Finally got my new E3D-v4 hot end installed and working.

Finally got my new E3D-v4 hot end installed and working.
I had to lose the wing nuts and reverse and shorten the bolts holding the extruder to the X-axis because they collided with the new cooling fan.
I also had to remove my custom ducted part cooling fan (having only recently printed a new improved version) because the nozzle fan and fan mount wouldn’t fit inside it.
I can understand how the new hot end needs its fins cooled but I’m now thinking about how I could combine nozzle cooling and part cooling into a single ducted design. I know I’m not the first person to attempt this interesting challenge but I don’t think I’ve yet seen a design that exactly fits all the criteria.
The nozzle shaft needs cooling all the time but the printed parts needs variable amounts of cooling depending on material, printing speed, layer printing time and Z height (high rates of part cooling at Z=0 will deflect off the bed and also cool the bed and the nozzle tip which is undesirable). Effectively, that either means a single fan which is on all the time but with a means of controlling the air flow, or a dual duct design with two separate fans, always on for the nozzle and variable speed for the printed part. Anyone else trying to tackle this?
It’s still early days but so far I’m impressed with the price and build quality of this nozzle and am looking forward to printing some more great parts soon.

Are you trying to do this on a Mendel90 ? I think separate fans is the way to go as controlling the airflow would vary the hotend cooling and introduce a variable into the calculated part cooling done by Slic3r. I am considering an E3D V4 for my M90 but want to mockup an install before buying.

Hi @Richard_Gain I have had the E3D nozzle running on a Rostock over the weekend, with a 40mm fan cooling both the fins and the part (not using the E3D mounted fan) - it does not seem to need as much cooling as the E3D fan assembly provides, so having a dual duct and Part fan could be a good way to go - I would really like some sort of shutter / shut-off / divert system (no that’s getting too complicated) but maybe a dual fan setup is the easiest way for now for these types of nozzles, especially at faster print speeds.

It’s another nice nozzle isn’t it, plenty of good options around now.

I’ve been enjoying the E3D nozzle on my Mendel 90. I wired the fan up to the fan port on +nophead 's x-carriage circuit board, and adjusted the firmware to have it always on. In a much earlier conversation, I pointed out a micro servo (a “feather” model used on small RC planes) could be used to actuate a flap. The circuit driving the flap could be adapted to be controllable via the pwm fan signal, so stanard g-code would control the flap, and the whole setup would be powered by the same source.

Perhaps we should have a dual duct, with two channels and two fans moved out of the way.

@William_Frick - yes, it’s now fitted to my Mendel90. I have @nop_head 's original design, not the newer kit version with larger capacity and redesigned extruder, so I’m not sure if things would be easier or more difficult now.
@Richard_Horne - yes, I watched your video and was inspired to sort mine out!
+Anthony White - I used to control my ducted fan manually. The spare port on my Sanguinololu is driving the LCD+ClickController.
+Sanjay Mortimer - glad to hear lots of ideas being considered. The nozzle is exactly the same size as the German one I was using before, so height is not a big issue for me. Yes, I noticed the duct was a notch too low but I was having problems fitting it and once I got it there (with a bit of a crack) I decided to leave it for now.
@nop_head - Agreed. For me, the dual duct, dual approach seems the most attractive at the moment. I’m OK whilst I stick to ABS but I think I’ll miss the cooling fan when I go back to PLA.

I’m going to try mounting a second fan (specifically a Centrifugal fan) somewhere on the chassis, and then running an air-hose from the fan down to the extruder. Hopefully this should mean a little less weight on the X carriage, and the hose should be about the same weight (if not less) than wires to run the fan. main thing is to avoid the hose getting twists in it.

From experience air has a lot more viscosity that I imagined. Blowing down any length of tubing requires a lot of power unless the tube is a large diameter,like 20mm…