Upper Thread Tension; Adjustment Of Upper Thread Tension With A Weight - Bernina activa 125 Service Manual

Adjustment of upper thread tension with a weight

Standard:
Test thread Mettler white (BW Ne 60/2 resp. NM 43.1/2).
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Thread the machine including the take-up lever.
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Bring the take-up lever/needle bar to the highest positi-
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on.
Lower the presser foot.
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Turn the tension adjustment dial until the red mark is in
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line with the mark on the top cover.
Draw off approx. 30cm of thread from the bobbin.
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Using the weight 93 g (85 g + 8 g) wrapped around the
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thread at the take-up lever side, check the upper tensi-
on.
The weight of 85 g must not move down.
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Attach the extra magnetical weight of 8 g. The weight
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Basic adjustment of the upper thread tension
Thread the machine up with the inspection thread inclu-
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ding the take-up lever and affix the control weight.
Attention: The thread must be also threaded through the
thread guide.
Use as a control thread (BW Ne 60/2 resp. NM 43 1/2)
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Mettler white.
Inspect the bobbin case tension against the correct
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values (see basic adjustment of bobbin case tension).
Turn the adjustment dial until the red marker is in line
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with the marking on the housing.
Sew off a sample stitch (running stitch).
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Correction:
Turn the adjustment dial accordingly.
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Press the locking lever 112 down the dial is now free.
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Turn the dial until the red mark is in line with the marker
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of the housing.
Release the locking lever 112 into the locking position.
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must now move down slowly.
Correction:
See correction basic adjustment.
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112
43