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[Towertalk] Hazer windload/weightload?

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Subject: [Towertalk] Hazer windload/weightload?
From: k9zm@frontiernet.net (Greg Gobleman)
Date: Wed, 3 Apr 2002 21:02:36 -0600
Hi John,

I have a well loaded steel Hazer on a Rohn 25G tower.  The Rohn is about 59'
and is using the pointy section for the top section.  The pulley for the
Hazer has a stronger method of mounting when using a pointy top.   In
addition, my choices at the time were the pointy top or a standard straight
section.  To clear the top of the tower when swinging the antenna and have
the lowest possible mounting height on the mast, it was necessary to use the
pointy top.  A flat top changes things and I did not have that available to
me at the time.

I currently have a Telrex TB6EM tribander at 85lbs itself, a CC D40
rotatable dipole, 12' 2 meter Comet vertical, and a 12' heavy 1/4" wall
steel tube for a mast.  With cabling, T2X rotor, 6 ga. ground wire and the
messenger line, I am right at the max payload.

I have three sets of guys at present.  A set with the Rohn anti-torque
brackets at 28' and a set which I made a loop in one end and dropped over
the top of the pointy section.  Both of these sets are 3/16" rohn guy cable.
I noticed a lot of twisting movement at the top of the tower.  It had never
occurred to me that the top set was not helping to stop the twisting motion.
I have since added a set of Phillystran guys attached to the Hazer itself
and that has dampened the twisting a lot.

This system has been up 3.5 years and soon comes down and a Force 12 C3E is
replacing the Telrex.  It works great as I do not climb.  Assembly of
antennas is near ground level.  With the winch, it is necessary to use a
step ladder for most work as the Hazer is 4' or so tall.  The top of the
mast can only be reached from a ladder.  I got a couple of options.  The
rollers were a great option as was the messenger line kit.  I also had to
get the T2X mounting plates and thrust bearing.

When assembling, do not tighten anything down until it is together.  You
will be pulling something's apart to get others mounted.  Try to look ahead
in assembly and you may see some of those types of things.  When mounting
the rotor, be sure to use good steel flat washers as the lock washers will
tend to dig into the hard aluminum rotor plate.  With the wind, it will work
them loose unless you use the flat washers for the lock washers to dig into.
I have to have someone climb to the 28' level to remove that set of guys,
but all else is done by me on the ground or a short ladder.  Great system so
far.  Oh yeah, the steel Hazer is only part steel, part of it is aluminum.

73
Greg K9ZM



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