[TowerTalk] refurbish a Thrust bearing ?

[Stan Griffiths]

Hi Guys,

I 'm no PE, as you all should know by now, but I still have an opinion (as you
should all know by now).

Anyway, there are a couple of key pieces of information left out of the original
scenerio.  Nothing is said about wind so we have to assume zero wind and nothing is
said about the load being unbalanced on one side of the mast or the other so we have
to assume balance.  This being the case, I agree with Barry: there is no side load
on the rotator in either case.

The model you have chosen to evaluate is too simplified and does not include enough
data to allow a reasonable analysis.

Stan  w7ni@teleport.com

Barry Kutner wrote:

> On 12 Sep 98,, K7LXC@aol.com <K7LXC@aol.com> wrote:
>
> >
> > In a message dated 98-09-12 10:37:12 EDT, n7ex@athenet.net writes:
> >
> > > Explain how you would calculate the side loads on the rotator in both cases
> > >  below.
> > >
> > >  First case: The weight of the mast supported by the thrust bearing,
> > >
> > >  Second case: Weight of the mast supported entirely by the rotator, Assume
> > >  the mast  has minimal (few thousandths) of play where it  goes through the
> > >  top of the tower.
> > >
> >       The mast is the lever arm and the pivot point is where it contacts the
> > top of the tower. The mast and antenna load is trying to pry the bottom of the
> > mast that's attaced to the rotator in the opposite direction with LOTS of side
> > force.
> >
> > Cheers,  Steve   K7LXC
>
> PEs out there, correct me if I'm wrong...
> It seems to me the vertical load on the rotor, as in case 1 and 2
> above, has no effect on the side load forces (cosine of 90 = 0),
> assuming the thrust bearing is the pivot point of the system.
> 73 Barry
> --
> Barry Kutner, W2UP              Internet: w2up@mindspring.com
> Newtown, PA         FRC         alternate: barry@w2up.wells.com
>
> --
> FAQ on WWW:               http://www.contesting.com/towertalkfaq.html
> Submissions:              towertalk@contesting.com
> Administrative requests:  towertalk-REQUEST@contesting.com
> Problems:                 owner-towertalk@contesting.com
> Search:                   http://www.contesting.com/km9p/search.htm

--
66'9k'?:'<@'7:'h;'jj'7:'8m'=;':h'j@'@7'?i'=9'm<'jh





--
FAQ on WWW:               http://www.contesting.com/towertalkfaq.html
Submissions:              towertalk@contesting.com
Administrative requests:  towertalk-REQUEST@contesting.com
Problems:                 owner-towertalk@contesting.com
Search:                   http://www.contesting.com/km9p/search.htm