1 1/4 pipe tower for 4' dia ecm wind mill.

[bsafe]

Thank you for the previous answers that have been provided. I have a 4' diameter turbine mounted on one 10' section of 1 1/4 thick wall water pipe. I would like to go higher by adding perhaps one or two more 10' sections of pipe. I remember reading that threaded couplings are frowned upon but a search turns up nothing. Any guidence on using a threaded coupling? Is one coupling to many? I dont have access to a welder...yet. Thank you, bsafe

[wooferhound]

Here is a story about a 10 foot mill on a 1.5 inch short pipe, and it wasn't enough...

http://www.fieldlines.com/story/2008/6/20/04423/6376

[wooferhound]

Forgot to mention, He starts out saying it is 2 inch pipe, but at the end of the thread he says he measured it ant it was only 1.5 inch

[bsafe]

Has anyone flown a 4' diameter mill on a 20 foot mast made from two pipes? How did you join them?

[MattM]

There is pipe and then there is tubing.  Your pipe is measure by its internal clearance.  Your tubing is measured by its external displacement.  Generally the tubing is much better built than the pipe for the same advertised "size".

[hayfarmer]

  here is a pic of a 3 foot amtek top section is   18 feet  of 1.5  inch sch 40 metal pipe pivoting over a  10 foot section of 2 inch welded like the pic shows all pipe is welded
  
  with outer 2 inch sleeves  over the joints.  it tilts up like a WET NOODLE.... lots of deflection in pipe makes me sick just watching it.have  tums  handy.wish I took the advise

  freely offered here to use bigger pipe.  size does matter. and also DO NOT use thread couplers they are too weak cutting into metal,  once in air and guyed down, its fine link:


   http://fieldlines.com/board/index.php/topic,131705.msg860554.html#msg860554


    hayfarmer

[birdhouse]

bsafe-
if my memory serves correctly, the threaded ends of the pipe are 50% thinner than the pipe itself due to the thread cutting.  so by joining them with a coupler, you now have two threaded ends in very close proximity to each other.  this creates a very weak joint. 

call up a fencing company.  they sell 20 or 21 foot chunks of galvo pipe for pretty cheap.  maybe look for three inch, and you'll sleep a lot better!

if your ears are open, you'll find someone that can weld for you at some point. 

adam