One side note - do you really believe that a captain of a wooden sailing
ship ISN'T a mechanical wiz?
Randy
N0LD
:)
----- Original Message -----
From: "alsopb" <alsopb@gloryroad.net>
To: <towertalk@contesting.com>
Sent: Saturday, May 05, 2001 21:24 PM
Subject: [TowerTalk] raising tall structures
> Good question Brian. Maybe you should ask the group.
> Possibly the "falling derrick" technique?
>
> 73, Tom N4KG
>
> On Sat, 05 May 2001 20:12:46 +0000 alsopb <alsopb@gloryroad.net>
> writes:
> > Just for curiosity, how in the old days of sailing ships did they get
> > those 100' + masts of solid wood with two foot diameters vertical--
> > especially the first one? I suppose it is easy in a shipyard.
> > However, consider this:
> >
> > I saw a recent documentary where they still use sailing ships in
> > parts
> > of the Pacific near Indonesia. On one such trip, the main mast
> > failed. The captain went ashore somewhere, bought a tree, had it
> > shaped into a suitable mast and re-installed it. I don't believe he
> > had another tall mast on the ship.
> >
> > How did he do it? They didn't say. Apparently, this is something
> > which isn't too unusual, given that the captain wasn't any kind of
> > mechanical wiz.
> >
> > 73 de Brian/K3KO
> >
> > n4kg@juno.com wrote:
> > >
> > > Picture this:
> > >
> > > You have 90 ft of R25 assembled and anchored at the base.
> > > You lift the top 5 ft. Imagine a horizontal "rope" pulling on the
> > top
> > > towards the base. The tower weighs 300 to 400 lbs depending
> > > on the weight of the lights, wires, guys etc. To hold the tower
> > > 5 ft up will require a rope tension of ( 90 / 5 ) X 200 lbs = 3600
> > lbs.
> > > The BASE must also be able to withstand this *horizontal* force,
> > > or more.
> > >
>
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>
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List Sponsor: Champion Radio Products - We'll be at the Dayton Hamvention
with all of our safety equipment and other products. Stop by booth #559 and
say hi.
<A HREF="a">http://www.championradio.com</A>
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