Just a Progress Report

looking good fish! :)

i gotta say i admire the way you tend to think things through a "bit" while working out a project!

no problems getting to your photos.. looks like you grabbed the "Direct Link" (option two) if we want the picture in the forum thread the "IMG Code" (option five) will do it.

looking forward to the next installment.

cheers, dave

monolithic stiffening principles are alive and well!

no problems getting to your photos.. looks like you grabbed the "Direct Link" (option two) if we want the picture in the forum thread the "IMG Code" (option five) will do it.

I used {IMG} {/IMG} (regular brackets NOT curly), the post simply showed up with:

IMAGE
IMAGE
IMAGE
IMAGE

....maybe I didn't wait long enough? Will try again....






we will see, LOL.

Fish

[Gotwind Ben]

Good to see some real world work there Fish,
This may not transalate so well, I mean this comment positively where actually doing is a little different (and takes a lot longer) than talking about it.

You may consider taking a look at Robs (Rfrink here) U.S. Vawt component supply page.
http://www.windgenkits.com/

Alternatevly, I believe a 48v bicycle hub motor would do a similar job with the wings/blades you have constructed ;) - Not proven yet, bit cheaper though..

Good luck, I look forward to a further update.

I've Just looked at your above image filenames, they need to have no spaces in them, that could have delayed things a bit, not sure - it works fine here.

Thanks Ben, I have looked @ Rob's kits and discussed modding it for my use, but we both felt it was "not quite right".

I have purchased pretty much the "last bits" (until there are more, lol) for my install. I am going to use a 4in piece of PVC as the "main column" with an internal piece of 2in PVC. The "wings" will be secured to the "column" by 1/2in copper tubing. The 1/2in copper tubing will be attached to the "main column" by 1/2 NPT directly into the PVC. This is likely the "weakest link". The "wing side" of the 1/2in copper tubing will again be 1/2 NPT into a 2inx2inx1/4in "L-Bar" attached to the wing. I really wanted to use 3/4in copper, but honestly feel like the 1/2in is sufficient, and I didn't have a 3/4in MPT tap. The Double PVC (4in & 2in) will connect to a 42in piece of 1in grade 8 fine thread, thread-all which will pass through a 1in wheel Hub. 30 inches of the thread-all will extend through the double PVC column, the rest will pass through the Hub and connect to the 5:1 speed reducer which will attach to the pump. The ultimate goal is a 2M tall wing set with 1M separation from the roof apex. The turbine will be mounted on a "pump house" that was built specifically to handle the wind turbine load. (Pictures to come). Hopefully in the next week or two I will be able to put the bit together and set them in the wind for a video (pre-installation).

I know most here want to go from idea to spinning in a day or two, but I have been planning this for over a year. I hope to wrap up this project sometime between July and October, but I should have it "spinning" in the next week or two :-)

Fish

This is just a "follow up" to help explain my above post. When I refer to a "center column" the idea is fundamentally different from the original design of the Lenz II. In the Lenz II their is an "external" support cage with a top and bottom bearing. The turbine spins on a stationary axle. My version needed to have a "live axle" with a stationary hub, so some fundamental changes had to be made. I spent a great deal of time deliberating how to achieve this. What is needed is a strong/rigid center column that prevents deflection and transmits the power to a shaft that extends through a bearing carrier and roof ridge to my gear reducer. I have drawn up dozens of scenarios, but in the end I am limited by cost and machining capabilities. What I would have really liked is a stationary 3in steel column ~20 feet tall with an internal top bearing and an external bottom bearing and a 1.5in "internal" shaft extending from the top all the way through the external 3in stationary shaft; but I simply do not have a lathe large enough to machine the external or internal shafts. I devised numerous schemes to over come this, but the BOM was simply not reasonable. I finally decided on using an "off the shelf" wheel hub as the main bearing carrier simply for cost reasons. Once this decision was finally settled upon, the primary concern became preventing deflection in the rotating column. Again, my first choice was steel, but machining and costs kept making finding an alternative very attractive. I finally settled on a rather complex, but fairly easy to achieve system of "off the shelf" PVC components to create what should be a very rigid center column. The column (as stated) will consist of a 4in outer layer and a 2in inner layer. By machining 3in & 4in PVC fittings to remove the "stops", I can create 3/4in thick PVC layers to be drilled and tapped for standard 1/2in pipe thread. The internal 2in PVC will allow a 1in steel shaft to be coupled by "compression" to the external 4in column. Wow, I really need to scan my drawings and post them, that would make all of these words make sense. I will stop trying to explain the column and let the drawings "speak" with some pictures in a later post.

I guess I have completely failed to make my above post "clearer", rather I have probably simply further muddied the water. That is a shame; I am really excited that I have finally devised a way to connect the wings to my pump that is economical and NOT labor/machine intensive. I am a bit concerned about the 1in roller bearings in the wheel hub, but I guess time will tell there.

Grrrr, I do hate it when I utterly fail to communicate my ideas into plain English. Pictures and drawings will help and will follow.

Fish

It isn't pumping water; It isn't Balanced; It isn't painted/water-proofed; The wings probably aren't at the right angle; It isn't mounted where it is going to be; It might not make it through the night as there is a big storm on the way; It is spinning :-) Here are a couple pictures.





If it makes it through the night I will take it down and make some adjustments. The wind is swirling around it right now; the house is blocking it, but during gusts it is doing a little less than 30RPM. I suspect (and the calculations suggest) the max RPM should be less than 90RPM in a sustained 30mph wind w/no load. The radius is just over 1M. The torque is A LOT. During a gust it is very difficult to stop rotation by grasping the 4in PVC main column. With 5:1 gear reduction the torque will be incredible!

