[TowerTalk] Rohn 25

[Hank Lonberg]

Malcolm:

If you notice the sections get larger as you go downward from the top. The
tower sections get stronger and can handle more moment as you go downward.
Just like the moment diagram for a cantilever beam, which they are albeit
vertical. The maximum moment is at the bottom and reduces as you go towards
the top. Rohn 25,45,55,65 are constant in section size.

Regards
Lonberg Design Group, Ltd.

Hank Lonberg, P.E.,S.E. / KR7X
President

-----Original Message-----
From: towertalk-bounces at contesting.com
[mailto:towertalk-bounces at contesting.com] On Behalf Of Malcolm Ringel
Sent: Saturday, January 29, 2005 9:03 AM
To: Al Williams; towertalk
Subject: Re: [TowerTalk] Rohn 25

Al: Not an expert by any means, but, having had (and still have one) a 
couple of crank-up tilt-overs (and never a problem ...even though never 
cranked down for storms, etc) I think it has , at least in large part, to do

with weight distribution. The nesting aspect of the sections calls for 
largest at the base and smaller as you ascend...also, there is usually a 
several foot overlap at the section junctions, making for greater strength 
at those points. Finally, I believe that c-u/t-o towers usually have more 
concrete in their larger base cavities.
I await the sting of the arrows of those who actually can explain it....H I
73
Malcolm Ringel
ARS K3KZ
St. Michaels, MD
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----- Original Message ----- 
From: "Al Williams" <alwilliams at olywa.net>
To: "towertalk" <towertalk at contesting.com>
Sent: Saturday, January 29, 2005 11:54 AM
Subject: Re: [TowerTalk] Rohn 25


>
>
>> I had 70' of Rohn 45 up, unguyed, at one time, and it was scary.  I
> got it
>> guyed right away.  Rohn 25 would be scarier.  73 - Rich, KE3Q
>>
> What in the design and construction of crankup towers allows them to be
> free standing
> whereas the others requiring guying?   Intuitively, it would seem that
> just the opposite
> would be true;  or could be made true with a change small change in the
> design?
>
> k7puc
>
> _______________________________________________
>
> See: http://www.mscomputer.com  for "Self Supporting Towers", "Wireless 
> Weather Stations", and lot's more.  Call Toll Free, 1-800-333-9041 with 
> any questions and ask for Sherman, W2FLA.
>
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_______________________________________________

See: http://www.mscomputer.com  for "Self Supporting Towers", "Wireless
Weather Stations", and lot's more.  Call Toll Free, 1-800-333-9041 with any
questions and ask for Sherman, W2FLA.

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