Also, for most rapid prototyping processes and materials, the minimum
feature thickness is 0.020. Anything less than this and features will
Simply explained, a stl file is a format used by Stereolithography software
to create information needed to fabricate 3D models on Stereolithography
machines. In fact, the extension "stl" is said to be resulting
from the word "Stereolithography."
In short, a good stl file must conform to two rules. The first rule
states that adjacent triangles must have two vertices in common. Second,
the orientation of the triangles (what side of the triangle is in
and what side is out) as specified by the vertices and normals must
agree. If either of these two criteria are not met, problems exist
in the stl file. Minor gaps and inconsistencies can usually be fixed
by specialized STL-handling software. More significant problems usually
require going back to the original CAD model for modifications.