This extruder fan pushes cooling air as close as I can get to the print nozzle without hitting the build plate. It is fully adjustable in all directions so you can make sure it points exactly where you need it.
This fan is mounted on the older extruder head where the mounting bracket is for additional extruders, so obviously if you have an extruder here you are out of luck :)
The model should print without supports and will accept a 40mm fan, search eBay for 12V 40mm fan and pretty much anything that shows up should be OK. Something like the Evercool should work REALY well. I just went for the cheapest and get great bridges etc...
On my Mendel there is already a fan output from the controller board so connecting to this worked like a charm with the fan turning on and off at the start/stop of printing. If you don't have a spare/fan output then just connect directly to the 12V supply.
Adjust the fan height from the build plate by adding washers under the mounting bracket and make sure there is enough clearance. The fan is shaped upwards to try to help ensure clearance.
When slicing you might get a few warnings, but just ignore them and see what you get. I often get strange slicer warnings and sometimes the print goes a bit off course, sometimes not. YMMV
The Mendel print head has been changed since I purchased my printer so this fan will only work on the older models. SCAD model is included so anyone with the newer head please feel free to update it and let me know how it works out for you :)