This is a build plate organizer designed to store 4 build plates approximately 250mm x 250mm in the top (smaller) drawers of an Alex It should comfortably hold sheets up to 280mm x 270mm in the pictured configuration. Larger plates could be accommodated by increasing the space used, though using taller drawers would probably be necessary.
With 280mm x 270mm or smaller build plates the plates fit within 8u.
I used https://www.printables.com/model/366128-ikea-alex-wide-gridfinity-baseplate for the baseplate for this project
This project prints as 8 parts. There is a left set and a right set. The base plates should be interchangeable between the left and right sets. They are attached together using 8mm M3 socket cap screws with M3 hex nuts. You can use nuts and bolts in all 16 holes for maximum strength, but in my experience it was reasonably sturdy with 12 holes populated.
Therefore you need at most:
16 x M3 8mm Socket Cap Screws
16 x M3 Hex Nut
Parts should be oriented for printing already. No supports needed. Print:
2x 5x1 Baseplates
2x 3x1 Baseplates
1x 5x1 Upper piece (LEFT)
1x 5x1 Upper piece (RIGHT)
1x 3x1 Upper piece (LEFT)
1x 3x1 Upper piece (RIGHT)
I printed them using the 0.2mm SPEED setting for the MK4/MK4S.
I had issues with the print sheet for the RIGHT set in the picture due to an issue with my build plate, yours should print much nicer (like the LEFT set)

You can customize the design, it is available in Openshape: https://cad.onshape.com/documents/eae3c58070f47681a753723f/w/1e177bac2219fe43e057e6cf/e/597ba093017ec814fd16cb50?renderMode=0&rightPanel=variableTablePanel&uiState=6777456c47ab0e734a29d2ef
The author marked this model as their own original creation.