Replacing The Bobbin Thread Slack Preventer Sprlng (For Lh-3568, 3568-7); Stop Of The Needle Bars And Angle Of Corners For Corners Stitching (For Lh-3568, 3568-7) - JUKI LH-3528 Instruction Manual

6-11. Replacing the bobbin thread slack preventer sprlng (For LH-3568, 3568-7)

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6-12. Stop of the needle bars and angle of corners for corners stitching (For LH-3568, 3568-7)

(3/16" gauge)
3 stitches
• If sewing a corner of which angle is 40˚ or less, the thread take-up amount of the
bobbin thread slack preventer spring will be insufficient. In this case, the thread
will remain on the wrong side of the material.
• When performing the operation of changeover of separately driven needle bar,
perform the work after stopping the sewing machine once.
When the operation of changeover is performed at 1,000 rpm or more, break-down
will be caused.)
• When the sewing machine is used as the substitute for 1-needle sewing machine
in the state of separately driven needle bar, break-down of the sewing machine will
be caused. When performing sewing with 1-needle sewing machine, remove one of
two needles and use the sewing machine in the state that two needle bars operate.
2
Groove
1
2
90˚
3 stitches
) Loosen screw 1 and remove bobbin thread
slack preventer spring 2 from the groove on
the bobbin case.
2) Fit bobbin thread slack preventer spring 2
which replaces the removed spring in the
bobbin case through the groove.
3) Fix bobbin thread slack preventer spring 2 in
the bobbin case by tighten screw 1 . At this
time, carefully check the operating range and
tension or the spring.
• Stop of the needle bar
When change lever 1 is moved to position L, the
left-hand needle bar stops, and when it is moved
to position R, the right-hand needle bar stops.
• When returning to 2-needle operation
Press change fixing lever 2 . Change lever 1
returns to the position "0", and the machine
returns to 2-needle sewing.
• Relation between the angle of corners and
stitch length
To perform corner stitching with accuracy, the stitch
length can be determined referring to the table of the
number of stitches by gauges.
However, check whether the stitch length determined
really matches the corner by actually sewing it.
(Example) To sew a correr of 90˚ of angle using
a 3/6" gauge with the stitch length
specified to .6mm, the number of
stiches can be obtained in the following
way. Observe the "90˚" columns on the
table of the number of stitches by stitch
length gauges to search for the column
in which ".6" is indicated. Then, you
can find "3" on the top of the "1.6" lines.
This means the number of stitches is 3.
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