OpenScad Helix for custom 2D profile and many thread types

thingiverse

This is a script for OpenScad to create a helix. Well, at least "half" helix. I needed a fast thread generator for printable buttress threads. So here is the result. It is faster than intersection/difference based code and creates a single polyhedron for the complete thread. Of course, the OpenScad code could be beautified and probably be written on one line, I know. If you find a corner case which does not work...I must say, at the moment I have other projects and I just wanted to give something back to the community. But maybe I have time later on, so if you report errors here that would be great. Before reporting please check out the TODO list in helix.scad. You can define your custom tooth profile map of your helix if the already prepared ones in threads.scad are not ok for you. A map is a vector with x/z elements describing your profile. Check out test_rope_thread() in thread_test.scad and "rope_xz_map" in threads.scad. If you want to "play" with the scripts, download all three scad files into the same directory and open test_threads.scad in OpenScad. There, you can adjust $fn and uncomment different test/threads (line 74). I'm terribly sorry, but there is no help file for the parameters. But the code is commented. Threads already implemented (not exact ISO specifications): Metric threads Square threads ACME threads Buttress threads Channel threads (to "stick" something to another thing) Rope threads (for rope pulleys) NPT BSP (imperial stuff, tapered gas pipes) Meccano worm threads (Ha!) All can have a bore in the center (pipes or other purposes) All can have multiple starts All support internal(nut) and external(screw) with customizable clearance according to your printer's abilities. Very fast rendering, no "normalization tree" problems Would be nice to hear if it helped in your work and what you have created with it. Update 30.12.2016 : I wanted to mention another feature: If you want to export the polyhedron to your scad script you can uncomment some echo code in file "helix.scad" on line 2794 until 2801. Then OpenScad outputs the faces and points which you can copy/paste to your file. This way, you don't need to re-run the script every time while designing your own object where the thread is needed. Update 23.04.2017 : I removed "debug feature" which created incorrect threads for small diameters (around 3mm). Print Settings Printer Brand: RepRap Printer: Huxley Rafts: Doesn't Matter Supports: Doesn't Matter Resolution: 0.2mm Notes: I create buttress threads, so there is no need for support material, which works great.