User's Manual Part 2

Glossary 278
ament to some other portion of the build plate where ex-
trusion will be resumed. Retracting (raising) the extruder
nozzle for non-extrusion moves helps keep the extruder noz-
zle from dragging or smeari n g extruded material while it is
being moved to its new position. 139, 176, 240, See ex-
truder
SD card
An S D card is specific type of memory flash card and is
used to convey print files to your printer without using a
USB or network connection. SD cards come in a variety of
sizes, ranging from a fraction of a gigabyte to upwards of
256 gigabytes or more. The term “SD” is an acronym for
“Secure Digital”.
shell
When a model is prepa r ed for printing by a slicer, the slicer
generates commands to print a solid exterior. The exterior
is typically printed by following the model’s perimeter. The
perimeter may be printed multiple times per layer, each
time inset from the prior pass. The final result can be
thought of as a series of nested shells, one inside the other,
from which ari se s the term “shell ”. With some slicers, you
contr ol the thick n ess of the solid exterior by specifying the
number of shells to generate. 220, 240, See also slicer
skirt
A skirt is an extra outline of material surrounding, but not
touching, the perimeter of a print object. A skirt is some-
times used to shield the main object from thermal drafts,