– 62 –
Trouble
Cause
Corrective measures
8. Thread end of the
1st stitch comes
out on the right
side of the materi-
al.
①
Stitch skipping at the 1st stitch.
②
Needle used and thread used are thick
in terms of the inner diameter of the
intermediate presser.
③
Intermediate presser is not properly
positioned in terms of the needle.
④
The direction of air blower is incorrect.
As a result, needle thread at the tip of
needle cannot be clamped with the disc
presser.
◦
Increase the length of needle thread remaining at
the needle after thread trimming.
◦
Change the current intermediate presser with
another one which has a larger inner diameter.
◦
Adjust the eccentricity between intermediate
presser and needle so that needle enters in the
center of intermediate presser.
◦
Adjust the air-blowing direction of the air blower
according to the direction of sewing so that the
needle thread at the tip of needle can be clamped
with the disc presser.
9. The needle thread
is entangled in the
inner hook holder.
①
The clearance provided between the
inner hook holder and the inner hook is
too small.
◦
Adjust the clearance provided between the inner
hook holder and the inner hook appropriately
according to the thickness of needle thread to be
used.
10. The knotting
section of bobbin
thread at 2nd
stitch at the sew-
ing start appears
on the right side.
①
The bobbin runs idle excessively.
②
Bobbin thread tension is too low.
③
The needle thread tension at 1st stitch is
too high.
◦
Adjust the height of idling prevention spring of the
bobbin case appropriately.
◦
Increase the bobbin thread tension.
◦
Decrease the needle thread tension at 1st stitch.
