On 4/2/2011 1:30 AM, John Crovelli wrote:
> Warning: USING ROPE FOR TEMPORARY TOWER GUYING CAN BE HAZARDOUS TO YOUR
> HEALTH. SUDDEN GUY SYSTEM FAILURES CAN CAUSE SERIOUS INJURY AND EVEN DEATH.
> WHEN WORKING ON TOWERS DO NOT TAKE SHORTCUTS. THINK TWICE BEFORE TAKING
> ANY ACTION THAT COULD PUT YOUR LIFE UNNECESSARILY IN HARMS WAY (CAPS used for
> emphasis).
>
> Hope I've gained your attention. This is a terribly serious subject.
> Comments posted on TT this week may have lead some less experienced or
> knowledgeable readers to believe using rope for guying is OK. Well, its not
> OK.....not at all OK in my opinion.
First, sorry you were hurt, but glad for a rapid recovery and I do agree
with most of what you say.
Like Gary your accident narrative raises some questions. What kind of
rope? You said it had been used many times. How old was the rope and
how much use had it had? You were in the process of raising something up
the tower, was it going straight up the side, with the rope coming down
the tower to a pulley at the base, or was there some side pull. How
many people were pulling on the rope to the gin pole?
Quality rope of sufficient strength that is inspected prior to use is
used in mounting climbing and for temporary guys safely on relatively
small towers.
As I'm never more than 35' from permanent guys and I never used them for
anything other than tower assembly or disassemble (and a guy
replacement) they are unlikely to have much of a load (other than
tension) on them.
Regardless of the type of material used for temporary guys and tower
work, the users/workers must be knowledgeable about what they are doing
and the risks involved. Although many hams treat climbing with a
cavalier attitude, it is dangerous. I feel far more comfortable on my
45G than I do on a 25G and I feel far more comfortable on MY 25G than I
do the typical 25G or ham tower. More than once I have recommended just
dumping the whole works over instead of trying to disassemble it as I
considered the tower in question to be unsafe for climbing. Dangerous
would be a better word than unsafe.
I prefer wire rope for temporary guys and I *personally* (this is not a
recommendation) do not like EHS as temporary guys. The reason is EHS is
heavy. Very heavy and weight plus height = potential energy. A properly
tensioned guy has a LOT of energy. IF they break or come loose due to a
poor connection they can be deadly. Tension, stretch, and catenary *all*
add to the potential for mayhem should the guy break or disconnect.
Yes I've been on a tower when a permanent steel guy broke. A tractor ran
into the guy anchor. Only the one guy broke and the anchor end almost
made it up to me. To say it was... well... exciting would be an
understatement. I had both arms and both legs wrapped around the 70'
level (give or take) of a small tower while trying to grab the harness
release and hollering at the top of the lungs to the tractor driver who
couldn't hear me anyway. Other than a LOT of shaking the tower stood.
Over the years I've seen 25G and TV type towers guyed with 1/4" and I
believe it was 5/16" EHS. They guying system on these towers overloaded
the towers before anything was installed. It only takes a few minutes
to calculate the additional vertical force put on a tower from the
weight and tension of each guy and oversize guys put tremendous load on
a tower. From past experience I've found it all too common. Of course
I've found many guy installations that were also insufficient, from a
size, and installation approach too. The typical wrong step and most
common is to just wrap the guy (what ever material) around the tower leg
instead of using guy brackets. The brackets transfer the load to the
entire tower while the typical approach may put most of the side load on
a single tower leg.
Were it not for the cross bracing the load from a single guy could be
sufficient to bend that leg which is another reason to make sure all
tower sections are straight. Small towers tend to take a set and
particularly so if the guys are not all properly tensioned. This is even
more of a problem when inexpensive TV or light duty towers are used.
Sorry I digressed a bit from temp guys.
73
Roger (K8RI)
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