Summary

This creates a fan mount and nozzle for a Mini Kossel

I wanted a print cooling fan for my Mini Kossel that used a squirrel cage fan mounted above the effector. This is my solution.

Instructions

Vitamins:

(1) M3 nut
(1) M3x25mm bolt
3" of 18mm inner diameter flexible hose. Used medical air hoses work great. Just ask your local medical supply store for a used CPAP mask hose (not the long one that goes to the machine, the one that attaches to the mask - they'll know. ;)
(1) 12v 50x50x15 squirrel cage fan
A bit of wire to wire in the fan to the part fan port on your RAMPS (or equivalent). Don't wire it to main, you don't want this puppy running 100% all of the time. It will cause extrusion failures and other unpleasant things.

The height of the .stl is 64mm as measured from the top of the effector. To change this, edit the .scad file and modify the call to fan_duct().

Instructions:

Print each component.

Note: You can print the fan mount in PLA, but you should print the nozzle in ABS.

Note: the nozzle is 63mm tall, which mounts to the top of the effector. Measure the distance from the top of your effector to the bottom of the heater block on your nozzle. If this is 62-64mm, you're good. Otherwise, open the .scad file and change the height as needed.

Insert the M3 nut into the mount. If loose, use a bit of super glue to hold it in place (you won't be able to get to it during installation).
Secure the fan to the mount using zip ties.
Slide on the hose to connect the mount and nozzle.
Remove the rear-most bolt from your effector holding the hot end in place (or whichever point you want).
Assemble the fan and secure the bolt.
Wire the fan to your electronics board.

Mini Kossel Part Cooling Fan