Although a number of papers exist on the optimization of large-aperture disk amplifiers for use in fusion-laser systems, there is a relative paucity of information on the detailed mechanical design of these devices. In particular, there is little information on their reliability, maintainability, and producibility (RMP). This paper describes two recent designs developed and built by the University of Rochester's Laboratory for Laser Energetics. These 15- 20-cm clear-aperture Nd:glass amplifiers use longitudinal and transverse lamps, respectively, which are water cooled. We describe the design rationale and potential pitfalls. In particular, the disk sizing for a prescribed clear aperture is described. The various laser disk mounting techniques are described and the advantages and disadvantages are compared. Consequences for disk distortion, cladding expansion, cladding survivability, disk stability, and cleanliness are enumerated. The driving requirements for the amplifier frame, which is similar for both devices, are describe. The consequences for cleanliness, stability, and ease of assembly are also described. Finally, the modules containing the flash-lamp arrays are described. These presented the particularly interesting challenge to deliver high voltage and current, cooling water, not degrade pumping efficiency, to be readily serviceable in the event of a lamp failure, and to be cost effective. A working compromise among all of these conflicting requirements was achieved. The module designs, materials used, and the actual performance are described.