5. INSTALLATION
BAS-311F-0, 311F-L, 326F-0
24
5-5. Replacing the bobbin case and threading the thread
CAUTION
If the power switch needs to be left on when carrying out replacing the bobbin, be extremely careful to o bs erve
all safety precautions.
The machine may operate if the foot switch is depressed by mistake, which could result i n injury.
(ex. Continuing sewing from a stopping point)
1. Pull the shuttle race cover (1) forward and then open the c over.
2. Lift the bobbin case latch and remove the bobbin case.
3. Insert a new bobbin into the bobbin case, a nd then pass the thread through the slot (2) and pull it out from the thread
hole (3). Check that the bobbin turns in the direction of the arrow when the thread is pulled at this time.
4. Pass the thread through the lever thread hole (4), and t hen pull out approximately 30 mm of thread.
5-6. Sewing conditions and thread tension

5-6-1. Sewing conditions

BAS-311F-0, 326F-0 BAS-311F-0 BAS-311F-L
Specifications For heavy materials For medium
materials For extra heavy
materials For heavy materials
(denim)
Upper thread # 20 or equivalent # 50 or equivalent # 4 or equivalent # 20 or equivalent
(cotton)
Lower thread # 20 or equivalent # 60 or equivalent # 4 or equivalent # 20 or equivalent
(cotton)
Upper thread
Tension (N) 1.4 - 1.8 1.0 - 1.3 4.5 - 5.0 1.4 - 1.8
Lower thread
Tension (N) 0.2 - 0.3 1.0 - 1.2 0.3 - 0.4
Thread take-up
spring height (mm) 6 - 8 0 6 - 8 mm
Thread take-up
spring tension (N) 0.4 - 0.6 0.15 - 0.35 - 0.4 - 0.6
Pre-tension (N) 0.3 - 0.5 0.1 - 0.3 0.3 - 0.5 0.2 - 0.4
Needle DP X 17 # 21 DP X 5 # 16 DP 17 # 25 DP X 17 # 19
Normal sewing
speed 2000 rpm 2000 rpm 1300 rpm 2000 rpm
The sewing conditions given in the above table may need to be changed depending on the artic le being sewn.
1201S
(1)
30 mm
0110Q 1202S
(3) (2)
(4)