Hi Bob. You have a few choices.
Some folks install steps on the mast. With a strong mast this seems to work,
like 2" x .25" wall 4130 steel.
Some install a second rotor plate between the rotor and the top of the
tower. They also install the rotor so that the mast doesn't bottom out on
the rotor. This way they can remove the rotor without worrying about the
mast. You can use a muffler clamp or some other clamp as a safety device on
the mast above the middle rotor plate. For this method you would have to
take off the lower antenna before lowering the mast. Also for lowering and
raising the mast you will need something like a gin pole with the rope
attached to the mast. Don't ever try "slowly" lowering the mast by loosening
the bolts on the thrust bearing. Have a rope firmly attached and sufficient
ground crew to raise or lower the mast.
N2TK, Tony
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com]On Behalf Of Bob Gates
Sent: Sunday, September 14, 2003 13:39
To: Tower Talk
Subject: [TowerTalk] Lowering mast on fixed tower
Please excuse what, for most, is probably an elementary question. But I
feel
like Rip van Winkle, coming back into the hobby at such a late date. I have
a
question that I cannot figure out the solution to in my mind. Assume a
fixed
height tower, say Rohn 45G. Assume a rotor mounted to an accessory plate 5'
below the top, with a 20' heavy duty mast extending up through the tower,
Then
assume a yagi installed 10'-12' above the top of the tower. How does one
perform maintenance on this antenna? I assume you would need some means to
remove the rotor and lower the mast down through the tower. After work is
completed, you would then need to raise the mast back up to the desired
height
and reinstall the rotor. The problem is increased if there is another
antenna
installed on the mast, say 1' above the top of the tower. Obviously you
could
hire a crane at a gazillion dollars per hour to pick up the assembly and set
it
on the ground. But how would you do it without one? Realistically, can you
climb up the mast to work on the top antenna?
Thanks in advance,
Bob KG7KW
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
questions and ask for Sherman, W2FLA.
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_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
_______________________________________________
TowerTalk mailing list
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