I designed this so I had some where to put spools side by side instead of having them stacked on top of each other so I won't have to play Jenga every time I grad a spool.
Printing I recommend PETG but PLA works fine too, it'll just be a little more brittle.
To assemble screw in the first set as close the end of the table you can it will fit between the table legs if you have another table on top. Next measure 155mm from the end of the first set and place the end of the other set there and screw down.
The 155mm distance works best for all my spools which are mostly Hatchbox and Amazon Filament. The racks holds 6 spools each and still have some wiggle room but this will based on your spools