I really liked the leg design and modularity of Rup_Made's Rack for Gridfinity box 4x4, so I just had to copy them for a rack for mystoopidstuff's excellent Box For Stuff at https://makerworld.com/en/models/159840. This is for the 20-bin version.

Unfortunately, I had to split this in half to accommodate my 256x256x256 print volume. To start with, you need to print all four plates and piece them together. Additional layers, just print plates 1 and 2. Use an M3x10 SHCS at each leg to hold it all together.

I've designed this to be as light as possible on the filament but strong enough to hold several stacked bins.

The pieces snap together perfectly using my P1S with PLA basic, so YMMV with other filament. Regardless, I put a drop of CA glue at the seam of each dovetail and at the two midpoints between them for that extra bit of security.