[Top] [All Lists]

[Towertalk] Tailtwister won't turn.

To: <>
Subject: [Towertalk] Tailtwister won't turn.
From: (David L. Thompson)
Date: Tue, 6 Aug 2002 09:22:54 -0400
The T2X is a good rotor but requires almost perfect alignment to turn
properly without sticking.
I have mine mounted in a Tristao 71 foot crank up (now known as the TX-471
from US Tower.
Some of the other rotors will not fit inside the top section that is 12.5"
on a side.  This is also a problem with Rohn 25.  I had to cut one cross bar
that runs between horizontal sections to get the rotor in the tower.  Lou
Tristao recommended adding the ROHN 25 stress fixture which I did
to make the tower more secure at this point in the middle of the last
section of cross bars.  I had to place this bar above the widest part of the
T2X so the bell portion could move 360 degrees without hitting the bar.

The next problem the T2X faces is Hy-Gain told me is that it must be
perfectly aligned.  The rotor plates from US Tower and Tristao earlier only
align properly in two directions North and South.  They are off by several
millimeters in all other directions.   Plus the rotor plate is not bolted
down but just sits on the horizontal cross bar.  The rotor plate sits on the
top of the cross bar and is held by three vertical plates welded to the
bottom of the plate.  Unfortunately I live in Tornado alley and three
tornadoes have passed nearby.  What happens is the tornado actually picks up
the plate, rotor, WD9IIX ladder mast and all the beams and turns them as
mush as 45 degrees.
As Lou Tristao told me this was by design as otherwise the tower top would
be picked up with a possibility of breaking the cable!

I went one step further and added a second Rohn 25 stress fixture at the
horizontal cross bar to add more vertical support before the wind turned
the rotor plate.  This worked fine three years ago as a major tornado missed
me by 1/4 mile.

My theory is that this ever so slight mis-alignment causes the rotor to
start sticking and the grease to fail.  This is also why I try to service
the rotor every few years.

73 Dave K4JRB

<Prev in Thread] Current Thread [Next in Thread>