Abstract: Boards that have been separated by a chipless cutting method using an inced blade, are twisted and, in most instances, this twist has to be corrected before boards that have been produced in this manner can be used. An apparatus in which a plurality of pairs of rollers are arranged in tandem withing a main frame is used to do this. Each pair of rollers can be pivotted about the longitudinal axis of the main frame relative to the proceding pair. This forms a board guide channel that extends in the longitudinal direction of the main frame and which is twisted approximately about the longitudinal axis of the main frame. The boards that are to be straightened pass through the board guide channel and are permanently deformed, which compensates for the twist that originally existed in the board.