Differential feed on an overlock is a two-part
feed dog which feeds in the fabric at
different ratios. The front part of the feed
dog pushes more or less fabric under the
foot than the rear part of the feed dog is
feeding out. There are two kinds of
differential feed: negative and positive.
Positive feeding may also be used for
gathering or ruffling light to medium weight
woven fabrics. If more gathering is required,
try increasing needle tension dials (blue and
red) to a higher number.
Differential Feed
56
Gathering
Standard Feeding
(1 setting)
Set DF higher than 1 when sewing fabrics which
have a tendency to stretch and create waves
(knits, for example). The looser and stretchier the
fabric, the more the front part of the feed dog
must feed in and the less the rear part of the feed
dog must feed out. Waves are eliminated.
Positive Feeding
(1.5 and 2 setting)
Negative Feeding
(0.5 setting)
The front and rear feed dogs feed the fabric in
and out at the same ratio.
Set DF lower than 1 when sewing sheer
fabrics which tend to pucker. The front part
of the feed dog feeds in less fabric than the
rear part feeds out. The fabric is held taut by
the feed dogs. Puckering is eliminated.
0.5
2
1.75
1.5
1.25