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3-6. Adjustment of the wiper spring
Wiper spring
retains the needle thread after
thread trimming in between wiper
and the wiper
spring. Correct properly the tension of wiper spring
so that the tension at that time becomes 0.2 to 0.3N
(a little higher tension than that of the bobbin thread
coming out of the bobbin case).
If the retaining of the needle thread is ex-
cessive, the thread may protrude from the
upper side of the button.
WARNING :
Turn OFF the power before starting the work so as to prevent accidents caused by abrupt start of the
sewing machine.
3-5. Adjustment of the pressure of the work clamp unit
The pressure of the work clamp unit should be minimized as long as the material does not warp during
sewing. Loosen adjusting screw
and turn adjusting screw
to obtain the aforementioned pressure.
WARNING :
Turn OFF the power before starting the work so as to prevent accidents caused by abrupt start of the
sewing machine.