typical GC6-6, Instruction Book

Page: 17 / 56

31
C
A
B
D
0.05-0.7mm
14
29
C
D
E
2.5mm
1.2 mm
6.1.2 Adjusting rotating hook point timing with needle
(Fig. 29)
Turn the balance wheel to locate needle bar to its
lowest position, and when needle bar lifted again at 2.5mm
from its lowest position, the rotating hook point D should
be coincides with needle center line C, and hook point D
is 1.2 mm above the upper edge E of needle eye.
When adjusting the rotating hook point timing also note
that clearance between notch bottom of needle D and
hook point C must be maintained approx.0.05mm (see Fig.
30)
30
C
D
0.05mm
6.1.3 Removing and installing the rotating hook (Fig. 31)
1) Lift the needle bar to its highest position.
2) Remove the throat plate, take down the needle
and the bobbin case.
3) Loosen rotating hook bobbin case holder position
bracket screw C and take down position bracket .
4) Loosen two set screws D of rotating hook.
5) At this point, the rotating hook can be turned freely
on its shaft, and it can be kept to avoid the collision with
feed dog support as the feed dog support in its highest,
then take down the rotating hook slowly.
6) Installing the rotating hook can be done in reverse
sequence.
6.1.4 Adjusting the clearance between rotating hook
and bobbin case holder position bracket (Fig.31)
The projecting flange of the position bracket A should
be engaged in the notch B of the bobbin case holder, and
maintain a clearance of 0.5-0.7 mm between projecting
flange top and the bottom of notch while installing.