I guess you are saying that the base will rotate before the tower breaks. I
don't think that much torque makes it to the base on a tall tower.
Certainly the pier pin base will not prevent your tower from moving at the
top. I never saw any movement at the base of my 160' Rohn 65G tower loaded
with large antennas, however the tower definitely twisted at the top before
I added a 6 way star guy.
KK9A
----- Original Message -----
From: "jeremy-ca" <km1h@jeremy.mv.com>
To: <john@kk9a.com>; <TOWERTALK@contesting.com>
Sent: Saturday, July 14, 2007 10:33 AM
Subject: Re: [TowerTalk] new tower
The tower will still move but it is not twisting as in winding up to a point
of possible fracture. The commercial site over on the next hill had 140' of
45G with the base buried in concrete and a bunch of sticks on it. After
about 15 years the bottom section fractured. The tower didnt collapse but
they replaced it with 55G on the same pad but drilled it for a pin.
We are both in a very exposed location with negative horizons and once above
the tree line the wind is almost always fairly strong even when it is dead
calm on the ground.
Carl
KM1H
----- Original Message -----
From: <john@kk9a.com>
To: <TOWERTALK@contesting.com>
Cc: <km1h@jeremy.mv.com>
Sent: Friday, July 13, 2007 10:57 PM
Subject: Re: [TowerTalk] new tower
>I agree that the pier pin lets the guys do the work and it is the best base
> for large tower. I don't think the pier pin base will do anything to
> minimize tower twisting. The best way to stop the twisting is to use a
> star
> guy bracket.
>
> John KK9A
>
>
>
> To: "Mark Robinson" <markrob@mindspring.com>,"Paul Hemby"
> <phemby@hotmail.com>, <towertalk@contesting.com>
> Subject: Re: [TowerTalk] new tower
> From: "jeremy-ca" <km1h@jeremy.mv.com>
> Date: Fri, 13 Jul 2007 21:34:21 -0400
> List-post: <mailto:towertalk@contesting.com>
>
> It minimizes the tower twisting forces especially at the base. Recommended
> by Rohn. Especially advantageous with a tall tower with a big load; lets
> the
> guys do the work. Ive been on the top of my tower with a strong wind
> blowing
> and with the 1/4" EHS it barely moves.
>
> Carl
> KM1H
>
>
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