More Tower Materials

[Ronnn]

I have a choice of using 3.5 schd 40 nestled in the four inch section,  or all four inch. [ a 34 and a 37 foot section ]  I'm not a welder and am convinced it would be a stronger joint to nestle the 3.5 piece a couple of feet into  the four inch section. The space between i.d. and o.d. being taken up by strapping welded to the 3.5 piece then all other appropriate welding measures taken. This would make the tower a little lighter and a little more flexible in the top section. Need some help with the pros and cons please. Also there is some 4" that is bent a little that I might use as the gin pole section. I had a welder that I trust tell me that two four inch sections properly welded is as strong as a single section of the same length. Which is best. I'm pretty sure I remember reading here that 3 and 3.5 inch #40 is plenty strong for a tower. What is the best way to go?

Ron

[fabricator]

What size turbine and how tall will the tower be?

[Ronnn]

It will be a 10 footer from the dans' book. It will probably be close to 60 feet depending on if the sections are nestled or butt welded.

Ron

[fabricator]

I would do the nesting thing, it is a very strong joint.

[halfcrazy]

you could also use a short piece of 3.5 inch to connect the 2 4 inch pipes say 12-16 inches into each pipe.

[Ronnn]

Good point. I'll be sure to do that if I go the 4 inch route all the way. Still looking for more opinions about easier rasing and lowering tho I don't know if it's even a factor if you do it with a truck in low range.

Ron

[freejuice]

Hi Ronn,

 I'm also doing the 4inch @ 60 feet...I have three sections. At each section I have a piece of 3.5 inch sch 40 pipe as a sleeve in the 4 inch, going into each section about 16 inches. Since the pipe has a bit of clearence between the two diameters ( .080 of an inch) I decided to lift a section by hand and I was surprised how much this allowed it to bend at the joint.

So I decided to beef things up a bit:

So I borrowed one of Hugh Piggot's ideas from his book and welded braces to the outside of the pipe too! So I  took some 1/2 x 3-1/2 x 15 inch long plate and welded the 1/2 inch edge to the outside of the pipe at the joints....each section of the pipe had the plate overlaying about 7-1/2 inches which was spaced at 90 degrees around the pipe.....only time will tell, hopefully I can raise it next weekend.

 If everyting goes well I will post an update!

 

[Ronnn]

Take pictures please of your guy attachments and your joint areas. That would be a huge help. It may be a while before I raise a tower. I have to figure out how to get those two sections up here. I was advised to weld strap materail to the 3.5 inch pipe to take the play out of the joint. But just now reading the .080 in your post I'm wondering about the wisdom of that. There has to be some play just to get the joints together. My tower sections are 34 and 37 feet long. They will be very heavy to move around much. How did you center the smaller pipe inside the 4" or did you? Re-examining the .080 again, I'm holding a micrometer and guestimating, it looks like something over a sixteenth of an inch. That is a fair amount of play when you double it. Or was .080 the the sum of the slop?   But some sort of thin strap material might not be a bad idea. Not being a welder it's tough to make decisions like these. I will be hiring a real welder when it's time to put it together. The maybe I can do the next one my self.

Thanks for the help.

Ron

[halfcrazy]

My tower is 84ft of 3 inch sched 40 with a 10ft turbine. I raise it with my 4 wheel drive single line pull and she does not even work mater fact we have done it with my dads standard and it basically idles.

[freejuice]

Ron,

 You can see some of the attachment if you click on my files. I actally have the guy attachments just slitly below the connetion points. However If I had known how Hug Piggot commonly made his connetions Iw loud have simply used one of the out side guy pipe braces I described above.

 Yes the total clearance was bout .080 which is over 1/16 of an inch, but under 3/32 and thats total clearance not per side ( sum of the slop)....click on my files you can see a pice of the 3.5 pipe shoved into the 4 inch.

 How I connected them?

 At first I was going to simply cross bot them on each tower section with 5/8 thru bolt...well since dicovering this "new way" to couple the sections together I simply used the welder to fill in the 5/8 bolt holes I had drilled, as anchoring tabs for the 3.5 to 4.0 sections.

