A machine for bending concrete-reinforcing bars and the like is provided with automatic electric sequence control means for performing a desired sequence of bending operations of selected predetermined bending angles. The machine has slip rings of angular extents corresponding to the selectable angles and a contact drum cooperating with these. On the drum are a series of sets of pairs of selectable contacts; each set corresponds to one bending operation and the selected contact pair in the set cooperates with a corresponding slip ring to determine the bending angle for that operation. The drum is stepwise rotated to effect the sequence of operations. To compensate for elastic relaxation of the bar after bending, the bending may be continued beyond the predetermined angle by a further angle determined by measurement of energy absorption, or current consumption, or a time interval, for bending in the elastic range of the bar material. Means for effecting such compensation automatically are described.