Replacing The Bobbin Thread Slack Preventer Spring (For Lh-3568A, 3568A-7, 3588A And 3588A-7); Stop Of The Needle Bars And Angle Of Corners For Corners Stitching (For Lh-3568A, 3568A-7, 3588A And 3588A-7) - JUKI LH-3500A series Instruction Manual

6-12. Replacing the bobbin thread slack preventer spring
(For LH-3568A, 3568A-7, 3588A and 3588A-7)
1
6-13. Stop of the needle bars and angle of corners for corners stitching
(For LH-3568A, 3568A-7, 3588A and 3588A-7)
2
(3/16" gauge)
90˚
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 sti/min 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 per-
forming 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
3 stitches
) Loosen screw 1 and remove bobbn thread
slack preventer sprng 2 from the groove on the
bobbn case.
2) Ft bobbn thread slack preventer sprng 2 whch
replaces the removed sprng n the bobbn case
through the groove.
3) Fx bobbn thread slack preventer sprng 2 n
the bobbn case by tghten screw 1 . At ths tme,
carefully check the operatng range and tenson
or the sprng.
• Stop of the needle bar
When change lever 1 s moved to poston L, the
left-hand needle bar stops, and when t s moved to
poston R, the rght-hand needle bar stops.
• When returning to 2-needle operation
Press change fixing lever 2 . Change lever 1 re-
turns to the poston "0", and the machne returns to
2-needle sewng.
• Relation between the angle of corners and
stitch length
To perform corner sttchng wth accuracy, the sttch
length can be determned referrng to the table of the
number of sttches by gauges.
However, check whether the sttch length determned
really matches the corner by actually sewng t.
(Example)
To sew a correr of 90˚ of angle using a 3/16" gauge
with the stitch length specified to 1.6mm, the number
of stches can be obtaned n the followng way. Ob-
serve the "90˚" columns on the table of the number
of sttches by sttch length gauges to search for the
column n whch ".6�" s ndcated. Then, you can
find "3" on the top of the "1.6" lines. This means the
number of sttches s 3.
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