Necchi NC-204D Instruction Manual page 66

Darning stitches are sewn from the front of
the presser foot to the back, as shown.
Note
If the fabric does not feed, for example,
because it is too thick, increase the stitch
length.
If the sewing range is too big to sew, then we
suggest you can sew several times (or cross
sew) to get better sewing result.
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