This is a system I've been working on for storing and using filament with my Printer stand. It uses Sch 40 PVC pipe, and printed arms to rack your spools. Easily switch colors in prints. Elements to come are filament guides, spool spacers and filament retainers. tested with Ultimachine and Makerbot spools (and small loose coils.)
a length of Schedule 40 1" PVC pipe and some Wood Screws.
Update: I fixed the .STL file, the holes are now printing correctly, and the model has been scaled to fit the PVC pipe correctly. If you downloaded the old version, please delete it and download the new file.
Print at least two of the arms. Medium quality with 3 shells and 15% infill (minimum quality settings) longer rods can use multiple support arms. I use three (one is to act as a "Kickstand" when adding and removing spools, so it's not screwed in, and is removable) and two arms can support about 6+ 1Kg spools. the higher the quality, the more robust your part will be.
Cut a length of Schedule 40 1" PVC pipe. push the arms onto the pipe and align, hold (or tape) the PVC and arms into position, and mark the bases and screw holes under the table top. remove the rod assembly, drill pilot holes, and then remove the arms from the rod, and, using wood screws, attatch the arms to the underside of the table.
push your PVC pipe through the rings on the arms. slide the arm ring off one end of the pipe, add your spools, and return the pipe to the ring.
It's a tight fit, but that's the way i wanted it. You can scale this thing. if you don't think it's sturdy enough, you can scale it to as thick as you want.