Chuck, I'm no engineer (I just play at being one) but it seems obvious that,
like any other part of the system, a TB needs to be rated for the loads placed
on it, both vertical and horizontal loads I would think. All I do is spread the
vertical load over the surface where the double-saddled muffler clamp meets the
TB, rather than hanging all that weight on the dents 3 or 4 little set-screws
make in the mast. Properly centered (or even close) the mast probably doesn't
put much load on the TB horizontally, but a word of caution....I'm no expert, I
just pay attention here on towertalk and the smart guys here make things pretty
clear without having to understand the math :-)
73, Jerry K3BZ
----- Original Message -----
From: Chuck Lewis
To: Jerry Keller
Sent: Thursday, July 22, 2004 4:21 PM
Subject: Re: [TowerTalk] Re: Thrust bearing
----- Original Message -----
I figure the less weight that bears on the rotator, the longer it will
last.... and TB's are cheaper than rotators!
N4NM comment:
I have always been taught that ball and roller bearings must be properly
preloaded to prolong life. Granted, these rotor bearings are running at
really slow speed, so it's not the same issue as a wheel bearing on a race
car, but intuition tells me that axial loading (within manufacturer's specs)
is beneficial in maintaining bearing alignment and reacting against lateral
(shear) loads through the plane of the bearing. I seem to remember seeing
that corroborated by a rotor manufacturer, but I can't quote the specifics.
Can anyone with some credentials weigh in here? Having a "thrust" bearing to
take the vertical load is like Mom and Apple Pie. If it's a misconception,
we need to refute it, but if the "thrust" bearing tradition is correct, I
need to crawl into my hole and shut up.
73,
Chuck, N4NM
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