Tower Question

Discussion in 'General Questions' started by joshua24br, Dec 29, 2010.

  1. joshua24br

    joshua24br WindyNation Engineer

    I have ordered Hugh Piggot's Wind turbine book but it has not arrived just yet. Maybe one of you who has the book can tell me if it will address my question on building a tower for my 500watt PMA.

    Question-When using schedule 40 steel pipe to build a tower, I understand it is best to mate the two pipes 3" to 2.5" at least 12". My question is how to make the connection (weld, bolt...) The weight of the generator is more than 50lbs so there will be some downward pressure. I understand the majority of the pressure on the tower will be laterial. My second question in the same general manner has to do with how to attach the two sets of guide wires to the pole. It is my understanding the lower guide wires should be at the point where the two size pipes meet.

    The Windy Nation 500watt generator will be going up in East Africa. I'm trying to engineer and plan for all of the steps before getting into the field. Thank you in Advance, Joshua
  2. murray2paddles

    murray2paddles WindyNation Engineer

    Pretty busy tonight Joshua, but will talk to you tomorrow and try to help out .
  3. murray2paddles

    murray2paddles WindyNation Engineer

    Ok let's start, 1st how high are you planning for your tower ?

    The Windy 500 is not really that heavy of a turbine so if you are not planning on going bigger on the same tower you would not need your tower pipe to be any bigger than 2 inch. ( if you plan to go bigger build with larger pipe right from the start)
    Connecting the pipes. Usually the pipe lengths are 22 ft if you are joining full lengths or shorter pipe to get the length you want, it can be same method. Welding method, if it is 2 pieces of the same size you should grind a bevelled edge on the ends to be joined on both so when the weld takes place there has been deep penetration in both pipes to make the joining bead/ weld.
    That weld is all you should need but sometimes to ensure your tower strength and protect your investment another method is used and to do this, before you make your joining weld of those same diameter pipes measure back from the end on both and place a mark aproximately 1 1/2 inches, at that measurement drill a few holes through your tower pipes, three on each pipe offset of each other at the same distance back from the end should be sufficient. Now take a smaller size pipe, for example 1 1/2 inch, cut a six inch piece and insert it into the first pipe half it's length. Depending on the schedule size of your pipe you might have a nice tight fit on the OD size of the short piece fitting into the ID of the tower, if so then we can move on to the next step, But if the fit is sloppy we take a metal cutting blade on an angle grinder and cut a seam down the full length of the insert pipe, then we heat it with a torch and open it up enough to create that tighter fit. You might not even need the use of a torch to pry it open, we just never tried it.
    So now back to having fit the short insert inside the tower pipe half it's length, the insert is 6 inch long, it is inserted 3 inch and you now have three open holes that you drilled in the tower pipe that you can weld through to the insert pipe joining it to the main tower. Then bring the next tower piece over the remaining 3 inch insert and do the same weld through the drilled holes. When done you can make your finished weld on the beveled joined ends of the two main tower pieces. Another welding method would be, instead of drilling those holes you can use a bigger welding rod, turn the voltage up and use that rod to burn through your tower pipe to reach the insert pipe. Just be careful you don't burn through everything.

    You had also asked about joining a 2 1/2 to a 3 in, you can use much the same method by drilling / burning through your 3 in pipe and after having slipped it over the 2 1/2 in pipe weld through your holes and then weld the end of your overlap end of pipe of the 3 Inch to the 2 1/2 inch pipe .
    Talk to you more on wire size a wire placement on your tower later. will wait to see what questions you might have on this first. I do have a thread on some of this on the forum. Unfortunately it is spread all over from answering questions, but you can look under one of the headings on raising / lowering a 32 ft tower, even that might help answer a few questions and also let us know if you were planning on a tilt tower.
    Anything that is not clear, just keep asking.

    Happy New Year
  4. joshua24br

    joshua24br WindyNation Engineer

    Thank you very much for your reply. Here are my thoughts and responces.

    This tower will be built in rual east Africa. It will be @40' tilt up. My plan is to use the equall of 3" schedule 40 steel pipe then reduce down to 2.5". I am brining a short piece of 1.5" from the USA due to the fact that I want to make sure the WN slip ring/yaw bushing fit correctly for the top of the tower.

    I am using a design from
    and also Hugh Piggott's book A Wind Turbine Recipe Book.

    My plan for the guy wires is 2 sets of four. Top set of 1/4" steel cable 36" down from the top of the tower (using 36" blades), the bottom of 3/16" cable at the connection point of the two pipes in the tower. Both using lugs that are welded to the tower.

