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(19) MF-7700D/MF-7800D How to use the timing gauge
(Refer to the Engineer’s Manual for the adjustment procedure)
1. Returning amount of the looper
Move the looper to its back end
(extreme right position), fit the slit
of the gauge to the right needle,
and adjust the returning amount so
that the end of the gauge is aligned
with the blade point of the looper.
4.5
4.5 3.7
1.0
4.9
8.5
5
3.3 4.1 4.9
(Part No. 40020268)
Unit: mm
3.9
7.8
3.9
1.0
4.3
8
5
2.7 3.5 4.3
(Part No. 40020269)
Unit: mm
3.1
For MF-7700D
For MF-7800D
Right needle
standard
Needle gauge Returning amount
3.2
4.9
4
4.5
4.8
4.1
5.6
3.7
6.4
3.3
Right needle
standard
3.2
4.3
4
3.9
4.8
3.5
5.6
3.1
6.4
2.7
MF-7800D
MF-7700D
mm
7700D and 7800D are different in the returning amount
even when the needle gauge is the same. Use the gauge
on which 7700 is stamped for 7700 or that on which 7800
is stamped for 7800.
Align
2. Height of the needle bar
Bring the needle bar to the upper
dead point of its stroke, fit the
gauge from the top surface of the
throat plate to the top end of the
left needle, and adjust the height
of the needle bar so that the end
of the gauge is aligned with the tip
of the needle.
7700D and 7800D are different in the height. Use the gauge on which 7700 is stamped for
7700 and that on which 7800 is stamped for 7800. Height of the needle bar varies in accor-
dance with the needle gauges. For the details, refer to the Engineer’s Manual.
Align
MF-7700D Top surface of throat
plate standard
Needle gauge Left needle height
5.6
8.5
mm
MF-7800D Top surface of throat
plate standard
Needle gauge Left needle height
5.6
7.8
mm
3. Spreader
(2) Protruding amount of the spreader
When the spreader travels to its front end
(extreme left position), fit the left needle to
the slit of the gauge, and adjust the lateral
position so that the top end of the thread
guide of the spreader is aligned with the end
of the gauge.
Spreader
Throat plate
Aligh
(3) Clearance between the needle and the
spreader
Insert the gauge between the left needle and
the spreader when the spreader starts to re-
turn from the extreme left position to the right
and comes nearest to the left needle, and
adjust the clearance.
(4) Clearance between the spreader and
the fixed thread guide
Insert the gauge between the spreader and
the fixed thread guide, and adjust the height
of the fixed thread guide.
(5) Clearance between the fixed thread guide
and the needle clamp thread guide
Bring the needle bar to the lowest position
of its stroke, insert two pieces of the gauge
between the fixed thread guide and the
needle clamp thread guide, and adjust the
height of the needle clamp thread guide.
4. Height of the feed dog
Bring the feed dog to its highest posi-
tion, put the gauge from the upper part
of the feed dog and adjust the height.
(1) Height of the spreader
Insert the timing gauge between the top sur-
face of the throat plate and the bottom sur-
face of the spreader.
7700D and 7800D are different in the height.
Use the gauge on which 7700 is stamped
for 7700 and that on which 7800 is stamped
for 7800.
Summary of Contents for MF-7800D Series
Page 64: ...60 5 Adjusting the upper knife stroke A B Standard Adjustment H21...
Page 66: ...62 MEMO...
Page 80: ...76 3 Adjusting the elastic band presser plate 0 5mm Standard Adjustment E10 A A Approx 7 5 mm...
Page 84: ...80 MEMO...
Page 94: ...90 3 Setting of SC 510 2 Change of the setting Type B Type A Standard Adjustment UT25...
Page 114: ...110 MEMO...
Page 118: ...114 2 Installing SC 510 1 Wiring SC 510 Standard Adjustment UT22...
Page 124: ...120 MEMO...
Page 134: ...130 MEMO...
Page 142: ...138 7 Feed timing of the roller A Standard Adjustment PL11 C D B...
