So, I am embarking on a design project and had some things I want to clear up. I had some questions about the cooling fan (not the heat sink fan, the extrusion cooling fan, starboard side, 24v). Just trying to wrap my head around it. I see so many different fan shroud designs. Some seem to aim right at the nozzle tip best they can, others seem to be aimed down at where the part would be. Just exactly what is it supposed to be cooling? Are we wanting it to cool the filament as its being extruded out of the nozzle, or is it supposed to be cooling the part already printed?
I print primarily in ABS so I very rarely use the cooling fan. I see lots of references to it with PLA so I presume its pretty critical for that material.
Anyone care to share the logic surrounding this fan appendage?