I'm curious, Steve, where 1/4" EHS is used in place of recommended and
spec'd 3/16" EHS, does one tension the 1/4" EHS to 400 lbs. as one would do
with 3/16" or to whatever tension 1/4" is rated for?
Looking from another aspect, is the 400 lbs. tension specified when using
3/16" EHS on a Rohn 25g based on the tower type/heighth where 3/16" EHS
conveniently has a stength of 4000 lbs and the 400 lbs tension is just right
for the tower? Or should the tension be 10% of whatever guy wire size
strength is being used...e.g., 670 lbs. based on 1/4" EHS strength of 6700
lbs.?
73
Dale, kg5u
>
> In a message dated 4/23/2007 9:03:02 A.M. Pacific Daylight
> Time, towertalk-request@contesting.com writes:
>
> > I am in the process of erecting a few towers at the new
> QTH and have
> > a guy
> wire size question. Two of the towers will be Rohn 45 @
> 100' and the third
> will be Rohn 25 @ 100'. They will all have multiple yagis
> at various heights on them, so not just a top mounted
> antenna. The Rohn book indicates that each tower should be
> guyed at three elevations and the bottom two guys should be
> 3/16" EHS.
>
> > QUESTION: I have LOTS of 1/4" EHS and guy grips. Is the 3/16"
> > mandatory
> to
> meet the specs (as in the 1/4" is too heavy) or - is the
> 3/16" simply suggested (as in the 1/4" is not necessary but
> acceptable)?
>
> While the LXC Prime Directive to "DO what the
> manufacturer says" still applies, what you're proposing is a
> little bit of over-engineering (which is not discouraged, BTW).
>
> The capacity of any tower is a function of its leg
> strength. By using bigger guys you'll be putting more
> compression on the legs but at the heights you mentioned,
> it's not a big deal. 45G will go to 300' and 25G will go to
> 200' so you're not overstressing anything.
>
> Cheers & GL!
> Steve K7LXC
> TOWER TECH -
> Professional tower services for hams
> Cell; 206-890-4188
>
>
>
>
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