Dave's Upgraded E3Dv6 Fan Duct by orgemd

Last crawled date: 2 years, 12 months ago

I have been moving towards using the E3Dv6 hotend for my printer. Since I print ABS, however, I have concerns about the active cooling this hotend requires. I therefore wanted a way to duct both the intake and outlet of that cooling - minimizing the possibility of drafts impacting the printing. The stock E3Dv6 fan duct does not allow for that. I found thing 375419 by rmoncello, and thought it was a brilliant, beautiful solution. When I printed it, however, I had some issues. In particular:
the central hole was slightly too small for the heatsink so that the parts would not completely close
even if the central hole was correct, a lot of air was going to escape out the seams
the fan hole was not constrained to the cooling fins so that a lot of air could escape
the model did not seem to account for the slightly different size of the bottom fin
although the part had nice looking curves, those curves made it harder to get a good clean print
screw holes were too small and shallow - requiring hand drilling - and had no way to link the two halves together
For this version, I made the following adjustments:
I adjusted the central hole size to better fit my heatsink and made an allowance for the larger bottom fin - with a choice to make the top of the duct flush with the top fin of the heatsink, or the bottom of the duct flush with the bottom fin of the heatsink.
I adjusted the fan hole to limit flow through the fins - again with a choice of if the duct sits aligned to the top or bottom.
I simplified the shape to improve printability.
I added overlapping ridges to better seal the seams between the two parts.
I adjusted the screw hole diameter and depth to better allow tapping of those holes, and made it possible to link the parts with screws through one part and into the other.
This version is available as an OpenSCAD script so that modifications can be made as needed. I have not exposed a lot of parameters. The only easy changes in the SCAD are the size of the screw holes and whether the alignment should be to the top or the bottom. More modifications can be made, however, with a bit of OpenSCAD knowledge.
Update - 2014-09-09 - Having assembled the full hotend, the version that aligns with the bottom fin works great, but I would not recommend the version that aligns with the top fin. The printed part would have to be right on top of the heater block - if it would even fit. I might look at it a bit to see if maybe I can do something to open up a bit of space there in the future.
Update - 2014-10-05 - I have uploaded a new Update2 version. This is to fix the issue when trying to align to the top of the top fin on the heat sink. I would not recommend doing this. I would recommend aligning to the bottom fin. Otherwise, the duct is close to the heater block. If, however, you want to align to the top, this carves a space for the heater block and also allows a parametric stretch of one or both parts of the duct to make room. In the pictures, I used a stretch of 0 on one half, and 5mm on the other half. I would still use 0 stretch on ducts aligned to the bottom. The scad now draws both halves at once.