A few comments and a question.
Having about 2 miles of wire fencing at my ranch, I've learned that most
of the farm store "hi-tensile" wire is import junk. It stretches and
stretches. So my ranch hand goes far out of his way to buy US made
branded fencing wire that he knows. Caveat emptor. Also, using single
strand essentially unrated wire in a man rated application like a tower
guy seems a bit risky to me. The 1250# break strength seems a bit low
since a rule of thumb is Breaking load > 10x SWL. The single strand
galvanizing is likely electroplated instead of hot dipped, so corrosion
deterioration may be fast.
My question is: do tower professionals use the Klein Chicago Grips that
are specifically made to temporarily hold EHS? I have used them to
slack guys and re-attach them, etc. A come-along can do the temporary
holding, etc. This seems much simpler than other approaches.
Grant KZ1W
On 3/31/2011 11:18 AM, Donald Chester wrote:
> I would recommend approximately # 10 gauge solid galvanised "high tensile"
> fencing wire for temporary guys. It is inexpensive and available at about any
> agricultural supply outlet. It doesn't stretch, and has a rated breaking
> strength of something like 1250 lbs.
>
> Substitute a temporary guy wire for a permanent one only one guy wire at a
> time, and proceed to the next guy wire only after the previous permanent one
> has been fully repaired or replaced. It goes without saying to install and
> tension the temporary guy before disassembling the permanent one. I have a
> couple of extra turnbuckles on hand, and use one of those to tension the
> temporary. I pull the temporary as tight as I can by hand, and then attach to
> the turnbuckle, which is run out almost to maximum length. Then the
> turnbuckle is retracted until there is enough tension on the temporary to
> cause a perceptible drop in the tension on the main guy. Besides safety
> concerns, another reason to do only one guy wire at a time is that prior to
> doing the work you can make sure the old guys are properly tensioned, and
> then it is easy to adjust the tension on the new one by tightening it until
> the tower is perfectly aligned and straight and/or the sag is equal on all 3
> guys. Do this one guy at a time and you won't have to go through the entire
> process of measuring and adjusting tension of the entire set of cables at the
> guy point.
>
> High tensile fence wire is stiff and springy much like EHS stranded guy
> cable, but not hard to work with with the proper tools. I would suggest a
> couple of pairs of vice-grips for bending and cutting. Fasten with 1/8"
> u-bolt cable clamps, also available at the agricultural supplier for about
> 35¢ each, using 3 clamps to terminate each end. Be sure to wear gloves if you
> don't want to come away from the job looking like you just lost a fight with
> an alley cat. Make absolutely sure there is no kink in the wire before
> pulling on it. Applying even a slight amount of tension to a kinked wire
> will seriously weaken it at the point of the kink, even if the bend is
> straightened. If a kink is inadvertently pulled, replace the wire or cut it
> at the kink and install a strain insulator and properly clamp and terminate
> each of the loose ends.
>
> I wouldn't use this to permanently guy a tower, but I wouldn't go up to do
> tower work during a hurricane either. It should work perfectly to
> permanently guy a tubular mast up to 65' or so. I would use 3 clamps per
> termination to install strain insulators, because this wire is far too stiff
> to easily use the twist and wrap method.
>
> I also use this same wire as a messenger cable to support a 150' long
> above-ground run of RG-213, as well as the run of standard 7-conductor rotor
> cable I use to operate my remote controlled antenna tuning unit.
>
>
>
> Don k4kyv
>
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