    The guy wire anchors will be at least 20" from the tower base.
    We will make use of a Jin pole appox 1/3 the tower height

    If I may ask a few questions about wire size. What are your recommendations for wire size between the generator and the battery bank? The run will be around 80" (I know that is not ideal, but we have to make due with what we have). I was thinking of 10guage or maybe 8guage. The battery bank will be wired at 24volt. We will attach a 1000watt inverter. We plan to use 12guage wire for everything after the inverter. This is an off the grid system. I was thinking it might be better to run 10guage after the inverter due to some long runs over 150" to out buildings.

    Thank you for your time and reply,
  5. murray2paddles

    murray2paddles WindyNation Engineer

    Hi Joshua

    Your choice on tower construction is the same as in all my write ups. I can raise or lower using the worm gear winch in approx 4 min. by myself.

    When you are putting up The Windy 500 @ 40 ft, you could get away with only using 2 in pipe. BUT, if you have access to the larger pipe, by all means go for it because then you have the option of increasing your turbine size if you choose later.
    Wire size is always contraversal,, in my write ups you will see I am using # 12 on some Windy 500's and my wire run is over 100 ft. I get ome of the highest amp recordings so it does work. Again on the plan for the future, the bigger the wire no one will argue will be better. Planning for later expansion I would recommend # 8 audio wire, encased in poly tubing to protect it from the sun/ UV then you won't go wrong.
    # 12 is ok on the other side of the inverter for that distance but not knowing what your uses will be my first thoughts are that the 1000 inverter is fairly small.
    The inverter you plan to use will probably have more than one outlet and if you plan on using all of them I would digest asking one of our forum members if h has any suggestions on how to make the best wiring choices rather than having to run multiple parallel wires in rpthe same direction. His name is Larry Leamy.

    I have two 500's and a 750 so I was wondering what your wind conditions will be like.
    Good luck
  6. murray2paddles

    murray2paddles WindyNation Engineer

    Just have to add, on the wire after the inverter, like I said # 12 will work because I m using it myself but again if you have access to using # 10 , do it !
  7. joshua24br

    joshua24br WindyNation Engineer

    Thank you again. Good to bounch ideas off other to make sure I'm on the right track. Some times the learning curve is fun and other time a real headache.

    The location is at the bottom of a steep valley with sides of approx 700-800 feet and 3/4 of a mile wide at the top. I have not been able to make any actual recordings of wind speeds. I have only been to this location twice Feb 2010 and Oct 2010. Both times the wind was constant and steady around 15-20mph.

    You asked about the intended useage of the power. This project is at an orphange with 27 young girls. They currently have no power of any kind and no water. This is common for the area. We are mainly powering lights and are using 7watt compact fluorescent bulbs. There will be limited recepticles for lite usage items such as computer and printer, radio and TV. We have access to Esolar products that are made in Australia and sold in Kenya. We are not sure of the totaly amp hour battery bank as it will be determined at the time we purchase them based on supply and cost.

    We will be making a video of the install process and will post that link here some time in late Feb.
    Happy New Year,
  8. joshua24br

    joshua24br WindyNation Engineer

    A few more questions:
    I have been researching the turnbuckles as I am thinking about buying them here in the US and taking them with us. I have noticed that they are rated for different "maximum working loads". Can you give me any insite on this? Does 400lbs -500lbs rating sound about right, seems a little lite to me! 1/4 inch galvanized with 4" span? Same question for the cable clamps, large difference on the type of material used for these. They seem to be really cheap or really exspensive. Murry, where are you flying your three generators?
  9. dlmcbm

    dlmcbm WindyNation Engineer

    these are the turnbuckles I used ... ed-3551822
    it dont say on the site but they are rated at 1500 lbs. the cable I use is rated at about 1300 lbs.
    The clamps, galvanized or stainless steel should be fine. I would think that most any one from a reputable dealer would work. FYI there is a right and a wrong way to put the cable clamps on also. make sure they are the right way or they wont hold. Basically the U-bolt goes over the side of the cable that is cut and the saddle goes over the cable going from tower to ground.
  10. dlmcbm

    dlmcbm WindyNation Engineer

  11. joshua24br

    joshua24br WindyNation Engineer

    Thank you all for the help. I love the on line forums. I hope that after I get a tower up and some experience under my belt that I too can help someone along. Joshua
  12. mark99

    mark99 WindyNation Engineer

    I would go with a # 10 wire after the inverter due to the length of your runs. My runs are that long and I have #10 wire and it works well. Keep in mind that some cheaper volt meters will read lower due to the square wave on cheaper inverters. A true rms volt meter will give you a correct volt reading. This is something I have run into and just wanted to pass it on. Good Luck Mark
  13. murray2paddles

    murray2paddles WindyNation Engineer


    you had asked about turn buckles. mine are 1/4 thread and 8 inch length. Very easy to work with and adequate strength.
    I think the clamps have already been explained and I agree with that information. I do recommend the 3 clamps per joint.
    Usually the turnbuckles and clamps are available at a hardware store if you have one to shop at.

