Pfaff 3119 Instruction Manual page 29

9 Threading the bobbin case / adjusting the bobbin thread tension
.03
1
5
7
6
Fig. 9 - 03
Insert the bobbin 1 in the bobbin case.
First guide the thread into slot 3 and under spring 4.
Then guide the thread into slot 5.
For purl buttonholes:
Push thread through opening 6.
For flat buttonholes:
Push thread through opening 7.
Trim thread on thread knife 8.
Adjust the thread tension by turning screw 9.
To do so use the tools supplied.
2
When sewing flat buttonholes, the tension of the bobbin thread must be so
high, that the bobbin thread is interlooped on the bottom side of the material.
Setting up
3 4
8
9
9 - 3