H-Darreius wind turbines ( VAWT ) !

[SparWeb]

This really reminds me of the glider competition I joined in college.  We made an aircraft glider with a 3 meter wingspan to carry a heavy payload.  The competition was to keep the glider aloft for as long as possible.  The wings of that glider looked a LOT like your VAWT wings!

[topspeed]

This really reminds me of the glider competition I joined in college.  We made an aircraft glider with a 3 meter wingspan to carry a heavy payload.  The competition was to keep the glider aloft for as long as possible.  The wings of that glider looked a LOT like your VAWT wings!

Yes thanks again.

I am putting all my effort to make this as perfect as I possibly can without industrial level tools.

This has to be fast too...otherwise it will stall at high winds speeds because of the TSR demand.

[Mary B]

This really reminds me of the glider competition I joined in college.  We made an aircraft glider with a 3 meter wingspan to carry a heavy payload.  The competition was to keep the glider aloft for as long as possible.  The wings of that glider looked a LOT like your VAWT wings!

Reminded me of my RC airplane days and the 6' Piper Cub wing I built(and rebuilt after crashes!) an aluminum main spar ran the full length then the rest of the wing was built off of it

[SparWeb]

That's still the norm with many homebuilts, Mary.
Big aluminum tubes with relatively thin wall are a simple starting point, then the ribs slide down from the end. 
Some get fancy, and use carbon-fiber spars instead.  I'm not so keen on that because cheap CF tubes are very porous.
Either way, the tube fits into a round socket and voila the wing disassembles for transport on a trailer.
I still see a lot of these at the EAA airshows.  I don't go as often as I used to, but funny thing, the true classics are still there.

[topspeed]

That's still the norm with many homebuilts, Mary.
Big aluminum tubes with relatively thin wall are a simple starting point, then the ribs slide down from the end. 
Some get fancy, and use carbon-fiber spars instead.  I'm not so keen on that because cheap CF tubes are very porous.
Either way, the tube fits into a round socket and voila the wing disassembles for transport on a trailer.
I still see a lot of these at the EAA airshows.  I don't go as often as I used to, but funny thing, the true classics are still there.

Simplicity is one goal.

Unfortunately the 34 m/s wind needs TS of 490 km/h speed for the wing...it cannot be a Piper Cup wing anymore.

[MattM]

What's it going through in one rotation at that velocity, 2-3g then the same inversed?  Piper Cub wings can handle it.

[topspeed]

What's it going through in one rotation at that velocity, 2-3g then the same inversed?  Piper Cub wings can handle it.

Old straight wing clocked 300 Gs......counting using weight and speed on a circular path.

By old I mean the green smaller prototype...from 2018. The yellow wing system suffered from being too big in solidity and having too big generator for the size. I fixed this now by increasing the wind capture area almost 3 x.....and dropped the solidity by 35%....or thereabouts.

I figure the new can do 500 Gs....computational Gs.

[topspeed]

I have put a lot of effort to keep my work space clean lately...it also rises the spirits there when everything is not covered with 1 mm layer of fine grain dust.

Here the aluminium dust is sucked away by a new vacuum cleaner.

[topspeed]

I am one step further on my 4th test wind mill.

[SparWeb]

Looks nice - will there be a longeron at the trailing edge?  I don't see it there yet.

If you are avoiding that, to make a sharp trailing edge, I can show you some RC model airplane tricks to keep the edge from wrinkling.

[topspeed]

I have 1 mm plywood covering...no need for the longeron there.

[Astro]

This looks awesome. Very nice work indeed.

[taylorp035]

Those are some nice looking support structures.  I'm assuming the skin is going to help with the bending forces once this thing really gets spinning.

[topspeed]

Yes skin is very important structural component in this.

[Astro]

Yes skin is very important structural component in this.

 What is your projected rpm? I wish I could find the video again, and I am sure some of you have seen it, but I saw one made on the other side of the pond, that was huge. It had to have been 20ft across and had 5-8 blades or so, I understand they were promoting their product design, but they did a good job. They had it mounted on a trailer and moved it to several spots and the thing just spun and spun. It was as close to a constant velocity (in different situations) vawt as I had seen to date. (outside commercial ones). It was part of my whole design process. How I just want one that sits there and turns if the wind is 10 or if it is 25. That and watching the big hawts around me do that, made me think of the turtle and the rabbit race. Sure maybe I can't put out x amount per day, but averaged over the 168 hours in a week, I am hoping I can compete with a good hawt, if not edge above it in the long run.
 The slower it spins the less important the selection of blade skin is. Don't you think?

[JW]

What is your projected rpm? I wish I could find the video again, and I am sure some of you have seen it, but I saw one made on the other side of the pond, that was huge. It had to have been 20ft across and had 5-8 blades or so, I understand they were promoting their product design, but they did a good job.

Wow this is a 7 page post

I have some personal projects  that I'm working with on external combustion will post these.

Cooking some shrimp tonight. My camera needs to be replaced, will get a new one. 

