White 4050 - LOWER TENSION ADJUSTMENT

[Pag
English
7.
TROUBLE
CHART
PROBLEM
PROBABLE
CAUSE
CORRECTION
Breaking
lower
thread
Thread
not
wound
evenly
on
the
bobbin
or
not
drawn
up
correctly
P15,
P.7,
8
Lower
thread
tension
too tight
P.50, 51
Lint
stuck
in
the
bobbin
case
and inside
the
tension
spring
Remove
lint
and
fluff
with
a
cleaning
brush
Skipping
stitches
Needle
not
fully
inserted
P.18
Needle
bent
P.18
Size
or
type
of
needle
and
thread
not
suitable
for
the
material
P.20
Incorrect
upper
threading
P.7
Too
much
oil
on
the
machine
P.44
Irregular
stitches
Incorrect
size
of
needle
for
the
material
P.20
Upper
thread
tension
too
loose
P.12
Incorrect
lower
tension
P.50,
51
The
material
not
fed
Pattern
selection
dial
not
set
correctly
P.22
correctly
Lint
stuck
on
the
feed
dog
P.4
Noisy
machine
Check
for
thread
in
race,
the
slightest
amount
of
thread
in
P.43
race
may
cause noise
or
binding,
use
material
like
tooth
pick
P.52
or
cotton
swab
to
clean.
Section
7