It seems that the problem is not the load (after all, it will be there after
installation), but the long distance it will "fall".
How about something like blocks of wood to catch it. Let it drop the 1/2"
to the blocks. Lift up slightly, remove a block, let it fall the next
increment, etc.
Or, as you suggest, a car jack... bring the load onto the jack, then let the
jack down.
Or (it won't take the sudden load in this case, but the idea might give you
some ideas).. use a block of ice. The load's on the block of ice, which
slowly melts and lets it down. (this has been used more than once to lower
something evenly into a hole, without using a crane). A salt block?
(dissolves pretty slow)... Big block of wax?
Maybe even something crushable: dense styrofoam?.... a tire? The airbag
approach: A piece of plywood on an inner tube might work (50 square inches
at 20 psi is 1000 pounds...)
----- Original Message -----
From: "Rick Karlquist" <richard@karlquist.com>
To: <towertalk@contesting.com>
Sent: Tuesday, January 18, 2005 2:06 PM
Subject: [TowerTalk] UST HDX5106/TRX100HD raising fixture question
> I have a UST HDX5106 tower with TRX 100HD raising fixture that I
> have just installed on the concrete base. I am almost ready to
> try tilting up the tower. It occurs to me that the tower weighs
> 3000+ lbs, thus there will be 1000+ lbs load on each leg when
> upright. What I am afraid of is that when the tower is nearly
> upright, it is going to reach a tipping point and suddenly fall
> down into place with 1000 lbs of force. It seems obvious that
> I must do something like tie a rope to the top of the bottom
> section of the tower and have it go around a pulley that lifts up a
> weight. I am estimating that I need 200 lbs of pull to counterbalance the
> tower (the 21 feet of height giving some leverage against the 3 ft base).
> Or perhaps I should put a car jack under the 3rd leg or something.
> I've never read about this issue either here on the reflector
> or in the nonexistent UST documentation. Perhaps on "normal" towers
> you can just use an "armstrong" techique, but this tower is a
> little too big for that.
_______________________________________________
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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