This is my concept of a Filament storage shelf.
I used 12 mm steel rods for the connection between the brackets, but you can also use wood or aluminium pipes. Maybe it will bend a bit in the middle in this case i also created an bracket to support the middle.
You shoud print this in ABS oder PETG. I didn´t tryed it in PLA
I printed it with a 0.4 nozzle with 4 perimeters for stability. Do not use less then 25% infill (triangular or honeycomb).I used 25% and it works fine
You maybe need a brim. I desiged the parts to fit well on a 20 x 20 cm Printbed. The size of the holes is 12.2 mm diameter you should need about 100 gramms each part. I also added some simple screw coverplates :-) Have fun with it and share your pictures with us!