High performance cooling assembly

thingiverse

This is a helix fan duct designed to work with a 40mm fan that has a blower, optimized to redirect and straighten airflow with maximum efficiency. It's specifically designed to attach to the Wanhao i3 v2.1 printing head using two 20mm M4 screws with conical cross heads, while holding everything together with stock M3 screws. All threads in the holes print well enough at a layer of 0.2mm and match the stock M3 screws perfectly. The bottom surface of this duct is designed to be at least 2mm away from the print bed at its minimum Z position. I've also included suitable supports in the model. This design is an improvement over my previous one, with the addition of a helix duct inspired by DaveGun's Vortex Fan Shroud. Like my previous design, this one resulted from several CFD simulations. The assembly consists of three parts: a helix duct with a 40x15mm rectangular exit, a positioning frame, and a blower duct. I designed it this way to make switching blowers possible without having to reprint the whole thing and also to allow using this efficient helix duct on any printer or in any other application that requires airflow. I've included models of 2mm thick dampening inserts made from flexible material to reduce noise and vibrations from the fan. Compared with my previous design, this assembly provides even more flow (up to 4.3 CFM) and has less adverse effect on the nozzle temperature level. It's designed to provide cooling for two zones: main airflow goes around the nozzle and a limited amount goes directly beneath the nozzle through a separate channel, allowing high flow rates in general while providing cooling of just extruded material without causing too much temperature drop of the nozzle. I've also included a blower version without a small channel to further limit nozzle temperature drop if you don't need to print severe overhangs or small parts. Four 1.5mm holes provide cooling airflow to prolong blower life under high temperatures (I printed it from PLA and used it to print at nozzle temperatures as high as 245-250C, and it survived the print without noticeable damage). Printer Settings Printer Brand: Wanhao Printer: Wanhao Duplicator i3 V2 Rafts: Doesn't Matter Supports: Yes Resolution: 0.2 mm Infill: 100% Notes: 0.4mm extrusion width; max. printing speed 25 mm/s; Used custom supports, no other supports required; Printed from PLA 235C nozzle, 70C bed and 0% fan at layer 1; 235C nozzle, 60C bed and 100% fan for the rest of the print. Dampening inserts were printed from Ninjaflex at the same settings except for 150% extrusion rate and 20 mm/s max speed.