In a message dated 99-04-01 08:29:53 EST, k9zm@frontiernet.net writes:
> These messages on 4 point guying reminded me that I have wanted to ask about
> guy wires slowly wearing their way thru towers. It was mentioned to loop
> the guy wires around the tower leg at the proper height. (At least that is
> how I took it) With the flex in the tower will that wear thru the cable or
> tower. I have never seen damage from this so I can only assume that the
> galvanize coating acts as a lubricant?
I don't think the Rohn guy-attached-to-leg drawing has been in a Rohn
catalog in awhile so apparently it's not a factory recommended method anymore;
I couldn't find it in a 1985 catalog either. The drawing shows that the guy
goes over/through the diagonals as well as around the leg.
If the guys are properly tensioned, there is so little movement that it
is a non-issue.
The galvanizing is just a coating, not a lubricant.
>
> In my situation, I opted to use a pointy top section with a Hazer setup on
a
> Rohn 25G. I have a anti-twist bracket and bars at 28' and I put another
> set of guys at the top by simply looping the guy wire and dropping it over
> the point at 57'. At the time I was simply trying to clear the Hazer when
> it was cranked to the top. The upper pulley bracket has a much stronger
> mount on a pointy section and because of where the Hazer sits on the cross
> legs on Rohn 25G, I was able to mount the first antenna at a lower height
on
> the mast and still clear the tower. There is very little movement in the
> tower at 28'. With the Hazer acting as a lever and with a Telrex TB6EM
(26'
> boom & 85lbs), a Cushcraft 40m dipole and a 2m vert, cabling and a T2X,
> there is a lot of movement at the top. I was wondering about the guy
cables
> sawing their way thru that top section.
>
You've got a problem. Your top guys are not attached to the legs and
thus offer NO torque resistance. The tower's going to twist like crazy in the
wind. Is this a recommended method? NO. Is this fatal? Possibly. I would re-
think your installation to eliminate this problem.
Cheers, Steve K7LXC
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