[TowerTalk] Maximum Guy Radius

[Steve Maki]

If you engineered this tower for large loads you'd probably end up with 
1/2"-5/8" guy wires. I have 190' of Rohn 80 (44" face) engineered for 
four cell carriers, (48) 1-5/8" feedlines, and stacked 40 meter beams. 
It's guyed at 80' and 160' with star mounts and double guys. It was 
spec'd for 9/16" EHS but I elected to use 35,000 lb Philly.

-Steve K8LX

On 9/21/2011 1:31 PM, Dorn Hetzel wrote:

> This tower is 180 ft in nine 20 foot sections of 46" face angle iron. 1400
> lbs a section, 12600 lbs total.
>
> I was sort of assuming I would have to use something on the order of 3/8 EHS
> for this.  Do you
> think this is something I could do with phillystran ?
>
> Regards,
>
> Dorn
> KB4EQ at hetzel.org
>
> On Wed, Sep 21, 2011 at 12:36 PM, Mark Robinson<markrob at mindspring.com>wrote:
>
>> If you use phillystran then there is a lot less weight involved in the guy
>> assemblies.
>>
>>
>> Mark N1UK
>>
>>
>> ----- Original Message -----
>> From: "David Robbins"<k1ttt at verizon.net>
>> To:<towertalk at contesting.com>
>>   Sent: Wednesday, 21 September, 2011 10:03 AM
>> Subject: Re: [TowerTalk] Maximum Guy Radius
>>
>>
>>>
>>> the answer is a definate maybe... with a caveat to 'do what the
>>> manufacturer says'.
>>>
>>> The problem is that as you move the guy point farther out you increase
>> the
>>> length of the guys which also increases their weight, and the amount of
>>> sag for a given tension, which may actually increase the movement of the
>>> tower.  the manufacturer has probably done that tradeoff study already
>> and
>>> decided that 80% was a good compromise between forces, length, weight,
>>> wind, cost, etc, etc, etc.
>>>
>>>
>>> Sep 21, 2011 09:33:55 AM, kb4eq at hetzel.org wrote:
>>>
>>> If I have a tower of a specific fixed height that I will be erecting,
>>> and I have plenty of room to do so, I would estimate that I should
>>> gain *some* additional strength against wind-load by moving the
>>> guy radius from 80% of height to 100% of height, since this will
>>> move the guy angle closer to horizontal and reduce the down
>>> force on the tower and increase the horizontal back-force for
>>> a given guy tension and a given stretch in a guy due to motion
>>> of the tower.
>>>
>>> Can anyone comment from either a practical experience or
>>> engineering point of view whether this estimate is sound?
>>>
>>> 73,
>>>
>>> Dorn Hetzel
>>> KB4EQ
>>> kb4eq at hetzel.org