This improved cooling system for the Hexagon (NOTE: NOT Hexagon AO) hot end on the MakerFarm Prusa i3 and i3v mounts the fan behind the hot end to keep it out of sight and out of the way. It also directs the cooling airflow away from the part being printed and away from the heated bed to help prevent warping.

This cooling system uses a 25mm fan mounted in the extruder deck behind the hot end to pull air up and vent it out the top, away from the print. A shroud around the hot end pulls air in through the front, across the cooling fins and into the fan intake. The (slightly) warmer air exits behind the extruder.

The small fan only moves a small amount of air (3CFM) but this air is directed exactly where it's needed, to effectively cool the hot end, and not the print or bed.

As an additional benefit, the hot end is fully visible from the front, so it's easy to monitor its temperature and detect leaks or other problems.

You will need a 25x10mm fan that can generate around 3CFM of airflow. I used a 12V Sunon Maglev fan available here:

http://www.digikey.com/product-detail/en/MC25101V2-000U-A99/259-1570-ND/2757808

It's quiet and generates plenty of airflow to keep the Hexagon hot end cool.

This new X axis shelf is compatible with the wood parts from the original i3v kit, and it's also compatible with my Z probe servo mount:

http://www.thingiverse.com/thing:335632

The shelf is also compatible with the i3, though the shelf brackets are different.

If you have any trouble with the hot end melting the shroud, you can make an insulator with fiberglass strips and Kapton tape. See the photos.