My printer is a behemoth of a printer compared to Mendel and Darwin. The printer stands just over 4 feet tall 26 inches deep and 26 inches in width. The print area is 22in x 22in x 18in. These Print areas where not designed this size to actually print objects that large, but to be able to add extra components to the printer in the future.
All of the structural components are made of wood, specifically 3/4in MDF. The Z axis is controlled by 2 Nema 23 stepper motors, 4 ball screws, and 4 linear bearings. The XY axis is controlled with timing belts, at some point I do wish to switch over to ball screws for it as well.
Included are some pictures of my XY gantry and a 3d model of my Z axis. This printer is 99% operational, the only things left to do is to tune the feed rates and other aspects of the printer.