
the
screw
holes
in
the
face
plate
gasket
are
aligned
with
the
respective
screw
holes
in
the
face
plate,
avoiding
injury
to
the
gasket
and
consequent
oil
leakage.