Prusa MK4 under the bed trays

31/01/25 – Per request, I have added an STL file of the two trays with a depth of 20mm as opposed to the 30mm of the original model. This involved shifting the mounting holes by 4mm and is currently untested, but looks like it should work.

Similar to a set of trays I used with my previous printer, this set of models adds two trays under the heat bed for the storage of tools or other items.

The coding for these was done entirely from scratch in OpenSCAD but the design was heavily influenced by the following (if that means I should list it as a remix, let me know and I'll make the appropriate changes):

• https://www.printables.com/model/130808-prusa-mk3mk3smk3s-under-the-bed-storage-box
• https://www.printables.com/model/410322-easily-removable-lids-for-prusa-i3-mk3-mk3s-mk3s-u
• https://www.printables.com/model/522308-precision-fit-multicolor-mesh-side-boxes-for-mk3s-
• https://www.printables.com/model/522319-hex-twist-lock-for-prusa-mk3-mk4-extrusions

The trays are independent – you can install only one of them if you wish. If you do want to install the right side tray, you will need to first remove the cable clips which hold the ribbon and grounding cable for the MK4's controller/display. New clips, which can be glued with super-glue or epoxy to the bottom of the right tray are provided as a replacement.

I have also included a modified version of the Hex Twist Lock file from #522308 because their model caused my slicer to complain about overlapping support regions; however, the size of each element is the same. If you change the thickness of the walls, you may need to recreate a new set from #522319.

If you wish to make the trays deeper (and I may, if I decide to reprint them), make sure to adjust holeHeight by the same amount as height, as the tray's top edge must be no higher than the bar it is attached to or else the cover interferes with the heat bed's travel along the Y axis. The clips could also probably have clipDepth shrunk a little (I just made them as “tall” as the clips they were replacing), which would allow for more depth in the right tray as well, depending upon the feet you have attached to your printer.

May also work with the MK3 models, but this is untested.