[amsat-bb] Thrust bearing question

[Hans BX2ABT]

Happy happy, I finally got enough money to order a roof tower for my 
future satellite antenna farm. First time ever that I can have a 
rotatable setup and I'm tickled pink. It's a 3.3 meter tower that came 
with a 3 meter steel pole and this will all be mounted on top of our 
sheet metal roof. Friends over in Holland donated a KR-400 rotator and 
Yaesu GS-050 thrust bearing and I have a question about that last one.

The tower's dimensions look like this (there are some photos and a pdf 
<http://bx2abt.com/main/data/_uploaded/file/BV6HJ-OMseriesTower.pdf> on 
bx2abt.com):

|
|     1.5 meter steel pole sticking out for 6/2/70cm yagis
|
|
--   (1) top of tower with plateau for bearing
|*
|*
|*
|*
---  (2) plateau for second bearing
|**
|**
|**
---- (3) plateau for rotator
****
****
****

Distance 1-2 is 110 cm
Distance 2-3 is 50 cm

The bearing plateaus have pre-drilled holes that accommodate the Yaesu 
GS-065 thrust bearing. The GS-050 thrust bearing I have is smaller and 
doesn't fit, but can be made fit without much hassle.

My questions - with keeping in mind that where I live we often have very 
strong storm-like winds (over 100 km/hr) and more than one typhoon every 
year (up to and sometimes over 180 km/hr):

1 - will just a top bearing and a rotator be enough, or do I need indeed 
two thrust bearings?
2 - if one will do, will the GS-050 be suitable?

I understand that thrust bearings are mainly used to reduce the weight 
of the pole on the rotator, but I am more concerned about strong winds 
warping the pole and putting sideways stress on the rotator. With the 
foul weather here everything has to be as strong as possible, but on the 
other hand, money has to be spend where it is needed, not where it's wasted.

Hope you can give some advice to this tower newbie. Cheers,

Hans
BX2ABT