The top locates a 40mm Fan.
The bottom is just open, so air and wires are free to exit.
The primary problem I was trying to solve was the RAMPS fan causing a draft across the printing bed. This does the job nicely and it protects against knocks/dust etc.
Two parts, the part which screws down with the RAMPS1.4 board to the Prusa i3. The otherpart is the simple case which hooks onto the 1st part.
*UPDATE MK2*
After printing new plastic parts from:
https://github.com/josefprusa/Prusa3
The clearance between my x motor and the Arduino was not sufficient so the motor would crunch into the case with every Z axis move.
So I printed a new ArduinoMountPlate (ArduinoMountMK2.stl), this ensures that there is enough clearance between the x motor and the case. The original ArduinoCase is compatible.
I have also done away with the little legs for attaching the two parts together, these were too thin and broke, I now use the power of elastic bands! works great.
UPDATED the ArduinoCaseMK2.
I got rid of its weak little legs too.
See:
http://www.thingiverse.com/thing:167976
