Siruba BH9820, Operation Manual

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adjusted properly.
The needle is too thin. Select needles fit for the
sewing
Upper thread
is not cut off.
The upper cutter is not so sharp Replace a new upper cutter
The pressure is too low to let
upper
Adjust the pressure
The upper cutter can’t catch the
upper
thread.
Install a upper thread bend
needle,
and cut the thread at the stitch
At the last stitch, the upper
cutter
can’t catch the upper thread due
Refer to “Needle-jumping”, try to
avoid the needle from jumping
The position of upper cutter
is
Adjust the position of upper cutter
Bottom thread
is not cut off.
The cutter is not so sharp. Replace a new cutter.
The pressure is too low to let
upper
Adjust the pressure
The position of cutter is improper Adjust the position of the cutter
and
The pressure on cutter for
trimming
Adjust to a proper cutter
pressure
Stitch-missing
at sewing start
Can’t hold bottom thread. Adjust the bottom thread
holder
(configuration 01) or bottom
The leftover part of the upper
thread
Adjust the assistant thread holder.
The released upper thread is far
from
Adjust the amount of released
upper
Cutting function
abnormal
Low pressure on cutting device Adjust the pressure to a proper level
Cutter doesn’t properly connect
with
Polish the surface of cutting hammer
The cutter is not so sharp. Replace a new cutter.
Low thread
density
The tension of upper thread is
so
Adjust the upper thread tension to
a
The tension of bottom thread is
so
Adjust the bottom thread tension to
a
The strength and stroke of take-
up
Adjust the strength and stroke
of