JUKI IP-100A Engineer's Manual page 29

Adjustment Procedures
1. Hook adjusting mode
1) When performing the hook adjusting, turn ON the power. When the needle
bar is not in UP position, turn the handwheel to bring the needle bar to its UP
position.
2) Press switch 1 for approximately three seconds to display the information
screen.
3) Press 2 to enter the hook adjusting mode.
4) Zigzag patterns of straight stitch and standard zigzag stitch can be selected in
the hook adjusting mode.
Straight stitch
3 : Changeover of straight stitch and standard zigzag stitch can be performed.
4 : Position of stitch base line is set with "+" and "-".
Standard zigzag stitch
5 : Changeover of straight stitch and standard zigzag stitch can be performed.
6 : Zigzag width is set with "+" and "-". (Initial value is set to 8 mm.)
7 : Position of stitch base line is set with "+" and "-".
5) Turn ON/OFF the power to return from the hook adjusting mode to the normal
sewing mode.
* Sewing machine does not work even when the front part of the pedal is
depressed during the hook adjusting mode.
* Needle throwing works by turning the handwheel by hand.
* Needle bar moves when the set value is changed at needle UP position.
(Caution)
1. It is possible for zigzag width and position of the stitch base line
to set up to the width of 10 mm regardless of the max. zigzag width limitation at the time of the hook adjusting mode.
2. When using the hook adjusting mode for the machine to which presser foot, gauge, etc. are attached, be very
careful in performing the adjustment.
2. Adjusting the hook position
™ Adjust the height of the needle bar with engraved marker dot 1 of timing gauge E. At this time, the needle bar is in
its lowest position.
1) After adjusting the height of the needle bar, set the needle to the position of zigzag width "0" and adjust the hook
so that the blade point of the hook is brought to the center of the needle at the height of engraved marker dot 2 of
timing gauge E.
2) At this time, adjust so that the blade point of the hook slightly comes in contact with the needle when the needle guard does
not come is contact with the needle. Then tighten the screw in the hook.
3. Confirmation
1) Confirm that the distance from the top end of needle eyelet to the blade point of the hook is 0.2 to 0.5 mm in case of the
leftmost needle throwing position at the time of max. zigzag width.
2) When zigzag width 10 mm is used or the indented part of the needle is different in shape, re-adjust the height of the needle bar.
4. Adjusting the needle guard
1) Maximize the zigzag width (see the table below). Adjust by bending the needle guard so that the needle does not come in
contact with the blade point of the hook at both the rightmost and left most needle throwing positions. At this time, adjust so that
a clearance of 0 to 0.05 mm is provided between the needle and the blade point of the hook.
2) The needle guard is used so that the blade point of the hook does not come in contact with the needle to prevent the blade
point from damage. When you desire to replace the hook, be sure to adjust the position of the needle guard.
Name of pattern Stitch pattern
Standard zigzag
2-step zigzag
3-step zigzag
T stitch
Pattern 2 (fagoting)
Pattern 4
(Caution)
1. Part No. of the hook for LZ-2290A-SS Series is 22525877. Part No. for LZ-2290A-DS Series is 23557259.
Designate the hook with the part No. when replacing it.
2. When changing the kind or size of the needle, be sure to check the clearance between the needle and
the blade point of the hook.
3. The maximum zigzag width is regulated to 8 mm since the standard gauge is 8 mm at the time of delivery.
Max. zigzag width Name of pattern
10 mm Scallop
10 mm
10 mm Blind stitch
10 mm Custom pattern
10 mm Pattern 1
10 mm Pattern 3
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Results of Improper Adjustment
™ If the timing relation between the
needle and the blade point of the hook
is excessively advanced, smaller
thread loops will be made particularly
when the needle throws to the right or
stitch skipping and thread breakage
will result.
™ If the timing relation between the
needle and the blade point of the hook
is excessively retarded, larger thread
loops will be made particularly when
the needle throws to the left resulting
in tilted thread loops and stitch
skipping.
™ If the needle guard does not come in
contact with the needle, the needle
vibrates when the sewing machine
runs at high speed resulting in thread
breakage and stitch skipping.
™ If the needle comes in contact with the
blade point of the hook, the blade point
will be damaged resulting in an
extraordinary shortened service life of
the hook.
Stitch pattern Max. zigzag width
–
10 mm
10 mm
10 mm
10 mm
10 mm