Tension Of The Lower Thread (Tension Of The Bobbin Case) - Necchi Supernova Instructions Manual

Fig. 70

- Tension of the lower thread (tension of the bobbin case).

The tension spring No. 20178 in the bobbin case No. D 20176
(see Fig. 70) must place the lower thread under maximum
tension when the bobbin case tension spring screw No. 20179 is
completely tightened. This tension will gradually decrease when
the tension spring screw is loosened. The lower thread must
always be under some ten-sion until the screw No. 20179 is
completely loosened. The tension of the lower thread must
remain uniform for any particular position of the adjusting screw
No. 20179 and must not change while the screw remains in this
position. Fig. 70 shows the bobbin case in a dismantled condition.
D20176
D20172
20176
20181
78
Copyright -2004