My friend alex_joni on the #emc channel told me there is no free software to convert from STL to DXF formats. I figured it would be pretty easy so I whipped this up for him.
STL stands for Stereo Lithography and is a (very verbose) file format for describing triangular polygons in 3D space. This program converts these into AutoCAD's 3DFACE entity. AutoCAD's DXF is silly in its own ways but is a very old format that can be read by virtually anything.
stl-to-dxf requires python but no special python packages. Simply run it like this:
python stl-to-dxf.py < file.stl > file.dxf
... later ...
I guess there are ASCII and binary STL files. This program works for ASCII files.
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