SINGER W310 - Manual (Page 17)

(Ci
Upper tension too weak
CONTROLS:
ADJUSTING THE THREAD
TENSIONS
Always adjust the upper thread
tension
with the presser foot
lowered, as the tension is released
when it is raised. To increase the
tension on the upper thread, turn
the tension dial to the right. To
decrease the tension, turn it to the
left. Before adjusting the tension,
make sure that the machine is
threaded correctly. Normal upper
tension is usually between 4 —6 .
The bobbin thread tension seldom
requires adjustment. However,
when the bobbin thread tension has
to be changed, turn the small screw
on the side of the bobbin case
clockwise to tighten and counter­
clockwise to loosen.
When both tensions are properly
balanced, a perfect stitch will be
formed with both threads interlock­
ing in the fabric {A).
When the upper tension is too tight,
the bobbin thread is pulled up over
the upper thread which lays flat on
the fabric (B).
When the upper tension is too
loose, the upper thread forms loops
over the bobbin thread lying flat
on the fabric {C).
When the upper and bobbin thread
tensions are balanced but the fabric
is puckered in sheer fabrics, both
tensions
are too tight. Slightly
loosen both tensions evenly.
It is recommended to adjust the
tension balance with a medium
stitch length. In the case of satin
stitching for buttonholes and
embroidery slightly loosen the
upper thread tension.
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