A roll forming apparatus comprises a plurality of driving roll stands and a plurality of drivingless roll stands, wherein the drivingless roll forming stand comprises an upper and a lower roll units and side roll units arranged around a central through-hole of a plate member supported by a supporting post. Each of the roll forming stands is adapted for automatically positioning each of the rolls associated therewith to preset positions for bending operation. The plate member is rotatable about the axis of the central hole, and a transverse slide table fixedly mounting the supporting post is transversely movable to the axis. Molding laces for cars are roll formed by bending a strip during travelling through a series of these adjusted roll stands.
