I had always planned to use my Core One with legs and place a tabletop on it, turning it into a functional table. 

Because of this setup, top intake was no longer an option, so a side intake system became essential.

This design can be assembled using the stock screws that come with the Core One. As for the open gaps next to the vent, there are a few different ways to fill them. You can either print the gap-filler panel included with this design, cut and reuse the original panel that came with the Core One, or prepare your own 2mm-thick panel. In my build, I used a new 2mm acrylic panel.

Required other than printed parts:

• 4x M3x10mm screw
• 4x Insulating insert
• 4x M3nN nut
• 4x Nylon rivet

Parts to Print:

• 2x vent_cover.stl
• 2x vent_panel.stl

The same model is used for both the left and right sides, but if you want the visible surfaces to match, flipping the bottom surface of the model on each part.

Assembly: 

1. Run all four M3x10mm screws through the insulating inserts.

2. Pass the screws through the vent panel, place the vent cover on the back side, and secure it with nylon nuts. Make sure the vent can still open and close properly.
Repeat this process for both sets.

3. Secure the panel to the frame using two nylon rivets in the marked openings. Install the other side in the same way.

Note:

• The vent needs to be installed at the front side of the printer to efficiently direct cool air to the hotend fan. It should not be installed at the rear side.
• The slits on both sides together provide an opening area equivalent to the stock top vent.
• I recommend using PETG. Avoid printing with PLA.
• I’ve also added a version that uses an insulating insert you can print yourself.
• A mod for mounting a tabletop on the Core One.
  Prusa Core One Tabletop Spacer
  https://www.printables.com/model/1442781-prusa-core-one-tabletop-spacer