I've used the jack system on both of my US towers for more that 15 years
and it's worked well for me. I have had a slight problem with my HDX89
in that the grout under the base can cause a problem as to where the
jack will fit under the bottom most member of the tower. If you get too
far out to the center of the member you will bend it. The jack needs to
be placed as far back as possible toward the raising fixture.
Julio, W4HY
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com] On Behalf Of Red
Sent: Sunday, October 29, 2006 10:18 AM
To: TowerTalk
Subject: Re: [TowerTalk] Tilting large towers
Hi, TTers;
Al Williams's analysis is correct. Rick's added note on using a jack to
start the tilt and to catch the tower when raising is a good idea. If
not restrained, it can land pretty hard.
I have used a nylon rope from the tower to a truck to start the tilt,
utilizing the stretch of the rope. Stretch the rope, relax the force
holding the tower, stretch the rope more, etc, until the tower is over
center and gravity is tilting it.
Before raising, I shorten the rope used to start the tilt, so that it
becomes taut before the tower falls onto its base. I raise the tower
until the rope becomes tight, than begin alternately letting out rope
and continuing to raise the tower, so that the rope holds the tower as
it begins to fall into place. A block of wood catches the tower leg as
it engages the mounting. After the tower is resting on the block, I
lift the tower with a pry to remove the block and let the tower down to
align the mounting holes.
I may replace the pry with a jack, as Rick suggests. I'll just leave
the jack at the height where the tower began to tilt until the tower
returns to contact the jack, then lower the jack, keeping the raising
cable under tension to keep gusts from lifting the tower off the jack,
to let the tower down gently into its mount.
73 de WOØW
Rick Karlquist wrote:
>I purchased an "aluminum racing jack" at Harbor Freight Hi
>
>
>
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