Singer QuantumLock User Manual page 15

Align one piece of medium weight fabric so
that the knife just slightly trims the fabric edge.
Sew.
Align a second piece of medium weight fabric
so that the knife just slightly trims the fabric
edge.
Place the two fabrics, right sides together.
Using a conventional sewing machine, sew a
straight stitch with a ⅝ inch seam.
Press the seam open.
Three-Thread Overlock (narrow) page 14