In a message dated 9/4/02 11:21:05 AM Pacific Daylight Time,
na9d@speakeasy.net writes:
> > Fifty-feet of 25G has 2 sets of guys; the maximum guywire strength at the
> > anchor before failure is 8,000 pounds. This is SIGNIFICANTLY more than
the
> > capacity of the screw-in anchors. Even if you used one screw-in per guy,
> > you'd still have a mismatch. I'll sure someone will mention screw-in
creep
> > due to wet soil conditions.
>
> Where did you get the 8000 pound number? The specs on 3/16" guy wire from
> Rohn are 3990 pound breaking strength. 1/4" guy wire has 6650 pound
> strength and 5/16 guy wire has 11,200 pounds strength.
>
> So while the screw in anchor is rated at 2500 pounds, that's a lot closer
to
> the breaking strength of the guy wire which is less than half of what you
> said. Or where you combining both sets of guys?
Yes. Unfortunately I'm not an engineer so had the exact situation a
little wrong but at least I erred on the conservative side of things.
>
> So now I have another question: How much tension does one tighten the guy
> wires to?
>
The recommended tension for guys is approximately 10% of their ultimate
breaking strength. In the case of 3/16" EHS the UBS is 3990 pounds so the
tension should be 400 pounds at 70 degrees F.
The easiest, cheapest, and most accurate way to measure guy wire tension
is with a Loos tensioner. You can get more info at <A
HREF="http://www.championradio.com";>www.championradio.com</A>.
Cheers,
Steve K7LXC
Champion Radio Products
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