Time for the next windmill

[taylorp035]

Yesterday, I tore apart my 3 bladed VAWT and brought it inside where I could work on it.  After listening to you guys and your general consensus of making the vawt a 2 blade, I decided to take the blades and place them in a two blade configuration on the floor.  I then stacked the 3rd blade on top of the other two and thought about making a 4th blade to make a taller 2 blade VAWT.  I quickly decided that the VAWT idea wasn't going to produce any electricity, therefore, no fun.  So.... back to the drawing boards

Today, I spent about an hour drawing up and doing the calculations for 48" HAWT.  The idea is to have 6 blades because my 50" windmill was very close to achieving my goal of having a reasonable 12v windmill, and the 50" had a hard time starting up.  I further went on to calculating the correct attack angle on the wind side for every 3" along the length.  Lastly, I calculated the airfoil height for each section, which I found that my old blades were way too thick.  Also, I think that my older blades were not angled properly at the tips, which was causing a lot of whooshing sounds and very poor performance over 15mph.

My new blades will make a 48" diameter and be 3" wide from 12" on in.  The tips will be 1.5" wide, from 18-24".  The 12-18" section will be curved (I think).  The tips are angled at 4 degrees, which I hope is a good number.
Based on a TSR of 6 and a cut in of 400 rpm, it should produce power at 9-10 mph.

Wood choice is either going to be ash or poplar.  I was thinking of cherry too because it is rather straight grained and fine, but it is also somewhat harder to cut.
Progress will start whenever I can get the planner set up to start with some square boards.

[Bruce S]

Well... IF you're wood carving on Horizontal blades are going to be anything like the Vertical in workmanship they should look awesome.

Those Vert blades you made looked close enough to be used for a young crate of red wine to age in.

Let the fun begin!!
Bruce S
 

[taylorp035]

Thanks bruce    I was seriously thinking of just making a 4th blade to have twice to windswept area.  I will put the VAWT blades in the corner with my other windmill parts and maybe I will use them in the future.

[Bruce S]

Thanks bruce    I was seriously thinking of just making a 4th blade to have twice to windswept area.  I will put the VAWT blades in the corner with my other windmill parts and maybe I will use them in the future.

You could do that while setting up the planner :-). IF you do tho, set the second set 90 degrees off from the others.

I don't know about using cherry wood tho, go with a good pine for the first round of cuts. At 48inches pine will be good and sturdy with minimal flexing.
Plus a bit cheaper per board feet. Cedar could be a good choice if you're worried about weight, plus it's naturally water resistant. 
Once you have the blade configuration dialed in then jump all over the Cherry wood.

With respect to the VAWTs swept area can be very critical to these. Weight can be a big factor due to the load on the bearings. What was the overall dimensions and weight of the Last unit minus one blade?
I think you'll find the 4 bladed unit one with a better start-up curve. 

[taylorp035]

With 2 blades, the VAWT would be about 24" dia and 20" tall, 40" with 4 blades.

I got my wood planned and I started on the first blade.  I chose ash for the wood.  So far it is cutting very well.

[taylorp035]

Number 1 is finished   As any person who has tried taking a good picture of a windmill blade, they quickly realize that it is not easy.  Blades 2-6 will most likely not materialize until next monday, as I work Thursday-Sunday.

[taylorp035]

Yesterday, I finished blades 2 and 3.  I found it takes exactly 2 hours per blade to make, but after making them, my hands were worn out from the draw knife and spokeshave.  I can't wait until it's finished   I still have my tower and tail from the last windmill, so assembly should take minutes, not hours/days. 

[taylorp035]

I completed blade #4 tonight.  I also got around to sharpening my tools, which should happened in the first place.

I also decided that I needed a new wooden hub, since my old hub was a piece of 3/4" plywood, which isn't even close to flat anymore.  At 100 blade passes a second during medium to high winds, it better be evenly aligned at the tips.

[taylorp035]

I finished #5 and I am halfway through making a new hub because the old one was not flat and it had way too many holes in it.  I made sure the holes were perfectly lined up this time for the blades
It is possible that it may go together later today.

[taylorp035]

Blade #6 is halfway done.  I went out and got the remaining necessary hardware to bolt my extra 3 blades on.

[taylorp035]

Sorry for the slow progress.  I am quite lazy right now.  Nothing takes the energy out of you like working 10 hour shifts at an amusement park ( kiddie rides should be outlawed ).  Yesterday I had to sign people in at a picnic for 10.5 hours, with only one half hour brake (10:30 AM - 9 PM).  Then it down-poured and I had to walk through 4" of water.  Next thing I know the dryer broke...  Monday is the next day off, so good things should happen then.

Would of been nice to have the windmill going this weekend b/c of the 30+ mph gusts.  Windy days are far and few between during the summer...

[12AX7]

Hi!

an "amusement park"   
that's gotta be up there in the "ten best" places to score in their trash heap!

ax7

[willib]

Hi Taylor yes they look good , if ya make the trailing edge as thin as possible it cuts noise to a minimum

[taylorp035]

an "amusement park"   
that's gotta be up there in the "ten best" places to score in their trash heap!

You would think so, but they don't really throw much stuff out.  Maybe sometimes they could have a trashed 10-50 hp 3 phase motor off a ride...  They have a 200 hp motor in the roller coaster
Most of the garbage is food related.

Hi Taylor yes they look good , if ya make the trailing edge as thin as possible it cuts noise to a minimum

Yeah, I was making a point to make my blades thinner.  My old blades were way too thick for their size.

[taylorp035]

Here are some updated pictures.  I should be finished around lunch time

[taylorp035]

   I finished the blades and I mounted the hub on to the flywheel.
















It is not very windy today, so maybe tomorrow I will get it on the pole and watch it spin.  I did hook it up to 12, 18, and 30 volts and watched it spin.  Balancing only required switching two blades.  The tips are within +- 1/16" for length and +- 1/8" in and out.

It was fairly balanced at 12 and 18v.  30v was ok, but it did shake a bit, but that was a good 1000 rpm.

Here is a video of it with it hooked up to a 12v battery.
http://www.youtube.com/watch?v=5Ggz-llidZE

[wpowokal]

I see one major flaw. your workshop is far too clean

allan

[taylorp035]

I even found some furniture grade mahogany for the hub

Wednesday is calling for 17 mph winds from the SW, which should be good since I am not working that day 

[taylorp035]

I got the windmill out on the tower.  Unfortunately, a pop up rain shower came along and got it all wet, which I was trying to avoid.  Plus, it hasn't been very windy at all, maybe 5 mph.  Plus, the wind direction is from the west, not the south like the weather station said, so it hasn't turned all day.

[ghurd]

Those blades are never going to work.
I suggest disassembling, carefully packaging, and shipping them to me for proper disposal.   
G-