This is a small-profile (left-to-right) fan mount system for the E3D V6 hot end. It uses a 30mm fan to cool the heat break (basically, uses the fan that comes with the E3D V6 hot end). And, it uses a 40mm fan for the filament cooler.
This fan mount system should work on any machine that utilizes the E3D V6 hot end. I designed this to allow my modified MakerGear M2 to be able to use a mirrored BondTech QR extruder and an E3D V6 hot end without losing any X or Y travel (Both of these upgrades are AMAZING on an M2 - I now have absolutely no trouble extruding). NOTE: If you upgrade your M2 to the BondTech extruder and an E3D V6 hot end, you will need to also update your firmware with new settings, cut the aluminum mounting plate on the X-axis to get clearance for the E3D V6 extruder, rewire the extruder stepper connector, enlarge the extruder stepper connector cutout in the black plastic wire junction box on the side of the X-axis extruder, and extend the X-axis homing bump-stop by about 10.3mm. This is a lot of work, but it really does greatly improve the performance and capability of the M2 (IMO).
The fan mount system is simple to print and assemble - just two printed parts. Please note that there are two different heat break mount designs included; one is for the original E3D V6 (they have a heat break diameter of 22.3mm) and the other is for the Chinese version (I hear they have a 25mm diameter). I am using the original one. I have not printed nor tried the Chinese variant - I have included it here in case anyone might need it and would like to try it (I would love to hear feedback from anyone who tries this to let me know if it works or doesn't work).
For a complete assembly, you will need to print one of the two heat break mount designs (original or Chinese) and the filament blower design.
I have also included an AutoDesk 123D design file to make it easy for anyone to modify fan mounting hole patterns in case either of your fans has slightly different spacing.
For the fans: I used the 30mm fan and screws that came with the E3D V6 (25mm hole spacing). For the 40mm fan, I used the one on the M2 that was originally used to cool the extruder. I mounted the 40mm fan with #6 x 5/8" sheet metal screws (32.5mm hole spacing). If the hole spacing of either of your fans is different, use the attached 123D file to change it to fit.
I recommend using (2) M3 x 16mm (or #6 x 5/8") or longer machine bolts, washers, and nuts to assemble the heat break mount to the filament blower. The height is adjustable by a few mm.
To set the height, first assemble the two fans to their respective pieces (be sure to note proper fan direction and orientation for your wiring). Then loosely assemble the two fan assemblies together using the M3 hardware. Snap the assembly onto the E3D V6 heat break and zero your Z-axis. Adjust the height of the filament blower so that it rides about 1 to 2mm above the bed and tighten the screws.
eSUN ePC recommended - UL94V2 rated
You should use a heat-resistant plastic for the heat break mount, such as ePC, ABS, PETG. I do not recommend PLA as it is not heat-resistant enough. eSUN ePC is great to use for this application as it is UL94V2 rated (i.e. self-extinguishes flame in case of fire).
I recommend printing with 2 shell layers for strength and with the orientations set in the STL files. The files are designed to need minimal-to-no support. However, the large fan hole on the heat break mount may need a little support towards the top, depending on your print settings.