MK3 / MK3S / MMU2S small Extruder Cooler with diverted airflow

I wanted an extruder cooler for my MK3S to stop filament jams, that would fit snugly and not blow air down onto the heatbed.

Unnecessary cooling of the heatbed can interfere with printing of materials prone to warping such as ABS/ASA.

All coolers I could find with diverted airflow were loose-fitting. The "MK3 / MK3S / MMU2S small Extruder Cooler" by KalleKnall is a great shroud that fits snugly onto the extruder motor, but it has no alternative airflow options. Therefore I have modified it with baffles at the bottom to stop air coming out underneath, and angled side vents to push expelled air upwards.

Print instructions

Print upside down using PETG. I found the cable guide superfluous as the fan cable can be routed through the MK3S's own cable guide on the left of the extruder assembly. The fan wiring can then be channelled down through the cabling into the EINSY case. In my case, I powered a 5V fan from spare ground/5V pins on my unused MMU2S connector.