Good Morning,great weekend
We worked like beavers pretty much all weekend. I don't mind mentioning the results are magnificent. 1.6 meg of images follow,and these are all shrunk down to less that 50k each, for the most part. So sorry for sucking your bandwidth down. I hope you think it was worth it.
One of the many things I really love about the home built wind turbine, is the wood and the linseed oil.
This set of blades are made from Western Red Cedar, a light-weight wood. This is the wood recommended in Dan Bartmann's and Dan Fink's Homebrew Wind Power Book. I finally found some this Winter while we were in Santa Fe during Nell's surgery on her hand. Yeah I went to Home Depot while she was under the knife. I was back on time,and she did fine. It gave me the hour or so I needed to sort through the hundred or so boards of Cedar they were selling as fence supports. They were rough cut two by fours,which I cut down to two by two inch sticks and laminated using all of the wood clamps we owned and more that we bought.
Kevin Murphy is at the helm of CNC (machine) He also designed and created these blades.
Adam Lucero came out on Sunday and really helped get the blade project moving along. We needed to make certain the three blades were precisely the same. We accomplished this by setting all three on top of one another and penciling differences. Using a electric orbital sander with 150 grit sandpaper we trimmed and feathered edges. All in all the blades were very close in shape, length and width.
Blades-Adam-Brian-7-17-2011 While we sanded the blades seemed to become more substantive. Little cracks in one blade turned out to be outside the pattern edges. With every stroke of the sandpaper the blades shaped up. We did have to pay close attention to the grain and always sand away from it, because the knife edge along the trailing edge would instantly grab the sandpaper and tear into the grain. I don't know if you can see the grain or how much you know about wood grain,but it the above image the direction of the grain changes about three quarters of the way to the tip. At that point using a small piece of sandpaper in hand we would stop in the direction of sanding and go in the other direction. To me it felt like sharpening a sword; long gentle and accurate stokes.
Blades-Adam-Brian-7-17-2011 First coat of linseed oil, wow, the cedar is gorgeous
Blades-Adam-Brian-7-17-2011 Adam paints on the first coat of 50/50 mix of Linseed Oil and Gum Turpentine
Blades-Adam-Brian-7-17-2011 "Get a before and after shot," Adam said. Yeah man!
Blades-Adam-Brian-7-17-2011 We tried to not get all OCD on the finish. Still it came out very fine. One thing about the cedar is it is quite soft and doesn't take long to remove a lot of material. One of my concerns with this set of blades is the thickness, so I did not want to run the grain down to remove all of the router cut marks.
Blades-Adam-Brian-7-17-2011 First coat of linseed oil soaks in quickly. I just love the gentle and natural feeling curves Kevin managed to make a cold hard reality of a machine produce.
Blades-Adam-Brian-7-17-2011 Above you may be able to see the fluctuation in the grain height,this is because the cedar is so soft
Blades-Adam-Brian-7-17-2011 More router marks,no matter,it still looks great and it won't hinder performance,these blades will slice through the air,with the greatest of ease.
Stator-Adam-Brian-7-17-2011 We struggled with the stator for quite a long time,We got it centered on the hub several times,as seen above, but when we tightened the nuts it went right back to badly offset and rubbing. We straightened the supporting althread bolts,because of concerns on the Otherpower forums that the nuts may come loose I think they may be correct with those concerns, because why else would the stator keep moving even before we attempted to tighten the nuts?
Stator-Adam-Brian-7-17-2011 –Certainly something was amiss with the neato coolio super duper design modification I had created a few weeks ago in an attempt to create a system to move the stator back and forth and up and down to center it on the hub. If it moved this much right in the shop,we sure can't trust this method to stay in place for months and months up in the weather.
Stator-Adam-Brian-7-17-2011 cleaned up stator,more or less in position against the magnet rotor
Blades2-Adam-Brian-7-17-2011 We didn't do too much to the blade tips either. They're all about the same length: five feet from root to tip.
Blades2-Adam-Brian-7-17-2011 Unfortunately the camera picks up every imperfection,in reality those router marks can not be felt when running the fingers over the grain. The feel is all that matters aerodynamically speaking
Blades2-Adam-Brian-7-17-2011 I love wood grain, so I'll let the next pictures speak for themselves, besides Buddy our new puppy has had me awake and up since 4:30 and now I'm ready to fall asleep,but I need to get ready for work
I know huh?
Brian Rodgers
