JUKI MF-7900 Series Engineer's Manual page 27

Adjustment procedures
Loosen setscrew ❸ and move needle bar thread take-up
1.
thread receiver ❶ up or down to adjust the height.
2. When desired to make needle bar thread take-up thread re-
ceiver ❶ work especially on the right needle where loop is hard
to be made, adjust the height of right needle thread receiver ❹
with setscrew ❺ .
Results of Improper adjustment
◦ Since larger thread loops are
formed by raising needle bar
thread take-up receiver ❶ , it is
necessary to adjust the needle
bar thread take-up receiver while
checking the state of thread
loops. The needle thread tension
is also changed according to the
adjustment of the needle bar
thread take-up receiver.
◦ If the needle bar thread take-up
receiver ❶ is excessively raised,
an extra load will be applied to
the needle resulting in needle
breakage. Excessive adjustment
of the needle bar thread take-up
receiver should be avoided.
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