−
12
−
2) Adjusting the thread trimmer cam timing
First, loosen two setscrews (Fig. 12) in the thread
trimmer cam in the order of No. 1 and No. 2, and align
marker dot on the hand wheel with marker dot on the
machine arm. (Fig. 13 (1) and red (2) or green (3) )
Next, pressing thread take-up picker (Fig. 12 (1) ) to
the right, engsage cam and roller, turn cam only with
finger top in the reverse direction as against the rotating
direction of hook driving shaft without turning the hook
driving shaft (arrow mark in Fig. 12). Press the cam to
roller (Fig. 12) at the position where the cam does not
rotate, and tighten setscrews in the cam in the order of
No. 2 and No. 1.
When the cam collar has not been moved, press the
thread trimmer cam to the cam collar and tighten the
setscrews in the order of No. 2 and No. 1.
(1)
(1)
(2)
(3)
3-5 Observing and adjusting the thread trimmer cam timing
1) Proper observing of the thread trimmer cam timing
Thread trimmer cam timing for both cotton and synthetic threads can be easily adjusted by aligning marker dot
on the machine arm with that on the handwheel.
Tilt the machine head, turn the handwheel by hand until the thread take-up lever goes up slightly near the
upper dead point, press thread take-up picker (Fig. 12 (1)) to the right with fingers, and roller enters the cam
groove of thread trimmer cam to engage with each other. At the same state, turn the handwheel in the reverse
direction as against the normal operation of the sewing machine, and there is a position where the sewing
machine does not rotate. At this time, adjust the cam timing so that marker dot (Fig. 13 (1)) of the machine arm
shown in Fig. 13 is aligned with marker dot (Fig. 13 (1)) on the handwheel. This is the cam timing for cotton
thread and synthetic thread.
Thread trimmer cam
Setscrew No. 2
Cam collar
Thread trimmer cam
Turn cam by hand in
this direction.
Roller
Fig. 12
Green
Red
Fig. 13
