White W2500 Sewing Machine User Manual


 
DIFFERENTIAL
FEED
The
differential
feed
has
two
independent
feed
dogs,
one
front
(A)
and
one
rear
(B).
Each
feed
dog
has
an
individual
feed
mechanism
which
enables
the
feeding
of
material
at
a
different
ratio.
POSITIVE
DIFFERENTIAL
FEED
WHEN
SET
FOR
POSITIVE
DIFFERENTIAL
FEED,
the
front
feed
dog
(A)
makes
a
longer
stroke
than
the
rear
feed
dog
(B).
This
has
the
effect
of
accumulating
material
under
the
presser
foot
to
offset
the
wavering
on
the
fabric.
NEGATIVE
DIFFERENTIAL
FEED
WHEN
SET
FOR
NEGATIVE
DIFFERENTIAL
FEED,
the
front
feed
dog
(A)
makes
a
shorter
stroke
than
the
rear
feed
dog
(B).
This
has
the
effect
of
stretching
material
under
the
presser
foot
to
offset
the
puckering
on
the
fabric.
Illustration
*
I
Differential
feed
dogs
*
II:
Positive
differential
feed
*111:
Negative
differential
feed
B
(
*1
*11
*ffl