a two - needle sewing machine includes a machine casing having a sewing head mounting the needles , a work support plate , and a ripping knife supported in the sewing head and working between the needles to form an elongated slot of a braid opening in a cut garment piece . a supporting bar is guided in the machine casing for longitudinal displacement perpendicular to the work support plate , and is rotatable into different angular positions . a single angular cross - section cutting knife is mounted on the supporting bar and serves as a tool for making diverging corner cuts at the opposite ends of the elongated slot . air - operated piston - cylinder actuators are provided to rotate the supporting bar between two positions spaced angularly by 180 °, and to displace the supporting bar longitudinally to effect the diverging corner cuts . the sewing head mounts a sliding foot arrangement for moving the work in a direction opposite to the normal work feeding direction .