Glossary
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There are a number of causes of such a mismatch of plastic
extruded, but it generally is the result of the input fila-
ment diameter not matching what the slicer expected, or
the steps per mm for the extruder being incorrect. By care-
fully measuring your filament diameter, and then checking
that that value is properly entered in the slicer – for a
Polar3D printer, this means properly entered under the ob-
ject’s
, “
BASIC
”, “
– you can generally prevent over- and under-extrusion from
occurring. (But note that poor quality filament whose di-
ameter varies can cause intermittent over-extrusion and
under-extrusion.)
See also
&
PLA
PLA (PolyLactic Acid) is a biodegradable plastic, typically
made from renewable raw materials such as cornstarch or
sugarcane. Besides 3D printing filament, other common
uses are for plastic cups and plastic water bottles.
See also
polar coordinates
Polar coordinates describe two-dimensional location via ra-
dius,
r
, and angle,
θ
. Compare with Cartesian coordinates,
which instead describe two-dimensional location via
x
and
y
coordinates. The Polar3D printer uses polar coordinates
at the hardware level, which has several advantages; see the
Polar 3D video “WWBD - Polar is Better”
Does this mean that you or your students need to use or
understand polar coordinates? No! The Polar3D printer
expects industry-standard
.stl
files, which describe loca-