What to do with empty spools? I asked myself, than I saw some similar shelves, but none of them was "that" type. So I did this. Hope it will be useful.
You need four main parts for each level. I glued it to the spool with cyanoacrylate. There are bearings between spools. They are designed to use 6mm plastic BB gun balls, so it is very easy to get them. Or you can use any other 6mm balls.
I recommend to put a pipe through whole organizer and fix it on the table. Locks are not much reliable and it can happen that you will pick dozens of your things from the ground. Just be carefull.