It has been a little while since my last wind turbine post because we have been working on the house a bunch lately…mostly landscaping the front yard. I should be able to get back to work on the turbine here again soon. I ‘ve been thinking about what I have left to do though and it is not that much really.
I ‘ve been thinking about where I can set this turbine up in order to test it. We have been thinking it would be nice to fly it at a friends house in Toas but that is not looking like such a good option now. His off-grid system is a bit small and a different voltage from the 10’ turbine stator. I built this wind turbine for a 48 volt system, which has become kind of the standard for battery banks. My friends batteries are wired for 12 volts. Down the road, when I have the building of this type of turbine down, I would like to look for a small piece of land and use this turbine to power a small cabin on it. But, right now I just need a place, prefereably near by, to test it out and make sure that this design actually works well.
Anyway, here is my list of things I have left to do on the first turbine…
1. Finish the tower stub. The stub needs to be cut to size, reinforced at the bottom, and cleaned up since it is very rusty. I might as well go ahead and build the tower stub for the second wind turbine while I’m at it. I also need to order a few bronze or plastic bushings for the yaw bearing. I think the sides of the tower stub will be covered with a piece of 2 inch PVC to protect the steel along the sides of the tower stub. I’m not sure this is the best material for a side bushing, but will give it a try.
2. Put a couple of layers of boiled linseed oil on the wooden parts of the blade assembly and tail. I also need to quickly make sure the blade assembly actually fits on the alternator. I think the 1/2 inch stainless threaded rod is plenty long but need to double check. I used 3/4 inch disks instead of 1/2 inch so it might be tight.
3. Order flat plastic stock for building a new stator mold. I need another one for building the stator for the second 10′ turbine. I need 2 pieces of 18″ squares of plastic that are 1/2 inch thick.
4. Test alternator RPMs using the new laser tachometer. I quickly tested it out and it looks like the cutin is at 130 RPMs for 48 volts. This is already a bit under the RPMs that the Homebrew Wind Turbine book says it should be. The shorter blades will probably cause it to hit this RPM too quickly. Perhaps I will add washers to increase the air gap distance in the alternator. I think the air gap will need to be larger since the blades I am using are shorter. If the alternator over powers the blades then it will not spin up fast enough to avoid stalling in low winds.
5. Finally, I need to figure out the best way to protect the steel parts. I would like to powder coat the entire thing, but I hear that is very expensive. I will call around but it is probably cost prohibitive. So perhaps I will try to call some automotive body shops and see if they can paint it for cheap using the last bit of paint from a run. If I can’t find someone else to paint it I will just paint it myself with steel etching primer and acrylic enamel paint.
Also, here are a few posts on the www.fieldlines.com discussion forum that I posted in the last couple of weeks or so…