Cooling fans

The effect of the cooling fans depend where the blow.

Blowing to the nozzle might be necessary if a peak is printed and the filament can not cool down due to having the nozzle almost at the same place and having a small printing area. Slicers allow to control such fans fan depending the time the slice needs to print the surface. An other trick would be printing multiple parts so the nozzle moves away to the other part for some time.


Cooling fans might cool so well that the extruder does not reach anymore its temperature (or the temperature sensor) and the printer firmware as marlin report an error and stop printing.

Slicers as Slic3r have a parameter to set maximum fan speed.

Cooling fans are also used on extruders to keep the filament to be printed on a low temperature to not get damaged when it runs over its hobbed bolt and reduce oozing when the filament gets retracted to make a position move without something to be printed.


Such colling fans need to be permanently on during printing


If cooling fans for the extruder are off the filament might become too soft on the hobbed bolt and could jam the extruder badly.

Linurs startpage