Viewed from the
wrong side
Two stitches
are skipped.
8. Double chain stitches are skipped.
Needle height
If the needle is not correct, stitch skipping
Refer to the pertinent Standard Adjustment.
occurs even when the return of the chain
looper is correct.
Needle
The needle is bent or attached with wrong
Replace the bent needle. (Remove the cause
orientation. A DC x1 needle is used.
for the needle bend.) Correct the orientation of
the needle. Use a DC x27 needle (with a better
recess configuration).
Double chain looper
The lower part of the blade point has been
Replace the double chain looper.
deformed, and the blade point fells loops.
Trouble
Case (1)
Case (2)
Check and Corrective measures
Page
7. Upper looer thread stitches are skipped.
Threading
The thread has been entangled with a
See the threading diagram.
thread guide.
(Refer to the Instruction Manual)
Threading has not been done correctly.
Needle height
The needle, if positioned too high or low,
Refer to the related Standard Adjustment
4
may fail to catch the upper looper thread.
Needle
The needle is bent or crushed, in its point.
Replace the needle. At this time, be sure to
eliminate the cause for such needle bend or
needle point crush.
Adjustment of the upper looper.
The height of the blade point is not correct,
Refer to the relevant Standard Adjustment.
4, 14
making the upper looper unable to properly
pass the thread to the needle.
The clearance between the needle and the
back of the upper looper is not correct.
Amount of thread
Excessive upper looper thread is fed,
Slightly lower the looper thread take-up (left)
36
producing stack of thread.
(reduction in distance J), or slightly reduce
distance I to decrease the amount of thread.
Make the upper looper thread guide (right)
(shorter decrease in distance K), to reduce the
amount of thread.
Slightly raise the looper thread take-up (right)
36
(increase in dimension O) to decrease the
amount of thread.
If the thread tension is not enough, increase it.
The needle does not take the
upper looper thread.
The double chain looper tails to
catch needle thread loops.
▼
Right side
Wrong side
Lower
looper
thread
Needle
Upper looper
– 52 –
Needle
Slack of thread
to the next page
Summary of Contents for MO-6700D Series
Page 49: ...45 2 Upper looper components...
