About this 3D model
Simply print 2x Bottom and 2x Top and insert rods. Diameter of the holes is 28.1mm. You need rods with a diameter of 28mm. I used old curtain rods made of wood with 27,76 mm diameter and I bought some wood rods in the hardware store with 28 mm diameter. Preparation: 4 rods of 30 cm for the height 4 rods of desired length I first used 95 cm length, but siwtched to 120 cm length. Everything is plugged in, no glue required. Easily holds over 30 spools of filament. Printed with 3 walls/top/bottom and 15% gyroid infill in Prusament ASA. Maybe print just one part first and check if it fits your rods. Should work with other filaments, too.