I uploaded some pics, one of them is of some rocks after being tumbled for about 10 days. It's vary wind here during the day and the prop was spinning like a Tasmanian dust devil. The ratio between the prop and the vessel containing the rocks is about 50 to 1. It has to be high if you want it to start from a dead stop an from a slight breeze. I took a cool video of it running before it was discovered and taken away by the park rangers! You see I had no place to put it, so I tried setting it up in a secluded spot in the hills around here, not so secluded as it turned out. Will upload video if possible.