Ah. I'm so in love with these. I saw a photo of something sort of similar on pinterest but it was made with all wood, and it helped me come up with this design. Kind of the same way that Dan made the copper and wood shelf (see post here), we had planned to do more of a step-by-step DIY, but it ended up being a little more finicky than planned. So if you plan on making something like these, just make sure you have a bit of patience, and a level!
The length you cut the wooden dowel will depend on how deep you want to make your shelf! We did them 1 1/2 x 1 foot. You'll need to cut a piece of wood to go along the bottom of the back as extra support as well. These you can cut before hand, but the dowel I recommend using a hand saw, you'll want it measured out just right once you have the first base mounted on the wall.
Ah, so pretty, simple, and minimal. I'm in love.