Julio,
I don't know if there is a "definitive" answer, but just think about the physics
of the matter. The rotor is equipped (if it is a heavy-duty type) with multiple
races containing up to a hundred or more ball bearings. (The Hy-Gain TailTwister
has three races with 138 bearings.) Is the thrust bearing this well-equipped? If
it's an ordinary thrust bearing of the type commonly available from tower
manufacturers, no. This simply means that the rotor is much better equipped to
handle the VERTICAL component of the antenna's weight than the thrust bearing
is. The rotor is NOT equipped, however, to handle side-moment loads. That's what
the thrust bearing is fundamentally there for.
By forcing the thrust bearing to do a job it's not equipped by design to do,
you're just asking for an unnecessary trip up to the top of the tower to replace
it. I've seen custom-designed thrust bearings that take the whole weight of the
antenna off of the rotor, and have a greater capacity for bearing vertical load
than the rotor does. But if you're putting that much more load on the rotor than
it's designed to handle, forget about the vertical weight -- you'll strip the
rotor out anyway with the load's rotational momentum. Stick within the specs and
let the rotor do the job it's designed to do, and you'll be golden. MOO, of
course. :-)
Bill / W5WVO
Julio Peralta wrote:
> Gentlemen I've gone trough about 150 posts in the archives trying to
> settle the issue of what a top mounted thrust bearing is supposed to
> accomplish, but I didn't find anything that I thought answered the
> question.
>
> Our club here in Tampa is getting ready to finish up a 110' R45 tower
> install with a C31 and a MAG 240N. The question came up about taking
> the weight off the rotor with the thrust bearing or whether it's
> propose is for side loading. I have my opinion but would like to hear
> from others.
>
> Is there a definitive answer to this question?
>
> Julio, W4HY
> _______________________________________________
>
> 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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_______________________________________________
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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