Square Gear

thingiverse

I searched online for square gear designs but couldn't find one on Thingiverse, so I asked how to design it in OpenSCAD. My basic input was a screenshot image edited with GIMP or other picture software. My first attempt was to convert the image to DXF using Inkscape, but OpenSCAD wouldn't import it. For my second try, I used a web service that converted PNG to DXF, but all of them required payment. This search was tedious because I had to register my credit card at the end of each online design process. My third attempt was to import the PNG directly into OpenSCAD, which worked only when the image size was significantly reduced (less than 256x256 pixels) and took a very long time to render (over 15 minutes). The outline of the object would be in pixels, so it wouldn't print well. For my fourth try, I shared a video of a square gear I found on YouTube: https://www.youtube.com/watch?v=En7OFIyMD-c. I also provided a download link for a PDF: https://goo.gl/F0db5J. I used a small software called OpenSCAD Contour Tracer to help me design the gear. This tool is available at http://dpruimboom.magix.net/public/ and has a YouTube tutorial at https://www.youtube.com/watch?v=QvL4TxJB4LU. Although it's no longer popular, it works well on Linux systems with Wine installed. Once I had the OpenSCAD script, it was easy to continue designing the gear. Additionally, OpenSCAD can export 2D elements as DXF files, which is another way to convert PNG to DXF. My license for this design is Public Domain because it's not an original idea. Since I'm unsure about the license of the imported data, I'll mark it as Noncommercial. Edit: On August 9, 2019, I found more instructions for using Inkscape with OpenSCAD at https://en.wikibooks.org/wiki/OpenSCAD_User_Manual/Using_the_2D_Subsystem#Rotate_Extrude. Scroll to the last paragraph for more information.