When this setup runs, it pulls 3D printing fumes out of the workshop and sends them outside, which opens the door to printing ABS. The obstacle was clearance: where the ducting had to pass, only around 60 to 70mm of room existed, nowhere near enough for a standard 150mm duct.
Yeah Nah DIY worked around that by climbing into the attic crawlspace and scanning the timber framing with a handheld 3D scanner alongside a laptop, then modeling the part in Autodesk Fusion 360. A Bambu Lab H2D printed it using dual extrusion. What came off the machine is a wide rectangular-to-round transition: it starts at a round intake port, flattens into a curved run, and ends at a rectangular louvered grille.
Several details stand out. The duct is a two-piece white assembly held together with recessed metal screws, and the flange carries four screw holes for the mating segment. ASA was the material, suited to heat and UV outdoors. Down in the attic, an inline fan plus flexible ducting sit among the roof trusses, and the finished duct passes right over a wooden framing member inside a tight cavity, pushing air down through the ceiling.
One thing is unresolved. The printed piece was produced in PLA with dedicated support material that was detached by hand, yet the post describes ASA. Those two do not line up, and it remains unclear which material the final part really is. It is also unanswered how fumes were extracted while the ASA duct itself was being printed.
Project by Yeah Nah DIY. Watch it on their YouTube channel: