The slicer programs will have a setting called "Layer
Height" on both the Slic3r and Creator software. On the
Afinia, it's called "Z Resolution." This setting lets you control
the thickness of each layer as it is printed. A setting of .1
mm to . 3 mm is typical, but the slicer software will allow
you to print thinner or thicker layers. The machine will
dictate the actual range of reliable layer thicknesses.
The layer thickness lets you set a balance between
resolution and print job speed. The thinner the layer, the
more layers that need to be printed, thus the longer the
print will take. Slic3r has an extra field called "First Layer
Height" that allows you to override the layer height on the
first layer. Creator has a more robust way of setting the
height on any layer. Referring to Figure 13, the top print
was printed at a layer height of . 25 mm. The bottom print
was printed at . 10 mm.
Perimeters are the extrusions that go around the
outside of the object you are printing. Figure 14 shows a
print that has two perimeters. The number of perimeters is
determined by a setting in the slicing software.
In addition to the number of perimeters, you can set
the speed to the outermost perimeters. Most of the time,
you will be setting the outside perimeter slower than the
others. The reason the software allows you to slow down
the outer perimeter is to create the smoothest, most
accurate profile possible. You can also have inside
perimeters like the ones shown in Figure 15. Some slicers
refer to these as small perimeters and give you separate
speed settings for these, as well. The Afinia software gives
you no control over the perimeters.
When you create a 3D print, it is rare that the interior
of the print is solid. You will set the percentage of infill
which will dictate the amount of plastic that is used to fill
the interior of the part. Referring to Figure 16, the print on
the left has a 20% infill, while the print on the right has a
10% infill. In Slic3r, you set the infill percentage as a
decimal number between 0 and 1.
In Creator, you use an actual percentage. The Afinia
software does not give you granular control over the infill
settings. You get four settings, ranging from almost solid to
sparse. Selecting the amount of infill is a balance between
weight, strength, and the amount of material you wish to
use in your print. The more infill you use, the longer your
print will take. Some slicers — like Slic3r — allow you to
select the actual infill pattern. Referring to Figure 17, the
pattern on the left is a rectangle which is supported by all
slicers. The pattern on the right is honeycomb which is only
supported by Slic3r.
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