To Regulate The Tensions; Tension On The Upper Thread - White 671 Instruction Book

To regulate the tensions
For ordinary stitching, the tension on the upper and lower threads should ba
equal so as to lock both threads in the center of the fabric.
thus:
If the tension on either thread is stronger than on the other, imperfect stitching
will be the result.
If the tension on the upper thread is greater than that on the lower thread.
it will lie straight along the upper surface of the fabric,
thus:
If the tension on the lower thread is greater than that on the upper thread,
the lower thread will lie straight along the under-side of the fabric,
thus :
Tension
'i
the upper thread
The sewing machine will give perfect per
formance when the upper thread tension
is correctly adjusted.
A) The tension on the upper thread be
comes stronger when the tension-dial
is turned in the direction marked
(±). (Fig. 17)
(Fig. 17)
11