At 12:09 AM 8/10/98 -0400, Gregg Corsello wrote:
>
>check out the photos of Rohn 55G toppled at K8DX's QTH:
>
>http://www.qsl.net/k3gp
>
>73, de Gregg, K3QK
Gregg, I am not sure if you are implying that Rohn 55 is not strong
enough based on K8DX's experinece, but it appeared to me from the
photos on the K3GP site that the failure point may have been the
turnbuckles. It appeared that they might have been simple hardware
store formed turnbuckles, which are woefully inadequate.
If, in fact, they were formed turnbuckles rather than FORGED turnbuckles
they may fail with as little as 600-700 pounds of force on them. Not
much comfort when 1/4 inch EHS guy wire is rated at 6,700 pounds.
I dropped a note to K8DX a few weeks ago to better understand the
reason's for the tower collapse--other than just the fact that trees
fell onto the guy wires in the wind storm. I wanted to understand what
the weakest link might have been, but the note went unanswered.
Understandable under the circumstances--Scott was probably still
picking up the pieces.
In any case, Rohn 55, properly guyed, will handle most anything,
except for an 80M beam. If I was putting a large, heavy 40M beam
on it I would probably do a star guy for the top to better resist the
starting torque of the 40M. (But if I could find or afford 65 I would
certainly put it up and then load it up with everything I ever wanted to
put up. But 65 is in a different class than 55--it requires professional
level tools and expertise to install properly.)
73 John W0UN
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