I like to tinker and find interesting ideas all over the place. This one came from You Tube where a guy used a coil from a microwave turntable motor to generate electricity from a spinning ring of magnets. Well I make a lot of these CD windmills and I tear apart a lot of microwaves for the ring magnets and transformers ( for fractal burners), so I decided to make a prototype windmill to see if it would work.
The windmill is made with a 22 " diameter fan with 9 CD blades. I put 24 1/4" x1/2" rare earth magnets on the inside of the plastic hub- with alternating polarity. Right behind the ring, on the stationary platform, I have plastic block with 2 of those microwave motor coils each with steel core in the center and epoxied in. The spinning magnets in front of those coils put out an AC voltage- probably because the polarity on the magnets is alternating, But one coil puts out 13V and the other about 3v. with a spin by hand in the shop..and I don't know why. So I used the 13 V for the ring of 12 red LEDs I have right behind the fan and I use the 3V for the 10 LEDs in the tail. There are 3 red and 2 white in each half of the aluminum tail.
The brightness of the LEDs is proportional to the speed of the wind (fan). In low wind the tail does not light at all. The red tail LEDs are 2.2 V and the white ones are 5V so if the white ones glow, the wind is very high.
The windmill is 22" diameter and 18" long. I used a variety of material I had in the barn- lots of different plastics and polycarbonate, aluminum, brass and all stainless fasteners. I only had to buy the magnets and the LEDs
I made a You Tube video of it running this morning: https://studio.youtube.com/video/U75h_Q63kA4/edit Cheers, Jim p.s. I have a lot of process shots below:
Cheers, Jim ........................ Variety is the spice of life...............Learn something new every day
Thank you all for the nice comments! I'm pretty happy with the outcome. I did some research on windmills and wind generators and found that my tail should be about 5 1/2" longer for better directional stability. I'll do better on the one I have planned to generate 220 volts for home use.
Hi Alex, that indexer on the wood lathe is invaluable in many of the projects I do for equal spacing. I also have some discs that mount on the back of my 4 jaw chuck that will do 5, 10 and 7 equal spaces which I cannot get with the 72 hole wheel.
Hi Bigblackyeti. I checked the output of the coils and neither register much at all on DC voltage. But on AC voltage, one put out 3 volts and the other 13 volts with a fast spin on the bench. The wind spins it faster than I could and I get at least 5 volts on the one for the tail because it lights up the 5 v white LEDs when it is really moving. I have to put a new battery in my laser tachometer so I can measure the speed of the fan where it light up the different groups of LEDs.
Cheers, Jim
Cheers, Jim ........................ Variety is the spice of life...............Learn something new every day
