Why did I design this?

The stock cooling of the BIBO 3D printer is rather poor, so I decided to switch to 5015 blowers. There are already a few blower fan ducts on Thingiverse for the BIBO but many of them restrict the build volume. Because the build volume of the BIBO isn't that large this was no option for me. I experimented alot with different fan duct designs. I tried many different fan duct designs including curved and semi circular designs. At the end I experienced, that every edge or curvature just leads to less air output and less cooling. So I ended with this rather simple open design. I took two blowers because so I can run them with slower speed than a single blower and two blowers at lower speed are making less noise than a single blower at higher speed. I placed the blowers that they do not collide with the front frame.

Why is the left blower mounted that way?

It might seem awkward that the left blower is mounted with its back facing to the door, this is because unfortunately I just don't found any mirrored blowers to buy. If somebody knows where to buy one please let me know. Mounting the left blower on the back of the extruders was also no option because there wouldn't be enough space for a 5015 blower without colliding with the bearing bush of the Z axis. Fortunately it hardly matters that the left blower ist mounted that way. There's enough space between the blower and the extruder fan to let enough air through.