Table of Contents
Advertisement
7-5. Replacing the bobbin case and threading the thread
Turn off the power switch before removing and replacing the bobbin case, otherwise the machine may
operate if the foot switch is depressed by mistake and serious injury could result.
Pull the shuttle race cover q toward
you to open it.
7-6 . Thread tension reference guide
Thread
Upper thread tension (N)
Lower thread tension (N)
Thread take-up spring height
(mm)
7-6-1 . Lower thread tension
weaker stronger
q
Adjust the thread tension to the weakest possible tension
by turning the thread tension nut q until the bobbin case
will not drop by its own weight while the thread end com-
ing out of the bobbin case is held.
CAUTION
e
q
Insert a new bobbin into the bobbin
case, and then pass the thread through
the slot w and pull it out from the
thread hole e. Check that the bobbin
turns in the direction of the arrow when
the thread is pulled at this time.
#60 or equivalent
0.7 - 1.3
0.3 - 0.4
6 - 8
LK3-B448E MARK
w
r
Pass the thread through the lever
thread hole r, and then pull out ap-
proximately 30 mm of thread.
Thread take-up spring tension
(mm)
Pre-tension (N)
Needle
7-6-2 . Upper thread tension
Turn the tension nut q (main tension) to adjust the ten-
sion as appropriate for the material being sewn.
Furthermore, turn the thread nut w (sub-tension) to ad-
just the remaining length of upper thread to 35 - 40 mm
when the thread take-up lever is not used.
II
/BA-16
7. Correct use
30mm
0.4 - 0.6
0.1 - 0.3
TQ
1#12
w
Stronger
Weaker
Stronger
Weaker
q
31
Advertisement
Table of Contents
