Hello Roger - thank you for your post.
I was planning the same approach.
The use of torque arms (bars) does reduce tower twist, but will not eliminate
it.
Usage of a Star Guy assembly (which features 2 parallel cables per 120 degrees)
provides extreme anti-twist and tower stability.
A torque arm and Star Guy assembly encircles the entire tower, which dissipates
the stress in the same fashion.
With this in mind, stress on individual tower legs and the accompanying welds
is greatly reduced.
Use of thimbles protect the guy cable within these devices.
... a little of me ...
I am also a certified tower technician, with welding endorsements.
I have 3 years of collegiate engineering physics, 2 years of structural
architecture.
Electrical - yes, including grounding and terminations.
I am contracted out occasionally by 3 different companies, from new to repair.
As towers and related equipment age, finding a qualified welder (above grade
level) is few and far between.
Respectively Submitted,
James
ki5dq
--------------------------------------------
On Thu, 1/12/17, Roger (K8RI) on TT <K8RI-on-TowerTalk@tm.net> wrote:
Subject: Re: [TowerTalk] torque arms or not?
To: towertalk@contesting.com
Date: Thursday, January 12, 2017, 5:16 PM
Although it's a common practice with hams, Guys should be attached to a
bracket, not individual tower legs.
It's not normally a problem, but guy brackets like ROHN sells puts no strain
on
an individual tower leg. On a heavily loaded tower,(near its wind load
limit), when the guys are
attached to individual tower legs, in high winds, the tower leg on the
windward side takes the
strain. With a guy bracket encircles the tower with the guy strain taken by
the
bracket and converted to a downward force, putting far less strain on the
tower.
You don't see commercial towers with the guy wrapped around a leg.
73, Roger (K8RI)
On 1/11/2017 11:27 AM, Steve London wrote:
> K7LXC wrote:
>
> Correcto mundo. In the years before the TIA-222, ham wisdom was that
> the foot long or so torque arms were a necessary part of tower
> construction.
> Turns out that they really didn't do anything for tower torque but were
> useful only by taking some of the twist out of the movement while being
> climbed.
>
>
-----------------
>
>
In recent years, I have seen the suggestion that using the torque arms
> eliminates the possibility that the guy wires could "chew" their way
> through the tower bracing or legs. I could imagine this happening over
> a period of years as the twisting of the tower causes abrasion of the
> tower by the guy wire. I have never heard of this actually happening.
>
> 73,
> Steve, N2IC
>
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--
73
Roger (K8RI)
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