I originally documented this project on July 12, 2017. The first photo in the gallery is current; the others are from the original post. This shelf elicits positive comments from nearly everyone who sees it. It's one of my favorite projects.
My wife and I wanted a set of shelves to mostly fill the back wall of our study, but we wanted something different and unique; we didn't want a heavy looking wall of bookcases. My wife had two more requirements: the shelf had to be made of wood (unpainted), and it had to float on the wall instead of resting on the floor.
As usual, we went to Pinterest for inspiration and found a few things we liked, but we didn't find exactly what we were after. Eventually, she came to me with a rough conceptual sketch, and I refined the design in SketchUp. These photos show the finished product.
It's a very large unit, 78" tall and 99" wide, with chunky (1 3/4" thick) shelves. Given that, I was very concerned with its weight. I had to be able to build it, and we had to be able to get it on the wall and have it stay there. My rough estimates showed that it would weigh over 200 pounds if I made it from solid wood. That was way too heavy.
I solved the weight problem by building each shelf and side as a torsion box. Each shelf/side is a skeleton of 3/4" plywood spines and ribs covered with thin (0.2" thick) plywood skins. The back panel is constructed similarly. The entire unit weighs about 100 pounds. The longest shelf (87") weighs 15 pounds, and the shortest (54") weighs 11 pounds. It hangs on three French cleats hidden in the center panel.
The skins are made of 5mm RevolutionPly underlayment I found at Lowes. As far as I can tell, it's a 3-ply product with a reconstituted veneer face on one side and primer on the other. The veneer side looks like quarter sawn wood. It accepted Danish Oil (Watco Natural) just fine, and it's also very affordable ($14/sheet). I'm happy with it for this application.
For more details, see my series of blog posts
(at LumberJocks, to be migrated to Craftisian later) for this project. SketchUp models
are also available on the 3D Warehouse. Thanks for looking.