Newbie dumb questions

[fred_dot_u]

I have a BCN3D Sigma dual extruder and the unused extruder remains cold. It can be empty or contain filament, but you don't want stagnant filament in the nozzle at extrusion temperatures. It will degrade very rapidly.

Nozzle alignment with respect to the bed is critical. There should be a means to adjust and/or calibrate for mechanical differences during the manufacturer and assembly.

[crisson]

Thanks for the great information, FRED_DOT_U. I will probably start out with one color PLA and didn't know what to do about the extra extruder/nozzle. Now I do. Thanks.