 I will try to get you some photos here soon....

 all the best

 Gavin

 

[freejuice]

(blank)

[Ronnn]

Hi I remember looking at some of those pics before. I don't think there were that many the first time I looked. #51 has a circular weld in it. A welder friend mentioned something like that for tying two sections together with out going all the way around the pipe. That thing should stay up there till you decide to lower it. It looks very substantial. I like the way you did your base too. What size pipe does the four inch drop into? Is it always just a half inch larger to accomodate this? Would 4.5 if that's what it is,  be a fairly common pipe size? I'm pretty new to all this metal stuff. Thanks for taking the time to help.

Ron

[97fishmt]

Hi,

I slipped a 3'piece inside the first section and welded around the joint

and slipped a 3'section over the next section, slipped it up about 6-7'

and put the two sections together and then dropped the outer 3'piece

down over the joint like the inner one and trough bolted just the upper

section so not to weaken it much more.  Inside and outside support for my

gin pole.  Verry stong.  I used a cut off of the outer piece for a sleeve

at tower top for the guy wires also.  Welded on and then half pieces verticly

welded on.

[freejuice]

Hi Ron,

Yes the circular welds were a 5/8 hole I drilled completely through and welded it on each side to the 3-1/2 pipe.

  On the tower base, the 4 inch pipe drops over a piece of 3-1/2 inch pipe....I have yet to weld all of this into position. There will also be a brace added between the tower and the gin pole, actually the upright piece in the photos is the gin pole in the raised position.

Generally a 1/2inch size larger on Schedule 40 pipe should be a "slip fit" on the next size...you can find the actual ID/OD sizes of various pipe sizes on the internet. Keep in mind that steel pipe and steel tubings are two completely different beasts in regards to how the dimensions are listed. If not mistaken steel tubing measures from the OD while the various pipe sizes measure from the ID.

 The base is a piece of 3 inch x 9 inch wide solid bar stock The pipe that slips over it, supporting the gin pole and tower is a piece of sch 80 4inch pipe.

 as to your other question I dont think 4.5 inch size pipe is very common...its out there but you would probably have to order it...ouch

I still have some more welding to do...a few things in those photos are not completely finished.

 all the best,

 Gavin

[Ronnn]

Well keep up the good work. The #80 in the base seems like a good idea, as is the gusset between two pieces. I will probably run some guy wire between them too. I've seen this on a tower or two shown on this list. Every time I pick up a shovel of dirt lately I think of a sixty foot length of #40 with a hundred pounds at the other end.

How are you doing your anchors? Do you know anyone who has sucessfully used those cork screw things?

Ron

[Ronnn]

halfcrazy thanks for the encouragement. I see you are the  guy who is beta testing the Mcontrollersidnight controllers. I am hoping to get one of those when they come out. Sometime I'd love to hear about any changes in the stator to accommodate that controller. I called and talked to Robin one day and said someone from the list was testing for them. He mentioned some pretty spectacular power increases have been seen with their boxes. When I saw the picture on the site I thought DARTH CONTROLLER! People are going to want them in the living room just to look at them. I'm a sucker for Deco stuff.

Ron

[freejuice]

Ron,

 The anchors have about 1200lbs of concrete at each point. I hope this will be enough in this hard clay soil! There will be three guys for each anchor point.

 If you are looking at anchor options Check out Volvo farmer he used those monster sized arrowhead anchors and they apper to be rated up there! He appears to be having good luck out of them on his 40ft tower.

 All the best,

 Gavin

[hayfarmer]

Image0055_tower_pivot.jpg

have a question on the tower pivot above,am using 3.5 inch pipe for tower base and 3.5 inch for pivot pipe on a 3 inch pipe,Should I weld on stub pipes on to pivot like 3 inch ,then slip on the tower over stubs and weld onto stubs or weld the tower base to the pivot pipe? thanks.

[hayfarmer]

here's the link to pivot

http://www.fieldlines.com/images/scimages/16067/Image0055_tower_pivot.jpg

[TomW]