LulzBot TAZ 5 - Holes Made through Polygonal Segments

Slic3r
radius shorter. A compensation algorithm
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was proposed by Adrian
Bowyer, and it was implemented in Slic3r some time ago but many users
complained about holes being too large – it was removed thereafter since
smaller holes are better than larger holes since they can be drilled.
Curves are approximated by polygons
STL les only contain meshes composed by at triangles, so its planar
sections can only contain polygonal shapes. For example, a circular hole is
approximated by a polygon:
Figure 2.68: Holes made through polygonal segments.
Increasing the number of segments in your CAD before exporting the
STL le will help reducing the error. OpenSCAD users might want to
use the polyhole() function developed by nophead
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that calculates the
optimal number of segments.
Filament tends to cut corners
Since curves are approximated by polygons, there are sharp vertices at their
vertices. However, plastic tends to make rounded corners, thus reducing
the internal area of the hole even more.
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http://reprap.org/wiki/ArcCompensation
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http://hydraraptor.blogspot.it/2011/02/polyholes.html
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