Box fans are my go-to cooling for hot summer days. The annoying part is to make these stand by the windows to provide optimal air flow from outside. I made these 3D printed removable window shelves to sit my box fans perfectly at the window without worrying about them falling off.

Step 1: Step 1: Measure

Every window track is different, so I need to measure the dimensions for each window. Measure within the nozzle and layer height of the printer to get a nice tight fit. I put them down in a drawing.

Step 2: Step 2: Add Shelf Top

Once the window track drawing is done, I added a shelf top, and extended this top to make more generous space. I use a curve to strengthen the extended top while saving material.

Step 3: Step 3: Transfer Drawing to CAD

Next, I use a 3D modeling software - for me, it's Autodesk Fusion 360, to transfer my drawing into a CAD drawing. I make sure my dimensions are correct.

Step 4: Step 4: Extrude

Next is simply extruding the profile. I make it quite thick, at 25mm (2in) so the platform is wide enough for a stable surface.

Step 5: Step 5: 3D Print

3D print is very easy for this shape, I have shown the orientation. No need for any support. Infill can be quite small, I used 10%.

Tip: I took a partially printed profile to make sure it fits correctly before printing them all.