Abstract: The invention is a system and method for printing 3D objects that employs a hydraulic device. The device may comprise a cartridge or container assembly, which may be single-use or disposable. The container assembly may unitarily house a structure such as a piston, a platform, multiple chambers, and a channel, wherein the channel and chambers are fluidly connected and configured to hold enough of a 3D printing material suitable for printing a single 3D object. In exemplary embodiments, moving the piston transfers 3D printing material from one chamber to another chamber in which the platform is situated; radiation from a light engine coupled to the chamber that includes the platform exposes the 3D printing material to a curing light on a surface of the platform or onto a cured layer of the printing material on the platform, in order to build the 3D object on the platform.