Marty, I welcome your true life experience. So here is one of the many
problems with this reflector ... you get beat up posting your real life
experience which trumps any theory any day. A lot of these
misinformation specialists believe that you have to over engineer
everything. If Steve posts this, I expect to get a lot of flak for
speaking frankly. BTW, flak is eliminated with the delete key. More
people get killed or injured on the highways every day and we still
continue to drive. Sheesh, get realistic and put everything in proper
perspective. This reminds me of the people in the great global warming
swindle.
Doug
I'll run the race and I will never be the same again.
-----Original Message-----
I must be a heretic on tower building. If I were an engineer, I'd
probably
still be designing my first tower. I can see stress tensioning the guys
on
a 600' commercial tower, anyone can, but on 50' or 60' of Rohn 25 I
really
do not see the need to get wrapped around an axle over it. In the older
catalogs, 40' was self supporting. It wasn't until the lawyers got
involved
that it had to be guyed at 20 through 40 feet.
I have 8 towers up at this time from 20 to 80 feet. I guy my towers when
they are at 50' and above. To be honest, I have lost 2 towers. When
Hurricane
Ike went directly over my place a tree snapped and fell across the guy
wires to those 2 towers and brought them down. They might still be
standing
without the guys...never know. Also I only put one beam on a tower,
mainly
to keep a clean pattern. If one's intent is to stack 4 el 40m beams,
guy
away by all means.
My thoughts, as wrong as they may be, are that the guys on a 60' tower
only
need to be tight enough to keep the tower vertical. I've never pulled a
guy wire more than hand tight on a turnbuckle. What would be the need
to
apply much more vertical and horizontal stress on a tower? If the
tower flexes
one inch in a strong wind the guy wire on the windward side will
tighten
and apply the necessary force to stop the tower movement. The middle
guy
wires only need to be snug enough to keep the center sections of the
tower
from doing the hula.
Just my observations on tower guying after 3 hurricanes.
Marty Haley AB5GU
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com] On Behalf Of k7lxc@aol.com
Sent: January 16, 2010 11:09 AM
To: towertalk@contesting.com; brahmangou@aol.com
Subject: Re: [TowerTalk] Guying a tower....Heresy to follow..... True
statement!
In a message dated 1/16/2010 4:23:25 A.M. Pacific Standard Time,
towertalk-request@contesting.com writes:
> I must be a heretic on tower building. If I were an engineer, I'd
probably
still be designing my first tower.
If you were an engineer, you'd be observing Laws of science as well as
engineering and legal codes - not "back of the envelope" estimates.
> I can see stress tensioning the guys on
a 600' commercial tower, anyone can, but on 50' or 60' of Rohn 25 I
really
do not see the need to get wrapped around an axle over it. In the
older
catalogs, 40' was self supporting.
I think this was an old wive's tale (which I have in the past
repeated
myself). I've never seen that statement in any Rohn literature so I
don't
know where it came from ("I put it up and it didn't fall over"?).
OTOH Rohn towers are well known to endure amateur radio overloading
conditions on a regular basis without failure.
> It wasn't until the lawyers got involved that it had to be guyed at
20
through 40 feet.
While it's true that tower manufacturers are Insurance-driven
enterprises, the industry wide adoption of the original EIA-222 Tower
Standard made
manufacturers re-calculate their towers in light of these new standards
and publish new specifications.
> My thoughts, as wrong as they may be, are that the guys on a 60'
tower
only
need to be tight enough to keep the tower vertical.
So I expect your guys to be way under-guyed which has the potential to
introduce wind-induced guy wire slamming as the wind gusts and the
tower is
forcibly pushed to the end of the guy travel.
> I've never pulled a
guy wire more than hand tight on a turnbuckle. What would be the need
to
apply much more vertical and horizontal stress on a tower? If the
tower
flexes
one inch in a strong wind the guy wire on the windward side will
tighten
and apply the necessary force to stop the tower movement. The middle
guy
wires only need to be snug enough to keep the center sections of the
tower
from doing the hula.
Major violations of the LXC Prime Directive to "DO what the
manufacturer
says" aside, some of your advice is potentially dangerous and contrary
to
industry and manufacturer's specs. I'd say you've been lucky but then
every
time you speed you don't get a speeding ticket, do you?
Cheers,
Steve K7LXC
TOWER TECH -
Professional tower services for hams
Author of UP THE TOWER - the first tower book ever written
_www.championradio.com_ (http://www.championradio.com)
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