Congrats on the new QTH.
Bob, I've got a tilt-over tower at my QTH that is much smaller than what
you are proposing. I have great misgivings about attaching the winch to
your roof. 1700 lbs. is a LOT of weight to lift and could do some major
structural damage to the house, including pulling the whole thing off
into your yard.
My crew and I used a simple block-and-tackle system to raise my 48' Rohn
25G. We attached a rope to the tower at about the 40' level and draped
it across the roof (perpendicular to the front property line), which was
protected by a couple pieces of lumber covered by carpeting. We put a
block onto the trailer hitch of a full-size pick-up truck, ran the rope
through the block and to a hitch on the back of a second truck which
then pulled the rope parallel to the property line, raising the tower
with very little difficulty.
I too, have the tower guyed to the ridgeline of the house (much less
stress than what you have, though).
73 de N8AU, Jim in Raymore, MO
Date: Tue, 31 May 2005 02:31:05 -0500
From: "Bob Gates" <regates@kingwoodcable.com>
Subject: [TowerTalk] "House" Method of Raising a Tilt-Over Tower
To: "Tower Talk" <towertalk@contesting.com>
Message-ID: <007501c565b2$b4c59980$6401a8c0@upstairs>
Content-Type: text/plain; charset="iso-8859-1"
Evening/morning all,
My wife and I are celebrating tonight. We've just inked the contract to
buy a house in the Portland, OR area. Goodbye city life, back to God's
country, and adios to years of living under that dreaded term
"covenants"! This will be my first tower since 1978. And I was QRT
from 1979 to about two years ago. Have been existing with low power and
a stealth vertical, camouflaged and butted up against a big pine tree.
Well, the new place sits on top of a ridge with a 360 view (except for
some trees blocking Mt. Hood. And I'll be thankful for them when it
erupts. Much has obviously changed in 25 years, but I'm going back to
the basics of installing a tower.
Now. I have an idea. And please spare me the snide remarks. Besides,
you'll be much more tempted as you read on. In fact, as you read my
idea, many old Andy Griffith fans will be tempted to issue forth with
Barney Fife's most notable quote about Ernest T. Bass: "He's a nut!"
Because of health reasons, I cannot climb a large tower. Well, maybe I
could, but someone would have to lower me down. What I propose to do is
install 120' of Rohn 55G with four yagis. The tower will tilt over near
ground level and be raised with a roof-mounted electric winch. Now stop
that! Hear me out first. For purposes of explanation, say the house
and roof ridge line runs east-west. I do not have enough room on either
side of the house to use the derrick/W3GM method because the guy wires
won't fit. The property is only (eat your hearts out city dwellers)
about 115' wide at the north end and slopes down hill to the south,
widening as it goes. Rohn specifies the guys to be 100' from the base.
And I follow the manufacturer's instructions. Right Uncle Steve? (And
Rohn doesn't say you can't torch a section in half and install hinge
plates.) Trust me, the guys won't fit in the side yards. On the south
side of the house, the distance from the tower base to the top
of the house ridge line is 25-30'. I have a total of 3 acres, but the
farther south I move the tower the lower it gets in relation to the
crest of the ridge. Now, 120' of 55G is about 1200#. Add to that a 95#
yagi and a 55# yagi, plus rotor and mast, at the top. Another 95# yagi
will be at 90', and another 55# yagi at 60'. Total dead weight will be
approximately 1700#. Rohn specifies 3 sets of guys, but I would install
4 at 30' 60' 90' and 120'. This would help take the load of the lower
yagis.
Now for the fun part, how to get this monstrosity up in the air. An
electric winch, designed for horizontal and vertical loads, would be
installed near the peak of the roof line, on the north side of the roof.
I would heavily reinforce the space between the two rafters where the
winch would be mounted, including steel plates on the roof and below the
reinforcement, Using the bolt pattern for the winch, long bolts would
secure the winch through the top steel plate/roof/reinforcements/and
bottom steel plate. Would also install multiple wood 2x8 bracing
between multiple rafters and joists on either side of the winch mount
point. With guy wires running SE, SW and North, I would hook the winch
to the North running guy secured at the 90' point on the tower. Then
just pull that puppy up, attach all the other guys, release the guy used
for pulling the tower up from the winch and join an additional length so
it could be guyed to the north of the house with the other North running
guys. Simple.
Okay, now I'm ready. Lay it on me. And has anyone else been stupid
enough to try this?
73, Bob W7BJ/5 and about to be just old W7BJ (unless I get another call
sign to mask my identity)
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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