I have a TB3 that has been in use since 1980 on two towers, with 25
SQ of Wind Load. It still works fine.
One Tower One, it was the second of two bearings, down about 2 feet
from the flat top plate. The rotor was down another 2-3 feet
(marginal...).
On Tower two, it is the top and only bearing, with the rotor down
about 9 feet.
John, K1FWF
> > The Rohn TB-3 is a non-lubricated thrust bearing. Since it only turns 1
> > RPM, the demands on it are only moderate. It's a race and ball bearing
> > arrangement and is one of the few bearings suitable for outdoor use.
> >
> >
> > 73, Steve K7LXC
> >
>
> I've talked with others who have used the Rohn bearings and they say that
> the bearings tear up pretty easily because they use aluminum races. After
> setting in one position for a long time the bearings actually make dents
> in the race. Have you seen this happen?
>
> --
>
> 73
> Kris AA5UO
> mraz@aud.alcatel.com
>
>
John D. Allen, jallen@vhfcom.com
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