This is easy-to-print and efficient remix from BMG Duty 1st gen for  Ender 3 / CR-10 printers.
This remix features the ability to use with a stock 34mm stepper motor and the ability to hotswap e3dv6 and volcano extruders.
Due to the location of the mounting bolts, the original radiator fan mount is not suitable, so use one of the loaded ones.
You can use the original fan duct and the ones loaded here.
The original ducts have the ability to adjust the position relative to the nozzle.
The loaded ones are distinguished by the use of the m4 bolt for mounting the fan and only two positions - the upper one for the e3dv6 and the lower one for the volcano. This saves you from having to adjust the position of the ducts.
Fasteners used:
4 or 8 x nut M3 (depends on the fan duct used);
2 x nut M4 (depends on the fan duct used);
3 x 10 mm bolt M3 (for mounting main_mount);
2 x 17 mm bolt M3 (for mounting model_fan_ducts);
2 x 27 mm bolt M3 (for mounting radiator_fan_duct);
3 x 35 mm bolt M3 (for mounting BMG + stepper);
2…