I will post the column construction and other details if it survives:-) I must say so far I am impressed by the Lenz design.

Fish

[Gotwind Ben]

Looks like you have made a good start Fish.
Hope it survived through the night..

It did in fact survive. Actually, it is still up. It rained on and off all day, so I just left it alone. I will do the whole construction process in this post, so it will be a bit lengthy!

First the Ribs. I made a pattern rib, then rough cut another 14 (a few extras). The process went like this:

Pattern Being drawn on stock:


Rough Cutting Parts:


Attaching the rough part to the pattern:


The Finished Part over the Pattern:


I already posted the wings, so I will skip them here. The next step was shaft construction:

The "Inner Shaft" Is constructed from 1in Fine Thread Grade 8 Steel. A 4in x2in External PVC coupler and a 3in to 2in coupler with 2in PVC sandwiched between make the basic part.....a picture is worth 1000 words:

The finished inner shaft:


The various bits:

Top:






Bottom:


Bottom Nut Detail:


Assembled Bottom Detail:




Whole Column Assembled:


And you have seen the above pictures...

I am going to replace the 1/2in copper "arms" with 1/2in galvanized steel; turn the wings "around" so rotation is counter-clockwise; and 10,000 other things, but I just needed to see it spin :-)

Fish

thanks for the update fish,

those airfoils and shaft look rock solid! good call with the upgrade to 1/2 steel arms. that long moment must have an asymectrical torque component in gusty winds..i would not call you chicken if you decided to go with support arms to each rib of the airfoils.

have you considered extending the shaft a meter or so more and run a wide set of guys? just clearing the top of the wings.

great stuff! thanks for the look,

cheers, dave

hehe, 30+mph winds + gusts =

sweet dreams and flying machines in pieces on the ground

--James Taylor--

LMFAO

Oddly enough it was the solder joint on one of the copper tube fittings that "let go". Sadly I was @ work when it occurred. I am really torn on the direction to go. I really need to re-do almost every aspect of what I have built, I wanted a "proof of concept" and I did it on "the cheap"; now I want something that will last 10+ years w/o much maintenance. I was VERY impressed with the torque created by the 42+ inch radius; very UNIMPRESSED with my 10ft x 4in PVC column rigidity; absolutely discouraged by a single 1in bearing pair in a wheel hub to handle the deflection associate with a 10ft moment arm....in short, lots to think about. In the end, I have to design/build my VAWT with the understanding it WILL SEE 100+mph winds within 2 years, and it has to be able to handle 150mph winds if I truly expect 10 year survivability. With one wing damaged and my entire central column idea in the scrap heap; I am torn. I am thinking I am going to contact rfrink again and discuss using some of his parts. Using a pair of his wing kits and four of his "tri-star" rotor pieces I think I can achieve the "durability"/torque I am after in the wings, but the central column and bearings are still a major issue. Unfortunately his bearing design simply is not suitable for my application; I need a centrally rotating main column, not a "rigid column", and this complicates using his parts, but this is a complication that is going to persist in any design. I would love to have access to his CNC laser facility, but he has already explained to me that he has no desire to "customize" the parts, and I certainly understand. Two of his wing kits + four of his "tri-star" rotor pieces will run ~$500 + shipping. My ideas for a central column + mast are looking like they will run another $250+. The bearing carriers et al will be mostly labor if I stick with 1in bearings, but I simply do not think 1in bearings are going to prove durable enough, but larger bearings introduce a considerable amount of expense in both labor and materials....Did I mention I am very torn on which direction to go?

The one thing I am 100% certain about is that I absolutely am in love with a large, low RPM VAWT spinning on my landscape. I am very confident I can make such a VAWT provide most of my water needs, both for domestic use and irrigation. I estimate water output will be between one and three ounces per revolution (5 to 15 ounces per pump stroke) yielding about 40-50 gallons per hour in a 15mph afternoon thermal. My "dump load" will be irrigation, and the vagaries of the wind here should more than quench my lawn's thirst :-) BUT Solving the various problems associate with living in a hurricane zone are troublesome. Building the same VAWT for 50mph survivability would simplify things greatly, but 150mph winds are highly probable in any given 5 year period, and survivability is paramount.

SOOOO, back to theory for another few months. Proof of concept build phase is complete; predictably ending in catastrophic failure. I spent ~ $200 on this phase of the project (more if you count vested costs in materials I already had on hand), and I learned a lot. I do not view this as "failure", but rather an important step in the ultimate build process. I do hope others are gaining something from my process. I am right at 2 years into this project, and I have documented all of it in this forum (Thank You Ben). I could certainly NOT have gotten to where I am in a "quick build"; planning things out is very important to ultimately achieving a goal in Renewable Energy.

Something that surprised me was the total weight of the assembled turbine. Obviously the 42in x 1in steel shaft and the Hub are a bit heavy, but for some reason I did not expect the wings/column et al to be nearly as heavy as they are. The wings "feel light" by themselves, but when assembled, not so light! I would guess the assembled turbine is between 75lbs and 100lbs. Putting it up//taking it down is a chore. (Especially taking it down in a 30mph+ wind! The potential for serious injury was present and immanent). The turbine is also VERY unwieldy in the wind, the torque is amazing! The actual installation will be on the roof of my water shed, some 20ft in the air. I really need to spend some time thinking this step through....a crane comes to mind LOL, but I really don't want the potential damage a crane would do to the yard//septic system etc.

Like I said, lots to think about.

Fish