Singer 1640 - Page 33

PROBLEMS
—
and
PROBABLE
CAUSES
Section
9
Problem
Probable
Cause
Correction
If
Machine
Thread
or lint
in
Binds
raceway
See
instruction,
page
28.
Skipping
Bent
needle
Discard
and
replace.
Stitches
Needle
placed
in-
See
instruction
page
8.
correctly
in
clamp
Too
fine
a
needle
See
needle
and
thread
chart,
for thread
being
used
page
7
Irregular
Upper
thread
tension
Stitches
too
loose
Tighten
upper
tension.
See
threading
instruction,
Improper
threading
page 12.
Bobbin
not
wound
Rewind
bobbin,
page
TO
evenly
Uneven
Stitches
Pulling
or
holding
Avoid
pulling
or
holding
material
material,
just
guide
it.
Not
enough
tension
Increase
tension.
on
upper
thread
Poor
quality
thread
Try
different
thread.
Needle
too
fine for
See
needle
and
thread
chart,
thread
being
used
page
7.
Refer
to
threading
instructions.
Upper
Thread
Improperly
threaded
Breaking
See
page
12.
Loosen
tension
on
upper
thread
Too
much
tension
by
turning
thread
tension
dial
to
lower
number.
Starting
with take-up
Always
start
sewing
with
take
in
incorrect
position
up
lever in
highest
position.
Improper
setting
of
Refer
to
needle
setting
in-
needle
struction.
See
page
8.
Bent
needle
or
eye
of
Insert
new
needle.
needle
too
sharp
Bent
or
blunt
needle
Insert
new
needle.
See
tension
adjustment
Material
Tensions
too
tight
Puckering
page
15
and
16.
Dull
needle
Insert
new
needle.
Stitch
length
too
long
Reduce
stitch
length.
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