Slic3r
Because the secondary extruder will be dormant whilst the first is
working, and vice-versa, it is important that the material is sufficiently
retracted to stop oozing. As with the regular retraction settings (see p.89)
the Length options is measured from the raw filament entering the extruder.
Assigning Filaments
When a printer profile with multiple extruders has been selected the Plater
tab allows the selection of a different filament for each extruder.
Figure 2.45: Plater with multiple filament options.
Assigning Extruders for Single-material Objects
For single material prints, where the secondary extruder is to be tasked with
a particular extrusion, the Multiple Extruders subsection of the Print
Settings tab gives the ability to assign an extruder to each extrusion type.
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