Created with stl_threads and other stl_cmds. Printed on my Makerbot Replicator 2. Read more about how this was created in my blog post.stl_cmd is a suite of command line tools for manipulating binary STL files. stl_threads can generate screw threads per the ISO metric thread standard. Unlike OpenSCAD solutions that perform many, many slow CSG operations, stl_threads directly generates the triangles necessary to represent the threads. Any resolution/configuration is pretty much instantly generated. This file was created with the following commands: Documentation for stl_threads. Outputs an stl file with male or female screw threads per the ISO metric screw thread standard.