This print has extremely tight tolerances compared to what I typically like. I did not account for any give in the threads and I used 6 M4x20 out of this kit: https://amzn.to/3zeasy6 .

I entered this into the Beauty of Mathematics because my print file:
- uses no infill for the shelves, but is holding at least 5lbs of weight in the photo

- has extended threading in the rods to thicken the wall strength without adding to the 5% of infill already there

- uses a hexagonal pattern at 10mm spacing to close the bridging distance and to strengthen the walls

- has zero tolerance at 0.28mm

- only uses 160ish grams of filament, compared to 320g of the first iteration

- when printed in a set of four, it makes a circle for pi