Hi Pat,
Comments below:
Pat Barthelow wrote:
> Hello Folks,
>
> I often wondered why wooden poles are not more frequently considered for ham
> antenna supports. We have them in abundance, left over from the military at
> N6IJ.
That's good reason to use them. You HAVE them. The rest of us don't.
> A navy manual for analysis, treatment, and inspection of power poles
> shows them to be far stronger than I would have ever guessed. Many
> (unguyed) 65 footers can take in excess of 1900 lbs (Lemme... double check
> the book on that) horizontal load at the top of a pole set in the ground
> with a 1.5 safety factor, assuming the particular earth that the pole is set
> in, can take the forces involved. (This is a load to actual failure
> (breaking) of the pole)
According to an early Rohn catalog that I have, guyed Rohn 25 is good for about
18,000 pounds vertical load on the bottom section so 1,900 pounds does not sound
like a high number to me . . .
> I guessed logically, it must be a price issue, but recently found a
> definitive website of what seems to be the big daddy of pole makers. They
> have lots of useful info, and an interactive session to develop a quote for
> a pole, delivered to your specification.
>
> Their site: http://www.ldm.com
>
> I, just for jollies, asked for a very heavy duty (read...thick, H1 Class,
> 67" circumference, 6'from base) pressure preservative treated, 120' pole,
> delivered to Monterey, to see what we were looking at, price wise.
> McFarland quoted about $7K delivered. (Delivered, means on the flatbed, or
> on the ground, horizontal at the radio site) The McFarland site says that
> stick, would weigh abt 9,800 lbs. I guess, it might be another $500 to
> $1000 to set vertical, and put on pole steps.. Approx $3500 of that was
> transporation from Oregon. (Wow..think of the logistics of transporting a
> 120 footer.) My guess would be that, while not cheap, how does that
> compare with design and construction of a very heavy duty 120 foot guyed
> tower?
Wow! There are lots of issues here. I have personally owned 3 wood poles in my
day and one of them was a 110 foot treated monster that I got used for $150. I
prefer towers. The reason I used the 110 footer was that my city lot was only
63 feet wide and there was no room to guy a tall tower . . .
1. You have to hire virtually all of the work done to set up or even transport
a huge pole. Your ham buddies just can't handle 100 foot multi-ton poles like
they can tower sections.
2. Poles are a LOT more diffiucult to work on. Ever try climbing a 24"
diameter pole with steps on it? It is a WIDE stretch and your climbing belt
gets hung on every step. It tapers as it goes up and you have to readjust your
lanyard as you climb. Poles have nasty slivvers, too. There are very few
places to tie ropes or hang your tool bucket on a pole.
3. If you move, how do you take it with you? I was lucky because I actually
found a buyer for my giant pole. I sold it back to the same guy who sold it to
me and for the same amount !
4. Poles are made of wood and they eventually rot, even treated ones, usually a
lot faster than steel rusts.
5. How can you add 20 or 30 feet to the height of your pole if you want to?
You can usually add sections to a steel guyed tower later.
6. I got a lot of static from the City of LA about getting a permit for my
pole. They finally gave me one but one of their arguments was that I was not
qualified (like the utility companies) to know if my pole was safe or not
because it could rot underground without my knowledge. The utility companies
deal with thousands of poles so they know about this stuff . . . I think I was
lucky to get a permit for it.
7. You have to custom fabricate everything for mounting anything on a pole.
There are no commercially available rotating sidemounts or methods to mount a
rotator.
I think if I thought about it for a little longer, I could add to this list . .
.
Stan
w7ni@easystreet.com
> Another thing to consider...People who are finicky about appearances, have
> often been conditioned for years... to see and accept wood poles as O.K.;
> much more so than galvanized steel, latticework towers...might be easier to
> win them over with wood....
>
> 73, DX, de Pat AA6EG/N6IJ meamonte@hotmail.com
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