JUKI LU-1510N Engineer's Manual page 75

Troubles
From the previous page
Needle thread is not
caught.
Bobbin thread is not
caught.
To the next page
Causes
From the previous page
Tension of the bobbin
thread is too high.
Knife pressure of the
counter knife is too high.
Initial position of the
m o v i n g
excessively advanced.
Thread is not cut sharply
Stitch skipping at the last
stitch.
C h e c k t h e t h r e a d
trimmer cam timing.
Top end of the moving
knife is broken or has
burrs.
Stroke of the moving
knife is small.
Check the routing of bobbin
thread.
Top end of the moving knife
has broken or been
scratched.
Check the height of moving
knife.
T h r e a d t r i m m i n g i s
performed at the position
where there is no sewing
product.
–71 –
Checking Corrective measures
Adjust the tension of bobbin
thread.
Refer to "(22)-4) Adjusting the
knife pressure".
Refer to "(22)-6) Thread trimmer
k n i f e i s cam timing".
Refer to Causes "Thread cannot
be trimmed" and "Thread remains
uncut after trimming".
Refer to "(7) Needle-to-hook
timing"
Refer to "(22)-6) Thread trimmer
cam timing".
Replace the moving knife with a
new one.
Refer to "(22)-3) Vertical position
of the moving knife".
Correctly thread bobbin thread.
Replace the moving knife with a
new one.
Adjust the height of moving knife.
Perform thread trimming while
pulling sewing product in the feed
direction.