>> > I'm getting ready to extend the height of a 30' Rohn 25 bracketed tower to
>> > about 70' and I would like to use raised guy stays ( I think that is what
>> > they are called ) to get the guy wires above head height.
>> The best material is I-beam (eye-beam, H-beam). It's much stronger than
>>round elevated guys.
>> Put 60% of the guy in the ground and 40% above the ground and you'll be
>>in good shape.
>I-beams are the way to go. But let's see here, guy wires above head height
>= say 6 feet. Therefore 40% of x = 6 feet. If I recall my algebra correctly
>x would = 15 feet. Which would equate to 9 feet in the ground? I think this
>is a bit much for any 70 foot tower. Put the i-beam in the ground 4 foot
>with rebar and Johnson studs with concrete and it will hold anything you
>want to put up. A 10 foot i-beam is plenty.
Don't scrimp on the concrete though. In average soil it takes much more
concrete than one might think to keep the post from slowly leaning over
when under constant tipover force of a few hundred pounds at 6'. 2 or 3
yards is NOT too much.