I suspect if the air can be directed very close to the nozzle tip it isn't necessary to provide a 360 degree cooling.
My current plans for the next iteration:
270 degrees cooling, so the nozzle tip can be seen again during printing
remove the 'fingers' and prohibit the air from blowing directly at the nozzle so the air stays cooler
use a 40mm blower instead of 50mm to reduce footprint and weight
maybe use a 40mm blower for the e3d heatsink as well? The fan duct uses a lot of space currently
Any idea where i can get a high quality 40mm 24V blower fan?
The 50mm one i'm currently using has pretty bad vibrations 😞
Maybe the old style silicon sock would be better suited as it shielded the nozzle better.
I suspect the radiated heat from the nozzle is a problem both for the print and the fan duct.
Where the screw that tightens the heater cartridge radiates heat, the fan duct fails first. It burns a hole in the PLA the size of the screw head.