Summary I am working on a 3D print windmill and wind tunnel. These models are the results of my testing done in the period of June 2014 till October 2015. 2015_10_11 Updated the files with a better printable model and the shell version that shows possible ranges of its wings. Print Settings Rafts: Yes Supports: Yes Resolution: 0.2 mm or less Infill: yes Notes: The Mill is difficult to print in ABS or PLA ! Support must be set at 45 deg for best results. If you have a a printer that suffers from warping take care that you mount the perf board well with extra clips. Post-Printing A small 7 cm diameter version How I Designed This The idea for a wind mill came up a long time ago thanks to my experiences with kites (speed-wing type), and other hobby's like windsurfing. More inspiration came from Mc Escher's Spheres and my love for bio-metric 3D design and the 3D printing revolution. I tried to fit it in more with nature by using the mathematical spiral formula and diverse shaping of it's wings. The first results show a 30 cm diameter type that can deliver electricity at wind speeds over 3 bf (to load a smartphone battery for example) To make it work I used two nails without their heads or other strong metal that fits tight in the holes. The mill itself must be able to turn free. (use a drip of oil) I will upload a version with the E motor mount soon. h h