A two-position, quick-change hacksaw consists of a back member, handle structure adjacent a rearward end portion of the back member, and a swing arm adjacent the forward end. The free end of the swing arm and the forward end portion of the back member have coplanar blade-engaging elements thereon which serve to engage the forward end of the blade and which are commonly disposed on an arc that circumscribes a third coplanar blade-engaging element disposed on a coupling block of a tensioning mechanism for mounting the rearward end of the blade. Two coplanar sets of transversely paired engagement elements enable mounting of the blade both in a plane parallel to a medial plane of the frame and also in a plane disposed at a substantial angle thereto. In one configuration, with the swing arm in its inoperative position, the saw is adapted for cutting within a relatively confined space; with the swing arm in its operative position the saw is configured for cutting within a relatively unconfined space.