[TowerTalk] installing monster masts in towers(and ? two thrustbearings)

[K7LXC@aol.com]

In a message dated 6/8/2005 7:29:19 PM Pacific Daylight Time, 
towertalk-request at contesting.com writes:


>  Thrust bearings normally only need to handle side to side forces. The 
rotors
can bear the weight of the antenna(s) and mast with no problem. KC1XX tells
me that the locking bolts should all be removed from thrust bearings. Let
the rotor hold the vertical load and let the thrust bearings take the
horizontal. My thrust bearings have no locking bolts whatsoever. No
problems. When I need to take the rotor out, I put some U bolts on the mast.

    Amen to that, brother. My personal opinion is that mast vertical thrust 
bearings are highly over-rated and don't really contribute anything of value to 
the rotating system other than a being a nice mast bushing. 

    IMO the amateur need for a special thrust bearing is sort of like the 
amateur perceived need for use of  the 1-foot long "torque arms" that hams have 
put great value in for decades but in reality add little or nothing by its use. 
(The Great Ham Radio Urban Legends?!?)

    Rotators are designed to have some preload on them and their bearings. 
Why do you think all those bearings are there in the first place?!? The T2X has 
NINETY-SIX of them. 

    For the reasons posted previously, a mid thrust bearing is just a total 
waste of money. (Unless you really did need that expensive bushing - hi.)

    People SCREW UP bearings in different ways. If they'd have just left them 
off, they'd have been in better shape! And that's not speaking to the bind 
that can be easily introduced to the rotating system. And I take my hard-hat off 
to anyone who can measure 0.01" with an instrument on top of a tower. Both of 
you. 

    And don't get me started about the yucky eccentric collar TB that US 
Tower uses. They are really useless. 

    Hey - that was fun!

Cheers,
Steve    K7LXC
TOWER TECH 
Steve    K7LXC