JUKI MO-6700D Series Manual page 13

Adjustment Procedure
1
1) Returning amount of the lower looper
Loosen setscrew
looper to make adjustment of the returning amount.
(Referential information)
1. Radius of lower looper
K
looper is inserted into lower looper support arm
tacts with stopper pin
2. The rocking angle of the lower looper will be 26
1
2) Clearance between the lower looper and the needle
Loosen setscrew
it is temporarily tightened. Then finely adjust the longitudinal position
2
of the looper using fine adjustment screw
Turn fine adjustment screw
from the needle.
Turn the screw counterclockwise to move lower looper
of lower looper support arm
will be 66.9 mm when the lower
and then is fixed.
of lower looper support arm
clockwise to move lower looper
and adjust lower
until it con-
°
.
to the extent that
.
away
closer to it.
– 9 –
Results of Improper Adjustment
o Excessive return of the lower
looper tends to cause stitch
skipping when filament thread is
used.
o Insufficient return of the lower
lopper tends to cause needle
thread stitch skipping when spun
thread is used.
o Excessive clearance will often
cause needle thread stitch
skipping.
o Insufficient clearance will cause
needle breakage due to the con-
tact of the looper with the needle,
or produce scratches on the
blade point of the looper, lead-
ing to needle thread breakage or
other troubles.