[Astro]

What is your projected rpm? I wish I could find the video again, and I am sure some of you have seen it, but I saw one made on the other side of the pond, that was huge. It had to have been 20ft across and had 5-8 blades or so, I understand they were promoting their product design, but they did a good job.

Wow this is a 7 page post

I have some personal projects  that I'm working with on external combustion will post these.

Cooking some shrimp tonight. My camera needs to be replaced, will get a new one.

 I need to hurry up and get this project done, as I have a couple more in mind as well. It is supposed to get up to 40 here in a day or two, I think I will use that day to get some wood cutting and such done out in the shop.

[JW]

Right- on.

[topspeed]

Yes skin is very important structural component in this.

 What is your projected rpm? I wish I could find the video again, and I am sure some of you have seen it, but I saw one made on the other side of the pond, that was huge. It had to have been 20ft across and had 5-8 blades or so, I understand they were promoting their product design, but they did a good job. They had it mounted on a trailer and moved it to several spots and the thing just spun and spun. It was as close to a constant velocity (in different situations) vawt as I had seen to date. (outside commercial ones). It was part of my whole design process. How I just want one that sits there and turns if the wind is 10 or if it is 25. That and watching the big hawts around me do that, made me think of the turtle and the rabbit race. Sure maybe I can't put out x amount per day, but averaged over the 168 hours in a week, I am hoping I can compete with a good hawt, if not edge above it in the long run.
 The slower it spins the less important the selection of blade skin is. Don't you think?

Since the radius is now greater and generator has a gear I need only 100-200 rpm.

Next I am onto the wing tips. That will expand the span by 10-15 %.





The 1 mm ply covering with surface handling will double the weight of the wing.

It is just under 1,5 kg now ( at 3 lbs ).

[Astro]

I think we are all excited to see it up and turning in the wind.
What are you going to seal it with to keep moisture out? 3 pounds is lightweight for a blade that size, so you have some options when it comes to trying to preserve them from water.

[topspeed]

I think we are all excited to see it up and turning in the wind.
What are you going to seal it with to keep moisture out? 3 pounds is lightweight for a blade that size, so you have some options when it comes to trying to preserve them from water.

I use normal varnish or such coating lacquer kinda glossy liquid that makes the surface slippery too. Hefty amounts of it too...so that it look like glass when dried up.

[Astro]

I think we are all excited to see it up and turning in the wind.
What are you going to seal it with to keep moisture out? 3 pounds is lightweight for a blade that size, so you have some options when it comes to trying to preserve them from water.

I use normal varnish or such coating lacquer kinda glossy liquid that makes the surface slippery too. Hefty amounts of it too...so that it look like glass when dried up.

 Yeah waterproof means different things depending on where you are. Here in the US, you can build an untreated pine fence in the south west and it will last for years. In other areas, it will rot away in a year.
That is the thing about building these things, there is a million ways, because each one of us had different circumstances to deal with.

[topspeed]

About 6 years ago I was talking to a boat builder in southern Finland who claimed that wooden boats last forever as long as the surface stays unbroken....or the structure in general.

Wonder if the poor maintenance or the holes for attachments are the cause for a rot.

[Astro]

About 6 years ago I was talking to a boat builder in southern Finland who claimed that wooden boats last forever as long as the surface stays unbroken....or the structure in general.

Wonder if the poor maintenance or the holes for attachments are the cause for a rot.

 Well he might be right. I have seen lots of old wooden boats. I mean hey look, if wood rotted away so easy, we would not be living in wooden houses. My grandparents always said, keep a good roof on it and it painted and it will last forever. People just do not like the work of maintaining things these days.
 I put a couple coats of linseed oil on my stator mold today and I was thinking how my dad who owned semi trucks used to linseed the wooden decks of the flatbed trailers. Granted that is a hard wood and not pine or spruce, but really it is just a matter of saturation when talking weather proof and not strength. We always did it in the middle of summer when it was hot. Idk maybe because the pores of the wood open up in the heat? (I brought my mold in the porch where it is warmer for the second coat).
Strange how we remember lessons that we did not even know we knew.

[MattM]

Be aware that rot is microbe activity, something much slower in Finland than at the equator.

[topspeed]

Thank God the clamps were invented before my time.

[Astro]

I am starting to think you enjoy the whole blade building process. Lol. The closer I get to when I will get to that part and start buying stuff to do it with, the more nervous I get.

[topspeed]

Yes I enjoy it very much as each time I have a problem I just stop it....until I have an answer how to go forward.

[SparWeb]

HAHA

You are the clampmaster!

[topspeed]

Clamps are still in need, but I have to advance one surface at a time.

Applying pressure on the skins.

Wing tips are almost ready.

[topspeed]

I am currently finishing the 3rd wing half....two are raw finished...in the pic ....and wing tips painted.



Yellow one below is the old wing.



Here is the third one receiving pressure.

[Astro]

Impressive, I can't wait to see it flying!!

[topspeed]

Thank you Astro....I blew the last attempt on this....now I am trying to keep it dead center and use all the knowledge and concentration I possibly can.