Hi
Today in the UK we had enough wind to drive my 5ft mill, based on a modified car alternator, fast enough to see around 2A into a test battery. 600 to 700 RPM. The thing was not too noisy, and seemed quite happy. I went back into the shed to watch the meter, its the first time I have ever seen the thing actually charge, I was quite happy watching the ammeter, when I heard a bang...... Went outside and I only had 1 blade left on the mill.
Then I saw the branch at the bottom of the pole. It was from a neighbours Laurel Tree over 30ft high. It had come from the top of his tree missed another garden and hit my blades it was about 1 1/2 inches thick and about 4 ft long with a big bunch of leaves on the end.
I had taken as many precautions as I could with making my mill, even ran the blades up on a motor at a speed greater than the alternator needed to charge, I have a very poor site with the house and a number of trees, so the mill was mounted that if there was a problem there was only a window less brick wall or trees for the bits to hit, I never expected to have bits coming at me from the other direction.
Good point I didn't have to look far for the blades they were still in the bit of tree, and I still have one blade that I know is a good profile as a template...
Brian
