Similar to my previous upload, this cover is meant to keep as much dust out of your printer. Definitely not needed when using your i3 Mega as a 3D printer. When you convert it to a CNC machine, this might be a wise part to print and install.
You can mount this using four M4 bolts. I tapped the holes before mounting this, but I honestly think that's not even necessary. You can probably get away by letting the bolts tap the metal themselves.
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Printer Brand: Prusa
Printer: I3 MK3S
Rafts: No
Supports: Yes
Resolution: 0.2mm
Infill: 100%
Filament: ColorFabb PLA/PHA Ultra Marine Blue
Notes:
I used support material only for the top of the vent (in printing orientation).
The author marked this model as their own original creation.