I used this design to separate the hotend and part/nozzle cooling to quickly test different part cooling designs. Currently, the hotend is cooled by a 30mm fan whereas the part/nozzle is cooled by a 40mm fan.The airflow which cools the nozzle/part is distributed around the nozzle to avoid wind-shadowing. With the current design I get some pretty good bridging results (>35mm @ 195° w. PLA Geeetech Black), at least compared to the stock cooler.
With the new design bridging over the whole printarea is possible. Since the airflow is better I had to increase the printing temperature for adhering layers during bridging. Maybe I will add a design with a 30mm partcooler which I think might be sufficient for the par cooling
To mount this a bit of leveling/adjustment is necessary since the design defines the horizontal position of the nozzle and, therefore, the height of the print bed.
I printed everything with PLA. After now more than 10h with the new cooler I had no issues with melting or whatsoever.
I uploaded the mounting part (Fusion360) so you can design your own part cooling.
4 x M3 Nut
2 x M3x10mm screw
2 x M3x25mm screw
1x 40mm fan
First Airflow Design
The issue with the first uploaded design is the airflow on the bottom side of the fan. As you can see from the cross section the fan blows the air directly against the wall which leads to turbulences and decreases the possible output. Though I had no real issue with this design it did not satisfied me.
The new design should have a better airflow.
For the new part cooler design I changed the mounting angle of the fan so that it is perpendicular to airflow. Everything that was in the way of the (expected) airflow is removed.