Philly is quite expensive compared to wire, insulators and fittings.
Good if its in the budget.
I didn't quite understand the concern over the weight of guy wires. Take
my latest project as an example, since I have no data on your tower.
Mine is 150 ft of Rohn 55, rotating with three K0XG rings. Guys a little
over 1:1 with the top guy at 42 degs neglecting sag. Bottom guy 17 degs.
Top guy 5/16, the rest 1/4. Guy wire weight is perhaps 250 lbs. Rings
sum to 450 pounds. What I won't have, since the tower rotates, is the 3
inch mast and medium prop pitch I used on my Rohn 45 160 ft tower that
survived San Diego county Santa Ana winds for 16 years. About an even
trade for the rings. With a 50 ft 5L20M ant at 175 ft and lesser size
ants below it.
Then each guy is stressed to 5-10% of its strength. Each guy, therefore,
is under more stress than the entire weight of all guys. Rohn 55 is
rated to 400 feet in my 90MPH wind configuration, that is 4,000 lb of
tower plus guy stress and weight without anything on top.
My conclusion is wire guy weight is not exactly inconsequential, they do
weigh something, but is a minor effect in the overall tower scheme. One
solidly built climber weighs about the same.
I'd be far more concerned about calculations for what you intend to put
on it, how many guy levels are necessary to support that load in your
wind loading/icing conditions, what size guys to use, and of course, all
that vs the tower specs. It might be really beefy looking tower - but
they all have limits.
73 Art
On 9/21/2011 12:50 PM, Jay Kesterson K0GU wrote:
> On 9/21/2011 11:31 AM, 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@hetzel.org
> If you can afford it you can do it with Phillystran.
>
> http://www.phillystran.com/163.htm
>
> I'm not sure this has any relevance on anything but most people I
> know with tall tower often only have one set of guy anchors. So the
> lower guys are already at a much reduced angle.
>
> 73, Jay K0GU
> _______________________________________________
>
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--
Regards
Art
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