I have been searching for the perfect small parts organizer box, and when I found bilboDD's Gridbox, I was very excited. The 5x5 version is a useful size and just fits in my Bambu X1 Carbon.
Unfortunately, I discovered that with 6U high Gridfinity bins, small parts can easily fit between the top of the bin and the lid and will make a mess if you aren't careful when handling the box.
I took this as an opportunity to learn how to modify STEP files, and used Onshape to make the lip of the window lid a couple of millimeters deeper to fit tightly against a 6U bin.
Since that made a deeper indentation in the top of the box, I added an extrusion on the bottom that lets you stack boxes so they don't slide around. It does mean you need to use supports to print it; I recommend setting the threshold angle for supports in your slicer to 10 degrees so it will only add supports for the bottom lip and not the hinges.
For divided bins, they should not have a lip on the top and the bin dividers should go all the way to the top of the bin. I've included a set of pre-configured Gridfinity bins that are customized for this case in the “Bins - NxN” directories.
