ELNA 683 Manuel D'instructions page 58

Needle thread is too
loose.
a
If the needle thread is too
loose and clearly visible on
the underside of the fabric,
decrease either or both
looper thread tensions and/or
increase the needle thread
tension (blue or red).
Upper looper thread is
too loose.
If the upper looper thread
is loose and pulled
b
down to the underside of
the fabric, decrease the
lower looper thread tension
(green) and/or increase the
upper looper thread tension
(yellow).
Lower looper thread is
too loose.
If the lower looper thread is
c
loose and pulled up onto the
top side of the fabric, decrease
the upper looper thread
tension (yellow) and/or
increase the lower looper
thread tension (green).
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