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(22) MF-7500 Series/MF-7900 Series How to use the timing gauge
(Refer to each adjustment item of the Engineer’s Manual for the adjustment procedure)
For MF-7500 Series For MF-7900 Series
(Part No. 40020268) Unit: mm (Part No. 40020269) Unit: mm
Unit: mm
MF-7500 Series
Right needle standard
Needle gauge Returning amount
3.2
4.9
4.0
4.5
4.8
4.1
5.6
3.7
6.4
3.3
MF-7900 Series
Right needle standard
Needle gauge Returning amount
3.2
4.3
4.0
3.9
4.8
3.5
5.6
3.1
6.4
2.7
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
To align
MF-7500 Series and MF-7900 Series are different in the returning
amount even when the needle gauge is the same. Use the gauge on
which MF-7500 Series is stamped for "MF-7700" or that on which MF-
7900 Series is stamped for "MF-7800".
Unit: mm
MF-7500 Series
Top surface of throat plate
standard
Needle gauge Left needle height
5.6
8.5
MF-7900 Series
Top surface of throat plate
standard
Needle gauge Left needle height
5.6
7.8
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.
To align
MF-7500 Series and MF-7900 Series are different in the height. Use the
gauge on which MF-7500 Series is stamped for "MF-7700" or that on
which MF-7900 Series is stamped for "MF-7800". Height of the needle
bar varies in accordance with the needle gauges. For the details, refer to
each adjustment item of the Engineer’s Manual.
