STL Import for SpaceClaim is a Stereolithography (.stl) file import add-in for SpaceClaim®. This add-in gives SpaceClaim the ability to import polygon mesh data from ASCII and Binary STL files. STL Import for SpaceClaim reads polygon mesh data stored in STL files and imports it into SpaceClaim. A polygon mesh in a STL file is comprised of a set of triangular faces. STL Import for SpaceClaim creates trimmed planar surfaces for each triangle and knits them together to create a solid. The solid is then cleaned up so that adjacent coplanar faces are merged in single trimmed planar faces. If the polygon mesh is closed (i.e. it does not contain boundary edges) then STL Import for SpaceClaim will create a closed solid feature, otherwise an open surface will be created. STL Import for SpaceClaim is very easy to use. It adds new commands to SpaceClaim. Once installed, it automatically loads itself into SpaceClaim and adds a new ribbon bar to SpaceClaim called "STLImport" containing the newly added commands. The 'STLImport' ribbon bar consists of the following commands: Import - Import a STL file. Help - Display the STL Import for SpaceClaim help file. Register - Register your copy of STL Import for SpaceClaim. About - Display the STL Import for SpaceClaim About box. The STL File Format The STL file format is the Rapid Prototyping industry's standard data transmission format and is the format required to interact with stereolithography machines. Stereolithography files contain solids which are made up of 3 sided facets. STL files may be ASCII or binary data, although binary is far more common due to the resulting size of the CAD data when saved to the ASCII format. A STL file describes a raw unstructured triangulated surface by the unit normal and vertices (ordered by the right-hand rule) of the triangles using a three-dimensional Cartesian coordinate system. Many CAD systems are able to output the STL file format among their other formats, but ver