I really like the Gridfinity Case by Aiko since but the the model is extremely resource hungy - without any sacrifice in functionality or robustness i shaved down everything to yield about 33 % savings and added a list of other cool features

Key Features

• 5x4x6U, 9U and 12UGridfinity
• roughly 220x190x50 mm for 6U (~71 mm for 9U; 92 mm for 12U) 
• top and bottom Grid (no parts spilling out)
• resource friendly, yet rugged
• stands upright in 5 orientations
• 12 mm label slot in the front
• dozens of color combinations and logos for you to pick

for your convinience i've included various logos if you want to store your printer accessories in the box - if you miss a logo, just drop me a line

BOM

• 6x M3x30 screws
• 2x M3x16 or 2x M3x18 screws
• PETG or ABS recommended, PLA is OK aswell
• TPU (optional)

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Printing

• Lid and Base: flat on build plate, 3 walls 15 to 20 % infill
• Latches: upright 3 walls, concentric top/bottom
• Handle: flat on build plate; 3 walls, 30 % infill; concentric top/bottom
• Seal: Flexible Filament; flat on build plate; 3 walls concentric top/bottom
   

Colored Logo

• the lid with all the logos is a separte multipart file, use your faviourite slicer and multi color system to print it - in Orca Slicer, Bambu Studio or Prusa Slicer just remove all the logos except the one you want to keep and turn it into a modifier with the desired color

Assembly

• longer screws in the hinges or latches (from the outside)
• shorter for the handle (from the inside)

Changelog

2024-05-18 v31:

• added a 9U version

2024-05-18 v33:

• added a 12U version
• slight geometry change to the label slot to make it easier to print (thx to Markurian for the input)
• parts are fully compatible
   

Changes from Original models

Akio

• thiner lid and bottom
• no magnets
• moved the handle to the center
• fixed “unprintable” fillets on the underside
• added 0,2 mm tolerance for closing the lid
• changed the lid tilt angle and inner width slightly
• reworked the inner lid geometry
• added a slot for a label

Pred

• original source
• inner geometry for lid used as base for revised geometry

Whity

• outside geometry as base
• chamfers and fillets on top/bottom
• latch geometry with chamfers

PeterDesigns

• parametric handle, shortened
• rib for upright position
• overall crosscheck and trial/error for dimensions/prototyping

material, time  and size savings

• before:  ~ 12 h; ~ 420 g; > 65 mm height
• after: ~ 8,5 h; ~ 325 g; < 50 mm height