Parameters
Holes
3.5mm
7.00 mm for the bolt head
6.00 mm for the female screw
5.20 mm bottom hexagonal (female screw)
Fan size:
50.20 x 50.20 mm distance between holes mid point
hole size 4.20mm and 6.50 for the bolt head
Commutable button panel for extra buttons
Corner rounded 3.5mm Radius constant
This designed to
RepRapDiscount Full Graphic Smart Controller
https://reprap.org/wiki/RepRapDiscount_Full_Graphic_Smart_Controller
https://reprap.org/wiki/RAMPS_1.4
Arduino Mega
I will try to upload soon
Printing
No support needed
For the top try different settings, for nice honeycomb grid
The author hasn't provided the model origin yet.