In a previous paper [Y. L. Hua, T. X. Yu and S. R. Reid, Double hinge modes in the dynamic response of plastic cantilever beams subjected to step loading. Int. J. Impact Engng 7, 401-413 (1988)] double hinge mechanisms were shown to satisfy all the necessary equations for the initial deformation mechanism of a range of bent cantilevers subjected to an out-of-plane tip force. The present study examines the transient behaviour of such mechanisms when the cantilever is subjected to a force pulse of finite duration. The change in the mechanism as the hinges travel and the partitioning of the dissipation of the input energy are described and compared with the behaviour of a straight cantilever subjected to a force pulse at its tip.