SINGER 6217 - Manual (Page 23)

Adjusting stitch iength
Any stitch length setting from 1 to 5 will give
you an open zig-zag stitch.
The higher the number, the more open, or
further apart your stitches will be.
The area between 0 and 1 on the dial is used
for satin stitching, a series of closely spaced
plain zig-zag stitches that form a smooth
satin-like surface.
Needle thread tension
The needle-thread tension dial regulates the
amount of tension on the needle thread and
lets you select just the right setting for your
fabric and thread.
The correct tension setting will produce a
smooth even stitch (1).
Too much tension will produce a tight stitch
(2), causing fabric to pucker. Loosen tension
by turning dial to a lower number.
Too little tension will produce a loose stitch
(3), causing loops in your pattern. Tighten
tension by turning dial to a higher number.
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