Not sure if anyone else has already made this, I didn’t find it online. Does anyone see anything I missed about why this wouldn’t be an improvement?
I use a pair of E3D-V6 hotend and I made a couple of fan supports, one for each hotend, similar to your design. I wired the two fans in parallel as I was no longer using the top fan. They work fine and are a slight improvement on the twin duct design I used before. (thingiverse.com/thing:750821)
Looks great! I might try it.
The PEEK (brownish) insulator needs some cooling. Maybe that is the reason the fan is originally placed higher. That is the only thing I can think of.
[quote=“Sketch”]The PEEK (brownish) insulator needs some cooling. Maybe that is the reason the fan is originally placed higher. That is the only thing I can think of.[/quote]That is exactly why it was positioned there. If you adopt this configuration, you probably shouldn’t try higher temperature filaments.
I modified this to center the fan more when it’s just one extruder. It still blows on the lower edge of the PEEK insulator as well, while the bigger fan above seems to cover the rest.
I’m already seeing an improvement in my reference print, the Marvin keychain.
At left is 100 micron layer height, at right is 50. The feet are a bit garbled on the left one because I’m still feeling my way with this DC Fix velour printbed liner. On the right I cheated and just added a raft. But look at those loops at the top! I never got those with the stock cooling. Testing continues (does it ever really end?)…
Where can I get that fan mount, would like to try it.
Try this, it’s stored on my own server. I have mercifully removed the HProps logo. 
K8400 Fan Extension
Hi! Could I have a link to download the straight one? I’ve have a dual extruder. Thank you.
Why yes, yes you can!
Straight Fan Extension for Dual Extruders
I just raised the fan mounting a few mm so that it will still cool the lower edge of the PTFE thingy. Works great on PLA, you might have to run the fans at less than maximum for ABS or any hotter filament.
Thank you. I’ve ordered 2 new 2.5cm fans. I plan to use 3 fans. One for cooling the brown plastic part, the two other for cooling the print just in front of the dual printheads.
Hello!
This fan extension is great and so far the quality of my small prints has improved SIGNIFICANTLY.
But does anyone have trouble getting the printer to heat up to temperature? It wont even hit the 210 degrees C needed for PLA. I have to physically hold the fan, and stop its rotation, to get the print head to heat past 190 degrees C.
When I let go of the fan after the print starts, the print acts normally (good flow and all), even though the temp display claims it has dropped to 185 degrees C.
I guess I might just be looking for a way to shut this fan off during heat up.
Thank you,
Kelsey
You can lower the fan speed to avoid this, in your slicer.
Temperature drops aren’t very good for jamming…
Dylan
I’ve downloaded this bracket (dual extruder setup) and found that the fan can only go to around 80% speed max for the nozzle to almost max out at 185C printing PLA. Print quality has gone up however for small pieces such as Marvin, but found he needs to be printed so he is facing side on (better air flow around his front and back for the overhangs).
I’m currently investigating using flexible tubes and a centrifugal fan to blow air down the tubes, pointing at the print job and not right at the heater blocks. The fan might then go back to purely cooling the PEEKs and the air lines just cooling the extruded plastic. It should be less bulky just having little tubes next to the print head rather than yet more axial fans on brackets blowing air down 3d printed funnels (which is what everyone else is trying). If it works well, I’ll take photos and report back!
In this configuration the fan is cooling your temperature sensor quite better than before. For me it is an indication that the thermal coupling between heat block and temperature sensor is poor, providing a chance to damage your nozzle (several issues in this forum).
However, in this configuration the real temperature at the nozzle is increasing, providing a print result equivalent to a higher temperature setting.
Please check the mechanical strength of your fitting for the temperature sensor. You should also think about thermal paste (non-conductive) to improve thermal conductivity between brass block and temperature sensor.
I am about to try to remove my blower fan, the E3Dv6 doesn’t need all that air going to the print itself or the heater block, but rather the heat break needs constant cooling. I have been told that making the fan “always on” was a solution so I don’t need the board controlling the fan. That means that I can set a temperature and not worry about the parts cooling too much.