JUKI LK-1910 Engineer's Manual page 43

Adjustment Procedures
1) Adjust the position of bobbin winder driving wheel 1 so that
the clearance provided between bobbin winder driving wheel
1 and arm cover installing face 2 should be 10.5 mm, and
tighten setscrews 3 (2 places).
Adjustment Procedures
1) When joining presser plate 1 to presser shaft 2, put washer
4 between the presser plate and oval counter-sunk screw 3.
Adjust the number of pieces of washer 4 so that there is no
difference in level between oval counter-sunk screw 3 and
the bottom face of presser plate 1 after tightening the screw.
Results of Improper Adjustment
™ If the clearance is small, it will
cause worn-out of the bobbin
thread winder components or
seizure.
™ If the clearance is excessive, due
to slipping of the bobbin thread
winder, the worn-out will occur.
Results of Improper Adjustment
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