>
> A ham I know just moved, and left to towers. There is nothing really
> valuable on top; but they need to come down. They have been up for about
> 30 years.
I used to do a lot of smaller tower work and in my younger years even
installed TV antennas as a sideline, but we finally got down to the point
where about the only jobs were high pitched roofs on top of 3 story homes.
I don't mind climbing tower to this day, but I do not like high pitched
roofs.
>
> They are welded, extruded (I believe) tubular steel construction. Each
> section is 10 feet, three legged, with a triangular cross section welded
> in. These cross sections are every 18 inches or so. Four sections are
These sound like the old American Steel TV towers but the braces are 2 feet
apart and not 18 inches which makes them a bear to climb.
> bolted together (3 bolts), for a 40 foot (plus 10 foot mast) height (50 ft
Normally the bolt count is per leg, but "I think" you mean these are one
bolt tower legs with a total of three bolts per section which are not really
considered "climbable" towers.
A.S. had two common towers. One was a two bolt and the other a one bolt.
There are a *lot* of two bolt towers here in the states holding up
tri-banders from 30 to 60 feet. Probably over half of which use a "dirt
base" (ROHN used to make a dirt base as well...maybe still do?)
These are not particularly solid towers.
> total). They are bracketed against the house( about the 10 ft level). The
> base, for both, is the bottom section set in a small amount of
> buried concrete(about 2 feet deep).
>
> This type of TV antenna tower (about 30 to 50 feet height) is quite common
> in the Toronto Ontario area. I don't know who manufactured them; but there
> are a lot of them. They were commonly known as bracketed towers. Sometimes
> they are on top of apartment buildings where they have guy wires.
>
Most of those guy wires are probably the equivelant of Radio Shack 1/8" soft
steel guy line.
These are not really systems that should be climbed, but I have seen people
go up towers I'd not go near.
> I have climbed this type of tower; but as I get older, and they get older,
> I get more leery of doing it. The ones I am considering, appear quite
> solid to about 1/3 the way up, but are pitted and rusted further up.
It's usually the other way around unless they are near a chimney. Exhaust
gases from fireplaces, and furnaces, be they wood, coal, or nautral gas
fired are extremely corosive.
I'd be extremely leary about climing anything with rust and pitting.
No way would I climb more than 20 feet above the house bracket on a new
tower and back then I only weighed 150#. That was a lot of Turkey dinners
ago.
>
> Does anyone have any suggestions about how to take them down?
>
First: Common sense. Never, ever, go beyond your comfort factor.
The most difficult climbing I ever did was getting a guy down off a tower
who went past his comfort factor and froze. This was on a relatively heavy
tower compared to ham installations and he was only about 60 feet up. I had
to work him down, one hand and one foot at a time.
These are small and relatively light installations, but they are going to be
a bit much for one man.
*This is not a how to set of instructions, but rather what I have done with
some installations*
As I said, use common sense and proceede at your own risk. Speaking of
risk, there is always risk associated with tower climbing, taking down
towers and much moreso when the condition of the tower is in question..
Safety suggestion: Find some one locally who is familiar with doing this
and the how to do it safely even if they do nothing more than offer
suggestions and observe.
First: Develop a plan. Get your people and equipment together and decide
ahead of time who is going to do what and when. If something goes wrong
everyone should know which way to jump OR RUN. Know where all obsticals are
located. Backing away from a falling tower is not the time to discover you
have just tripped over a flower pot. Stick with smaller towers such as 40
feet. 50 feet with small antennas takes a crew of about 5 strong men who
know what they are doing.
With bracketed towers I have hooked a rope onto the tower around 2/3 to 3/4
of the way up. You can use a pole to put the rope up there with a weight on
the end of the rope so it'll drop down where you can reach.
One method I've used has been to run the rope over the roof to the other
side of the house.
Take the bolts out of the bottom (they should be just above the ground
level. If not, the judicious use of a hack saw may be required) Get two
men, or what ever the required number to hold the base, disconnect the
bracket, and with how ever many men needed on the rope over tht top of the
house, let the tower tip out away from the side of the house. It may take
one or two men to hold the base down and another couple to walk the tower
down.
Hinged bases make this far easier.
(CAUTION) Make certain the tower, antennas, guylines, or any other part will
be well away from power lines and none of the above are capable of
contacting such even if it gets away from the crew.
> I can never remember seeing anyone else climbing one, or even putting one
There's probably a good reason for that.<:-))
> up. Does anyone recall how these things were erected? Some of them have a
Quite often they were put together on the ground with the tower propped up
on a step ladder. Then a team of people would hold down the base while
"walking" the tower up into place and fastening it to the bracket clamp
which was "usually" already in place.
> 30 pound (or more) approx. 2.5 inch (it varies) 12 foot mast, with stacked
> yagis and rotors on top. I can't imagine the average 230 pound TV guy
> swaying around on top (40 feet plus), and hauling up and installing all
> that gear.
That's OK as the average 230# TV guy can't imagine it either.
Good Luck and stay safe.
Roger Halstead (K8RI and ARRL 40 year Life Member)
N833R - World's oldest Debonair CD-2
www.rogerhalstead.com
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