On 12 Aug 2003 09:08:08 -0700, (Brian Kelly) wrote:

"DOUGLAS SNOWDEN" wrote in message ...
I am still trying to decide what type of tower to buy for a house I will be
moving into. I would like something I can handle easily by myself, meaning
either crankup or tiltover aluminum. I was thinking about maybe a Heights
or Universal aluminum 50-60ft on a tiltover base, not the foldover base. To
save money I would like to fabricate some sort of steel post along the side
of the tower, with a pulley/winch arrangement. Not being an engineer, I am
looking for ideas on how high the pole shoule be - maybe as a ratio of the
tower height and what would be a good safe diameter pipe. Am I looking for
trouble? Typical commercial foldover mechanisms are expensive. Should I
just rent a cherry picker for the occasional times I would be tilting the
tower over? As light as it would be that should be a solution.

Engineering a tower installation is not rocket science but only for
for those educated and experienced in the field of structural analyses
and design. Towers "engineered" by those who don't have appropriate
backgrounds are potential deathtraps.

Don't raise a full-height tower via a pole, cherry picker or sign
crane unless you have a grip on all the reaction forces & streses on
the structure based on the location of the lift point.

Select a catalog tower and stick 100% to the manufaucturer's
installation and operation directions. It'll cost more but you'll
sleep better.

After seeing the work I put into mine, the size of the parts, the
strength of the guys, the 17,000# guy anchors, my wife put her foot
down and said no more climbing the other guy's towers around town.
Course, she says I shouldn't be doing that kind of work for the young
guys at my age although I hear no complaints when I go up and work on
mine. http://www.rogerhalstead.com/tower.htm

We had one who was going to install a 100 foot 25G and mount the rotor
at the base. Although basically a sound idea in theory, he
unfortunately was using 1 1/2 chrome molly tube with 1/2 inch wall
and the rotor was supported between the tower legs about a foot above
the base.

I could barely manage to pick up one section of the tube and he had 6.
(I'm not all that big, but I do lift weights) Imagine the weight on
the rotor and tower base, let alone the momentum from the mass even
without the antennas.

We had a longggg talk.

He decided to mount the rotor on a separately supported steel plate
anchored to big concrete blocks on either side, but finally abandoned
the idea as getting too complex.

Roger Halstead (K8RI EN73 & ARRL Life Member)
www.rogerhalstead.com
N833R World's oldest Debonair? (S# CD-2)



Doug

N4IJ

w3rv