Summary Only works with this mod http://www.thingiverse.com/thing:300335/#files And this mod http://www.thingiverse.com/thing:304213 Fan mount for the modified UP Mini extruder stepper. Attached with two magnets that are epoxied into the fan mount. two steel washers are epoxied to the stepper mount and wind barrier. Instructions Only works with this mod http://www.thingiverse.com/thing:300335/#files And this mod http://www.thingiverse.com/thing:304213 Watch for interference of the fan and printer housing when the extruder is far right. Attached with two 1/2" dia x 1/8" thick neodymium magnets that are epoxied flush into the fan mount. two 1/2" x .090 steel washers are epoxied to the stepper mount and wind barrier. Look at the drawing for more information. The 12 volt 15 or 20 mm fan is wired directly into the existing fan wires. The fan pushes air away from the stepper. The fan bolt hole dimensions are 32mm between bolt centers. You will need to tap four 3mm x .5 holes in the fan mount and buy some 3mm-.5 x 10mm screws to mount the fan to the fan mount. You may need to lengthen your heater wires.