Step 3: Drill the Holes in Your Shelves
Now, in order to prevent the shelves from sliding up and down the cable I used a metal stop (pictured, but more on that later). I didn't want these stops to be visible when looking at the piece, so I used a spade bit to drill a slightly larger hole on the bottom side of each shelf. This way the stop would sit up inside the wood and be concealed.
Of course you want to be careful that you don't drill too far and you want both sides to be drilled evenly. To do this, simply place a piece of tape on your spade bit and when the tape nears the top of the wood, you know to stop.
As long as you can still see your drill bit below your tape you keep going.
But when the tape meets the wood, STOP!
And here's what it should look like when you're finished.