I can relate to this. My 150 foot Rohn 45 was erected in 1999 by a team of
friends led by a veteran ham friend tower erector. I chose Phillystran 6700
pound strength using PLP Big Grip dead ends. As recommended, the Phillystran
is terminated about 15 feet above ground level to avoid damage from grass
fires. The last run to the elevated guy poles is 1/4 EHS. A LOOS tension
gauge was used on the EHS. The guys are attached at 35, 70, 110 and 150 feet.
On the top is a Force-12 C4-XL antenna rotated by a Yaesu 2800. While setting
up the rotor direction, we noticed a significant amount of twist when the
antenna was rotated. The veteran recommended a three point guy bracket to
limit the twist. I bought one from Norm's Fabrication. I hired a professional
tower climber to install this bracket at 140 feet.
Before the climber arrived, I inspected the tower and found it looked like a
snake when viewed from the tower base. I adjusted each set of guys so that the
tower is now straight. I used a plumb bob at 35 feet to adjust the lower set
of guys prior to setting the rest. I did not use the LOOS gauge, but adjusted
the turnbuckles using a Crescent wrench to approximate equal force. This
required a lot of walking to-from each guy post, and back to the base to view
straightness. This was several years ago. Before each climb, I check for
straightness. No adjustment has been necessary since the initial setting.
I have three more towers to erect, but not sure if and when this will happen.
I purchased these towers and about 10,000 feet of Phillystran from a ham that
had a superstation that was dismantled when he moved out-of-state. They are
all Rohn 55. They will be installed using experience gained from the present
tower.
73, Keith NM5G
-----Original Message-----
From: TowerTalk <towertalk-bounces@contesting.com> On Behalf Of Grant Saviers
Sent: Wednesday, November 25, 2020 9:29 PM
To: Tower Talk <TowerTalk@contesting.com>
Subject: Re: [TowerTalk] Guy tension gauge
The tensions equalize if the tower is sufficiently flexible. Then the tower
might be pulled out of column at that guy, which is a really great way to
induce a tower to fail. Tighten each guy to achieve equal tensions WITH the
tower in column.
Grant KZ1W
On 11/25/2020 16:39, Steve, NR4M wrote:
> Hello Wayne,
>
> What is the Loos gauge telling you?
> Those things were intended for the type of cable used on boat rigging. They
> probably do that just fine.
> The finer stranding of the boat cable deflects more easily than the EHS cable
> would, so I think all bets are off as far as accuracy goes.
> The best you can do with a Loos gauge, and it probably does it just fine, is
> show you if the EHS tension is equal.
> But, if I recall my physics correctly, -if- all guys at any given level are
> identical ( same distance to each guy anchor, etc) then the tension on any
> one will be the same as the other two.
> I have a nice, brand new tension dynamometer and I have been intending for
> several years on taking pieces of 3/16, 1/4, 5/16 and 3/8 inch EHS, putting
> them in series with each other and the dynamometer between BIG trees, and try
> and calibrate a large Loos gauge.
>
> Just everyone be careful.
>
> 73 de Steve, NR4M
>
> Sent from my iPhone
>
>> On Nov 25, 2020, at 7:03 PM, Wayne Kline <w3ea@hotmail.com> wrote:
>>
>> John,
>>
>> Having used Phillystran I had either 3/16 , ¼ or 5/16 EHS cable
>> terminated to the ground anchor/turnbuckle I use a LOOSE gauge
>> This is not as accurate as a dynamo meter. BUT IMO for amature applications
>> it fits the bill.
>> I have never used it on Phillystran directly on the steel tail ends ..
>>
>> Wayne ,W3EA
>> Sent from Mail<https://go.microsoft.com/fwlink/?LinkId=550986> for
>> Windows 10
>>
>> From: John Simmons<mailto:jasimmons@pinewooddata.com>
>> Sent: Wednesday, November 25, 2020 6:23 PM
>> To: Tower Talk<mailto:towertalk@contesting.com>
>> Subject: [TowerTalk] Guy tension gauge
>>
>> Are there gauges available for Phillystran?
>>
>> --
>> 73,
>> -de John NI0K
>> https://www.qrz.com/db/NI0K
>>
>>
>> _______________________________________________
>>
>>
>>
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