Jack:
I posted something regarding the industrial bearing I installed for my
two-inch CM mast a couple of years ago:
http://lists.contesting.com/archives//html/Towertalk/2002-12/msg00213.html .
The bearing is very HD; with a single daily rotation through 360 degrees at
the top of a ham tower, it should last until ....?
Any questions, contact me direct.
73 de
Gene Smar AD3F
Rockville, MD
----- Original Message -----
From: <K4VV@aol.com>
To: <towertalk@contesting.com>
Sent: Tuesday, September 06, 2005 1:47 PM
Subject: [TowerTalk] Advice for Thrust Bearings for 3 inch Mast and
HeavyAntennas
> This message is to seek advice on the choice of thrust bearings. I have
> checked the archives, but still need advice. I am just returning to
TowerTalk
> after a two year absence.
>
> A current tower project for my new station includes a 120' PiRod tower
that
> will support two large antennas at 121' and 132' on a Chrome Molly mast.
The
> tower and mast are suitable to handle these antennas, with a safety
margin.
>
> The mast extends 7' into the top section of the tower. Three 1/2" steel
> plates are welded into the structure of the top tower section at the 112',
116'
> and 120' levels for the large ProSistel rotator and two 3" thrust
bearings. The
> bearings are intended to handle both horizontal and vertical thrust, and
> provide a stable mast support to permit removal of the rotator for
maintenance.
>
> The antennas are a full size 4-element K3LR 40m yagi (on a 48' boom and
~30
> square foot wind load) and Force 12 Ultra 80m dipole (102' long and 11.5
square
> foot wind load). The 80m dipole will be mounted parallel to the 40m boom
to
> spread the wind load more evenly.
>
> The antennas and mast together weigh about 550 pounds.
>
> Advice on the choice of thrust bearings would be appreciated. Low
> maintenance is desired. Periodic service is not an issue, whereas
replacement would be
> a challenging and costly project.
>
> Jack Hammett, K4VV
> k4vv@aol.com
> _______________________________________________
>
> 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.
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
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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