Yes sir I have.
I have a Wilson, tiltover, freestanding, rotatable. Similar to a US Tower.
My Wilson is installed next to the large masonry chimney for my house.
When I was building the chimney (I was a Mason), I installed proper J bolts
into the masonry.
(Please note there is only one A in masonry)
These bolts were located at the height of the first section.
After some study, I designed a bearing that allowed the tower to rotate
fully and be firmly attached at the first level. This really gave me a added
sense of security but was not reason to disregard wind loading and prudence.
I took a auto wheel rim from one of those tiny emergency spare tires, cut
out the center with a torch to be a firm fit for the top of the first
section of the tower.
I welded it in place.
The rim had sufficient diameter to include the cable pulley within it's
diameter.
Then I purchase from a plumbing supply house what are called riser clamps,
they are two sections of heavy steel, each section shaped like an Omega
Symbol. The two sections each have ears through which large bolts go to
squeeze around a pipe.
They are used by plumbers to support large diameter vertical pipes where
they go through floors.
>From the bolts in the chimney I made a steel tubing cage that was welded to
one of the clamp halves.
The clamps halves were the correct size to fit inside the ridges of the tire
rim.
With just a little grease inside the rim edges where the clamps rest
loosely, the tower can rotate fully and still provide lateral support at
that height.
The whole thing cost me just the price of the clamps as the rim was in the
alley for garbage pickup and I had the steel scraps lying around.
Fortunately I had the torch and welder.
If you need a picture. let me know and I'll take one and send it as an
attachment.
----- Original Message -----
From: "Jon, W4ZW" <w4zw@home.com>
To: "'TowerTalk'" <towertalk@contesting.com>
Sent: Sunday, December 09, 2001 10:24 AM
Subject: [TowerTalk] W4ZW Antenna Project Follow-up
>
> In designing a rotating mast, I need a wall mounted bearing in which the
> mast can turn. Anyone have any experience in using a wall mounted mast
> bearing?
>
> A 2.25" steel mast will be mounted in a HAM V rotor at the base and will
> extend up about 9 feet along a reinforced concrete block elevator shaft
> wall through the wall mounted bearing. I plan on mounting a small
> tribander just 4-5 feet above the wall since the entire antenna will be
> clear. The elevator shaft is a stand alone structure that rises above
> the 4th floor deck.
>
> If I can't find a simpler alternative, I will use a "L" piece of steel
> or heavy aluminum drilled for a thrust bearing mounted into the concrete
> just below the top of the shaft wall.
>
> Any ideas?
>
>
> Jon Hamlet, W4ZW
> Casey Key Island, FL
>
> "A little bit of Paradise in the Gulf of Mexico"
>
>
>
>
>
> List Sponsored by AN Wireless: AN Wireless handles Rohn tower systems,
> Trylon Titan towers, coax, hardline and more. Also check out our self
> supporting towers up to 100 feet for under $1500!!
http://www.anwireless.com
>
> -----
> FAQ on WWW: http://www.contesting.com/FAQ/towertalk
> Submissions: towertalk@contesting.com
> Administrative requests: towertalk-REQUEST@contesting.com
> Problems: owner-towertalk@contesting.com
>
>
>
List Sponsored by AN Wireless: AN Wireless handles Rohn tower systems,
Trylon Titan towers, coax, hardline and more. Also check out our self
supporting towers up to 100 feet for under $1500!! http://www.anwireless.com
-----
FAQ on WWW: http://www.contesting.com/FAQ/towertalk
Submissions: towertalk@contesting.com
Administrative requests: towertalk-REQUEST@contesting.com
Problems: owner-towertalk@contesting.com
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