I made all the uprights out of 3/4" plywood. The shelves themselves are laminated pre-made shelving pieces from Home Depot that are 11.5 inches deep. The sets are in two pieces: a long side measuring 4 feet in length and a shorter 3-foot side. The two pieces form an L-shape which fits into the center corner of the cubicle. The longer side has a center shelf and both the upper and lower shelves provide 12.5 inches of vertical clearance. The overall unit stands 26.5 inches high.
The vertical supports are not permanently attached to the shelves. Instead, the are held in place between cleats which are attached to the underside of the shelves.
On all the upright pieces I removed the rear bottom corners, and notched the bottom centers to allow for wiring (phone, computer, etc.). The larger notches in the front of the uprights are mostly decorative, but also allow more light into the shelving and make items on the shelves easier to reach. Finally, I stained the plywood to better match the pre-made shelves.
Below are some final photos of the finished shelves in place in the workspaces of my friends Jack and Jeff.
The image below is a link to a photo animation showing the shelves being assembled and disassembled.
