JUKI IP-100A Engineer's Manual page 15

Adjustment Procedures
[Feed "0" adjustment]
1) Set the stitch length dial at "0".
2) Loosen screw 1, and align the timing mark on the feed crank stud
with that on the feed crank stud support.
(The position of the timing mark differs with models.)Insert a sheet of
paper between the throat plate and the presser foot, turn the
handwheel by hand and check that the needle entry points are the
same. If the points are not the same, perform again fine adjustment.
(Fine adjustment is necessary since the marks are standard.)
3) When loosening screw 1, confirm that there is no axial play at the
feed converting arm A (asm.) and tighten screw 1.
[Normal feed adjustment]
4) Set the stitch length dial at the maximum value of the gauge to be
used.
Max. normal feed amount
of the mechanism
* Normal feed is regulated to 2 mm at the time of delivery.
5) Loosen screw 2, make the feed adjusting link come in contact with
the screw and tighten screw 2.
[Reverse feed adjustment]
6) Loosen screw 3, pushing the feed lever down to make the sewing
machine enter the reverse feed stitching mode, press reverse feed
amount regulation metal fitting against the projecting section of the
reverse feed adjusting link B. Now, tighten screw 3. (Set the
condensation stitch length adjusting dial to the maximum value on
the scale.)
Max. reverse feed amount
of the mechanism
* Reverse feed is regulated to 2 mm at the time of delivery.
7) To decrease the reverse feed stitching length for fastening stitching,
use the condensation stitching function. (Refer to "Adjusting the
condensation stitching mechanism" in the Instruction Manual for the
LZ-2290A Series.)
8) When the ratio of sewing length (as many as 10 stitches) of normal
and reverse feed is approximately 90% in case of straight stitch feed
amount of 2 mm, the adjustment is OK.
LZ-2290A-SS, A-DS=5 mm
LZ-2290A-SU, A-DU=2.5 mm
LZ-2290A-SS, A-DS=4 mm
LZ-2290A-SU, A-DU=2.5 mm
11
−
Results of Improper Adjustment
™ If the timing marks are not aligned
with each other, the actual feed
amount will be different from the
feed amount specified on the stitch
length dial.
™ If the timing marks greatly separate
from each other, the normal or
reverse feed amount will be
increased causing the feed dog to
come in contact with thread
trimming counter knife. (In case of
thread trimming)
−
Normal feed → large
Reverse feed → small
Nomal feed → small
Reverse feed → large