Abstract: A crimper assembly for crimping a workpiece such as a hose fitting is disclosed. The crimper assembly includes a pair of tie rods of differing diameters which mount a lower stationary die carriage and an upper movable die carriage. A central rod is mounted on the movable carriage and extends through a press bar. A driving force is applied to the central rod by a cylinder in one embodiment and by a tool, such as an impact wrench in another embodiment. Die retainer plates are attached to the carriages and include guide slots. Tongues are provided on flexible die set retainers which are received in the guide slots. A spring biased disconnect plate is slidably attached to the tie rods adjacent the press bar. When the disconnect plate is moved to a disconnect position, the movable carriage can be moved upwardly for access to the flexible die set retainers for changing individual dies.