Why is 3mm filament the default in the firmware?


I was looking at the SM firmware on Github and noticed that in the configuration file the default filament size is 3.00mm (see below).

Out of interest why has it been set to 3.00mm? I checked the same file on the Marlin repo and it defaults to 1.75mm which means SM team has intentionally changed it.


That relates to volumetric extrusion mode which is used by almost nothing.

If you’re interested in configuring a slicer for volumetric extrusion mode make sure and override that with the appropriate settings first.

Also git blame is a thing and no, snapmaker did not change that. Marlin changed it more recently after snapmaker diverged.

Bloody hell, that was a quick reply :slight_smile:

Thanks for the info Brent.


This is the default setting in Marlin firmware code and the firmware developer did not change it. Snapmaker does not have the filament width sensor, so this diameter does not matter.