Modeled as an experimental design, to see if there's any way a decent shoe rack which can be made in FDM without wasting a ton of plastic. I pulled some inspiration from existing interlocking storage designs, but they are designed to be small and don't scale up to a size that can accommodate shoes very well.
So here is this. So far V1 is worse than I had hoped, unfortunately, but please feel free to use this idea as inspiration for something better. I am still working on it, maybe V2 will work better. This design is a WIP.
The faces themselves feel reasonable on their own even when printed in PLA, there are enough layers to give it some strength, but few enough that it remains a bit ductile and thus can bend a fair amount without stretching anything. Printing with more perimeters and higher infill might help with that somewhat.
However, this is a double-edged sword: At least in PLA, one hexagon on its own is incredibly weak and flimsy. At first I was ready to blame the clips, but the faces are so thin that even though the clips hold their edges quite rigidly, the faces actually have too much flexibility. This is a consequence of the design prioritizing material efficiency. Another downside to this design is you need at least 3 separate hexagons in order for it to have any chance of holding your shoes, and you probably need to double up outer faces, which means you're printing even longer...
The clips, at least, print ultra fast. Each hexagon needs 18 clips, and that takes 24 minutes for my MK2.5.