Manually Operated Mechanical Fan

This hand-cranked fan is perfect for warm days. Rotating the hand lever engages gears that spin the fan at high speed. The gears have a 1:24.89 ratio to ensure a cool breeze; therefore, some force is required. Care should be taken not to concentrate force on the gear's center, as this could break the support column. It can be easily assembled from the 3D-printed parts as shown in the images. This device has been designed to be as compact as possible and is available in versions with and without an extended handle. Two different propellers in two different sizes are included. One version includes a ring to protect the hand but reduces the fan's efficiency. The propeller with the highest efficiency is the large propeller without the ring. However, caution is advised as it also presents the highest risk of injury! This model was inspired by the “Squeeze Fan Ruggedized!” by Xia Zhi, where the gear ratio was unfortunately too low. However, this model was completely redesigned and improved from scratch by me in FreeCAD to increase stability and efficiency. Only minimal support structures are needed.