Needle-To-Hook Relationship; Height Of The Feed Dog - JUKI DDL-8700B-7 Instruction Manual

21. Needle-to-hook relationship

WARNING :
Be sure to turn the power OFF before the following work in order to prevent personal injury due to
unintentional starting of the sewing machine.
❶
❸
A
B
❷

22. Height of the feed dog

WARNING :
Be sure to turn the power OFF before the following work in order to prevent personal injury due to
unintentional starting of the sewing machine.
❶
A
B
0.04 to 0.1 mm
❹
❺
a
0.75 to 0.85 mm
❷
Adjust the timing between the needle and
the hook as follows :
1) Turn the handwheel to bright the needle bar
down to the lowest point of its stroke, and loosen
setscrew ❶.
Adjusting the needle bar height.
2) Align marker line A on needle bar ❷ with the
bottom end of needle bar lower bushing ❸, then
tighten setscrew ❶.
Adjusting position of the hook a.
3) Loosen the three hook setscrews, turn the
handwheel and align marker line B on ascending
needle bar ❷ with the bottom end of needle bar
lower bushing ❸.
4) After making the adjustments mentioned in the
above steps, align hook blade point ❺ with the
center of needle ❹. Provide a clearance of 0.04
mm to 0.1 mm (reference value) between the
needle and the hook, then securely tighten set-
screws in the hook.
If the clearance between the blade point
of hook and the needle is smaller than the
specified value, the blade point of hook
will be damaged. If the clearance is larg-
er, stitch skipping will result.
To adjust the height of the feed dog :
1) Loosen screw ❷ of crank ❶.
2) Move the feed bar up or down to make adjust-
ment.
3) Securely tighten screw ❷.
If the clamping pressure is insufficient,
the motion of the forked portion becomes
heavy.
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