Jamie:
What has been suggested here from time to time, and what I did on my
own tower, is install a second bearing plate below the top one (kind of
where your rotator plate is now). On this second bearing plate many folks
have installed a second bearing. What others have done, myself included, is
install a clamp of some sort in lieu of a second bearing collar. In my case
the clamp sits about an inch above the second plate, clamped to the mast,
ready for use when I have to pull the rotator.
When that time comes, I loosen the clamp and slide it down to rest
directly in the second bearing plate. Then I can release the mast clamps on
the rotator and do what I must to the rotator itself. The top bearing and
the clamp on the second bearing plate support keep the mast and antennas
supported while the rotator is absent.
In your present case, having only one bearing plate, what some here
have done is fabricate a piece of angle aluminum with a u-bolt on one end.
This u-bolt fits around the mast just above the rotator. The opposite end
of the angle is fastened against a tower leg, to keep the angle and mast
from rotating, and to prvide the support needed to keep the mast vertical
while the rotator is absent. You might want to consider installing a second
angle and u-bolt piece, and fasten it against a second tower leg, for
additional support.
If you like the idea of haveing a second bearing plate, you might be
able to install a new rotator plate at the bottom of the top tower section.
Then you'd have a freed-up plate for a second bearing collar or clamp. To
install the second bearing, you'd merely (?) lower the mast, via a
come-along, through the second bearing, then down to the rotator in its new
position.
73 de
Gene Smar AD3F
----- Original Message -----
From: "James C. Hall, MD" <nwtcc@earthlink.net>
To: <Cqtestk4xs@aol.com>; <TOWERTALK@contesting.com>
Sent: Tuesday, October 26, 2004 1:55 PM
Subject: RE: [TowerTalk] Re: Thrust Bearing Usage
> Hello:
>
> I've been monitoring this interesting thread. I haven't had the need to
> replace a rotor (yet) and I only have one thrust bearing on the top (flat)
> plate. The rotor is 4 feet down the tower with the rest of the 20 foot C-M
> mast and two beams above. It seems to me that if you lift the mast out of
> the rotor and clamp it above the bearing, it will very much want to sway
and
> tilt with the better part of the weight above the tower. It seems you
would
> have to do some sort of stabilization just above the rotor to have a
> fighting chance - a sort of faux bearing. Am I reading this correctly or
is
> my physics off ?
>
> 73, Jamie
> WB4YDL
>
>
> -----Original Message-----
> From: towertalk-bounces@contesting.com
> [mailto:towertalk-bounces@contesting.com] On Behalf Of Cqtestk4xs@aol.com
> Sent: Monday, October 25, 2004 7:27 PM
> To: TOWERTALK@contesting.com
> Subject: Re: [TowerTalk] Re: Thrust Bearing Usage
>
>
> In a message dated 10/25/04 8:19:49 PM Greenwich Standard Time,
> ChetMoore@cox.net writes:
>
> I'm with Doug. Rotor change out is so much easier this way.
>
>
> Changing rotors out is really pretty simple even if you don't have a
thrust
>
> bearing. Simply put a u-bolt and saddle right above the cone top if you
> are
> using a cone top to hold the mast from slipping.
>
> Bill K4XS
> _______________________________________________
>
> 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.
>
> _______________________________________________
> 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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