Prusa MMU2 assembly body fan

thingiverse

I recently upgraded to modified 42mm stepper motors on my MK3 using a standard 40mm fan. Following this, I conducted further testing with an infrared thermometer to monitor motor temperatures. All motors on both the MMU2 and MK3 were subject to temperature checks. The thermometer indicated an error of approximately 10 degrees Fahrenheit. Without the fan, the right-side motors on the MMU2 stayed in the mid-90s Fahrenheit, while the left drum motor exceeded 100F. Meanwhile, the Z steppers maintained a temperature around 101F and the extruder motor reached a scorching 120F. For comparison, I also measured temperatures on my MK2S, where all motors were running over 100F. The extruder motor proved to be the hottest at around 110F. Upon activating the fan on the MK3, the temperature of the drum stepper dropped to 94F. It's worth noting that the cooling fan adds a vibration to the machine, causing it to vibrate down to its legs. After updating to firmware version 1.0.2, I noticed significant improvements in motor temperatures. The cooling fan now appears unnecessary and will be removed from my machine. However, if you believe your setup necessitates the fan's assistance, I recommend giving it a try.