Maker farm i3v rear-mounted cooling duct

thingiverse

After installing a servo, I realized my side-mounted cooling fan wouldn't function and didn't want to clutter the front of the hotend with more junk. That only left me with the back of the extruder as an option, which I've had in mind for some time but is a tight squeeze, at least with the relatively short (55mm) Hexagon hotend. This fan duct attaches to the back of the carriage using two M5x10mm bolts through the holes on either side of the bottom wheel mount. The internal shape that results from this setup appears convoluted, yet it seems to work okay. A 40mm fan can be mounted with M3x10mm screws. The design is parametric, which makes it possible to alter it for a different hotend or larger fan. The duct can be printed in one piece or split into two pieces that can be joined using a M3x10mm screw. If you need to experiment with the vent size or shape, printing just the vent and attaching it to an existing frame is faster than redesigning the entire thing. Update 2016-02-06: I've added an option to skew the vent tip inward a bit to direct air closer to the center, though I haven't tested this yet. Update 2016-02-13: I've updated the design to allow loading X carriage and hotend models to display their relative positions and a rough idea of airflow. The Hexagon duct has also been redone (testing indicates significant improvement) and an E3Dv6 version was added. Update 2016-03-05: Version 3 of the Hexagon fan features better wheel clearance and possibly up to 20% more airflow, although I haven't uploaded the SCAD file for that because I need to fine-tune it for use with an E3D. Update 2016-03-13: I've uploaded v3 of the SCAD file and also made the E3Dv6 version available. At this point, I'm considering this done. Update 2016-10-16: Pegasus + E3Dv6 versions are now available. Print Settings: Printer Brand: Printer: Makerfarm i3v 8 Rafts: Supports: Resolution: Infill: 30% Notes: If you're printing in two parts, the vent will definitely benefit from a brim or even a raft. I printed this in natural PETG.