Geoff,
My unprofessional opinion is that it is not a big deal. Most things are
designed to flex. 5 degrees seems ok.....about what mine does (110' 45G
w/34XA at 117'). Even if you install face guys (vs standard point of
triangle guys) the flex will show up farther down the tower....unless of
course the attachment point is at the rotor plate level.....then the twist
will be applied to the guys and stop there.
73 Gary K7FR
At 10:55 AM 8/8/96 -0400, you wrote:
>Looking for advice on design and sources for
>guy attachments that will control tower
>twisting.
>
>The installation here is 140 feet of Rohn 45 with
>a 40-2CD at 150 feet and a 48-foot boom 20
>monobander at 139 feet. (These are the tops of
>two-stacks that have bottoms at 70 and 60
>feet.)
>
>Mast/rotor arrangement at the top is very solid
>(2.5 inch high strength alloy and a prop pitch), but
>the whole tower turns at the top about 5 degrees or
>so when the wind blows or when the rotor starts
>and stops. I have a massive rubber shaft-coupler
>between the rotor and the mast that helps absorb
>shock-torque, but the top couple of sections
>turn nonetheless.
>
>Should I be worried? I am considering going
>to a dual-guy arrangement for the top set of
>guys, with the big torque-controlling ears at
>the top (not sure of the correct terminology.)
>
>Anyone know if these attachment brackets are Rohn
>stock, and the best way to calculate how much torque
>they will assest?
>
> Thanks and 73,
>
> - Geoff, W0CG, Suffield, Ohio
>
>
>
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