The Samara Wind Turbine - With And Without Tubercles
You can find a video about this here https://youtu.be/U13lU-Y6khc
to finish it you will nee 1 x 200mm by 8mm steel rod, 2 x 8mm washers and 2 x 22mmOD, 8mmID 7mm thick bearings - they are skater bearings