[TowerTalk] More Rohn

[k7lxc at aol.com]

In a message dated 1/14/2010 10:37:56 A.M. Pacific Standard Time,  
towertalk-request at contesting.com writes:

>  Rohn says 25G is not self supportiing, at all, but I have in  my hand a
drawing of a Rohn "Self Supporting Base  Plate"!!

>  SO, keep 'em coming.  I'm sifting all the data  to decide what I want to 
do.
It's obvious that 25G is a strong tower that  can do way more than they say.
I'm not trying to cut corners and be unsafe,  but would like to know the 
real
structural responses in a real tower.   Maybe I should use some of my
considerable experience with strain  gages!


    You're asking engineering questions and you need  engineering 
calculations to answer them. Strain gauges will tell you at what  point something 
failed but I don't think that's the result you're after.  

>  What I really want, of course is a spreadsheet or drawing  giving 
windload,
bending, and shear at all points on a 70' stick of  25G!  Who knows, I may
have to buckle down and do it myself.
 
    Umm, good idea. More engineering data. And of  course if you ask an 
engineer a specific question, many times their response  is "It depends."
 
    Rohn published a pamphlet called "Manufacturer's  Technical Information 
For Bracketed or Self Supporting Towers" where they have  provided that 
information. I have it in a Word file and if you're interested,  I'll email it 
to you. It's not the whole pamphlet but the pertinent 25G &  45G sections. 

Cheers,
Steve    K7LXC
TOWER TECH 
and 
www.championradio.com