UPDATE 12/04/20. This case also works with SKR 1.4.
UPDATE 12/12/19. I uploaded .stl files of Ender 3 and Ender 3 PRO case with 4020 fan. Look for the '4020fan' in the file names. To avoid confusion, you will need to print:
Ender 3 with 4010 fan (stock version of fan):
Ender3_case.stl
leg.stl, 3x
Ender3_cover_left_2.5mm.stl AND Ender3_cover_right_2.5mm.stlOR
Ender3_cover_left_3mm.stl AND Ender3_cover_right_3mm.stl
Ender 3 with 4020 fan (20mm thick fan):
Ender3_case_4020fan.stl
leg.stl, 3x
Ender3_4020fan_cover_left_2.5mm.stl AND Ender3_4020fan_cover_right_2.5mm.stlOR
Ender3_4020fan_cover_left_3mm.stl AND Ender3_4020fan_cover_right_3mm.stl
Ender 3 PRO with 4010 fan (stock version of fan):
Ender3PRO_case.stl
leg.stl, 3x
Ender3PRO_cover_left_2.5mm.stl AND Ender3PRO_cover_right_2.5mm.stlOR
Ender3PRO_cover_left_3mm.stl AND Ender3PRO_cover_right_3mm.stl
Ender 3 PRO with 4020 fan (20mm thick fan):
Ender3PRO_case_4020fan.stl
leg.stl, 3x
Ender3PRO_4020fan_cover_left_2.5mm.stl AND Ender3PRO_4020fan_cover_right_2.5mm.stlOR…

cable tunnel for the Ender 3 Pro boxes fixed!
Added a MKS gen L version (only removed the SD card, the rest fits)
single fan covers added!
Photos are of my old design. new fan grill added!
Ender 3 Pro box added!
I created this box because I wanted to have the SD and USB on the front side.
I have 3 Lm2596 buck converters in here (hotend, part cooler, board cooler)
I kept the fans on top because when it prints the bed is always over it. I have placed 2
and they are right on top of the drivers, MOSFETs, and processor for best cooling.
after I printed mine I noticed the cable of the LCD didn't fit and the SD card was hard to remove. I have fixed this but I haven't printed it yet for photos. also i sinked in the screws on top dieper. M3 treats modeled in