Yet, yet another fan mount to be used if you replace your stock Robo3D R1 hot end with an E3D v.5/6
We just received a new R1 and the M4 extruder mounting screw doesn't fit the mounting hole in PD5DJ's fan mount (thing 480350). This was derived from that thing but I have opened up the counterbore to accommodate the screw that Robo3D is currently using.
I also chamfered the approach to the fan to improve intake air flow.
As PD5DJ says, an easy, clean build.
I just did this in PLA - 2 shells, 60% infill, 0.25mm layer height.
You have to mount the bracket first in the same location as the original factory bracket. Then mount the factor fan to the bracket.
Then install your new hot end.