    Earlier you had questioned about wire. I know you have also said you will use 1/4 inch wire, that is more than good. I know the site you have read on towers and that they recommend the use of 1/4 inch but don't forget they are using it on 2 kw and plus turbines with 10 and 12 ft blades. If you want to save a bit of cash for your Windy 500 all you will need is 3/16 wire. The 3/16 is also adequate for the Windy 750

    I really do recommend purchasing a furling mount from Windy. They are not that expensive and the security they can provide in saving your turbine and storage from over volts is well worth the cost. One other thing i have learned is when you have a furling mount it enables you to lower your turbine in heavy winds if you need to do any work or changes.. As you start to lower the turbine and it is no longer standing straight gravity takes over and the mount will automatically furl for you and stop spinning.
    Everything is up to you, I know you will alwasy hear from others that to go big on everything, that is not wrong,,,, but I am telling you that you do not always have to because i am doing it and I get very good results.

    You asked where my towers are, they are in Manitoba Canada on the shores of Lake Winnipeg.

    I am interested in your project, tell me when you are putting up one turbine, is that all you will need or is that all your project can afford ?
    [attachment=0:5xdqu83x]8 inch.jpg[/attachment:5xdqu83x]

    Attached Files:

  14. joshua24br

    joshua24br WindyNation Engineer

    I did buy the complete kit with furler mount. I waited all summer while Windy was testing them. For now this one 500 is all we can afford. I didn't learn of the new 700 until after. I might have bought that one. Going from no power of any kind to lights will be a great jump. We'll see how it goes up.

    I have read a few threads requarding the size of the battery bank and the effects on the Windy 500. Can anyone make any suggestions or guidlines. Suggestions on where to read up on the issue. There is a small solar panel I was hoping to add into the system. Actually i had forgot about that until now. How do I tie that into the system. I bought the 24V preassembeled control panel. Is it even feasable or worth it?

    We are very limited in the resources we have available in East Africa. We will be purchasing batteries and inverter from E-Solar when we arrive. Here is a link with the product specs: ... Itemid=123

    I think someone asked when we will be putting this tower and generator up. We are leaving the US on Jan 20th for 5 weeks in Kenya. I am not the most mechanical guy but more of a carpenter. Here is the web site for our Missionary Organization, called Missionary Safaris.

    Again, Thank you for feilding all my questions, I realize I have gotten off the topic of Towers.
  15. murray2paddles

    murray2paddles WindyNation Engineer

    Hey Joshua, I don't think you are off topic.. now that you have answered my questions on plans vrs funding,,, I would like to offer you two more turbines with blades for your project.
    The turbines would not be as good as a Windy but they both may serve your purpose. They would be a Wind Blue low wind and a Presto low wind turbine. I would supply you with Windy Nation five blade rotors and full set of blades for both.
    I do not want to burden you with more than you can handle right now but think it over and if you are interested I can either ship them to you soon or hold them for you until you complete this first project.

    Donated, only if your group could cover shipping

  16. joshua24br

    joshua24br WindyNation Engineer

    Thank you for the gracious offer. If you could, hold that idea and let me work out the bugs on this first project. I feel like I am full of questions and am trying to search the forum before asking a new question. Some times the excitment of details doesn't lend me to be very patient. I like to be very detailed in my planning. I am already feeling a bit over whelmed with getting this generator up in the five weeks I have to be on site. There is no Home Depot of parts store down the street where we will be going. One missing part or wrong size part could set us back days. I do like the Macgyver'ness of it all.
  17. murray2paddles

    murray2paddles WindyNation Engineer

    Ok I will hold them for you incase you would like them in the future.

    No home depots, I really understand you, I must travel 500 km roundbtrip to my store
  18. windyguru

    windyguru WindyNation Expert


    E-mail us at

    We have extra parts which we can donate to you for free. The parts are functionally perfect but due to aesthetic blemishes like scratches, we cannot sell them. We have some blades, hubs and other stuff that we would be happy to donate which will make for good spare parts.

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