SINGER 6211 - Manual (Page 23)

Adjusting stitch length
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.
The tension dial allows you to regulate
the needle thread tension. The correct
tension setting should produce a
smooth even stitch with the top and
bottom threads locking at the corners
of the zig-zag. The top thread may be
visible on the underside of the fabric to
varying degrees, depending on the
thread, fabric, and size of the stitch being
sewn, (1)
Too much tension will produce a tight
stitch causing the fabric to pucker, (2)
To reduce puckering turn the tension
dial to a lower setting. On some fabrics
this may not permit perfect corner
locking of the stitch on the underside
of the fabrid.
Too little tension will cause the stitching
to be loose. In severe cases loops will
form on the underside of the fabric.
Increase tension by turning the dial to
a higher setting: (3)
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