Date: Thu, 13 Oct 2011 11:17:11 -0400 (EDT)
Subject: Re: [TowerTalk] K0XG Orbital Rotor on US Tower HDX589
In a message dated 10/12/2011 8:33:14 P.M. Pacific Daylight Time,
> Anyone out there with this configuration or mounted one of these
Orbital rotors (K0XG) on a crank-up before? I would like to exchange ideas as
this is my plan.
Where are you proposing to mount it? I'd say the only place you could
mount it feasibly is on the bottom section. Any other place and the added
weight of this brute side mount will exceed the capacity of the tower
immediately even with no antenna on it. .
If you proceed with this plan, be sure to keep your homeowner's
insurance paid up because you're going to need it.
## I see no weight listed for the K0XG unit. The Tic ring [ 1032] will
fit at either the 38' level or the 72' level on my HDX-689.
## My old style HDX-689 uses 5/16" cable + a 4:1 mech advantage. That equates
to 44 k lbs breaking. Even at 20% of breaking, that's still 8800 lbs....and
that has to take the
weight of the upper 4 x sections only...+ mast/ants, etc. The upper 4 x
sections + mast/ants
are no where near 8800 lbs, do don't sweat it.
## ok, the next 3 x sections above the base one, all have THREE 1/4"
lifting cables, PER section.
IE: one cable per each of the 3 x tower section faces. This provides for a
more even pull. There
is no way ur gonna break all 3 x cables on those sections. In order for
thise sections to come crashing down,
all 3 x cables on that section have to break.
## The very top section on my HDX-689 only has ONE 1/4" lift cable on
it..[no mech advantage].
Now, I wouldn't stuff huge weight on the very top section.... but you are not
1/4" cable is good for 7000 lbs. 20% of that = 1400 lbs.
The very top section + mast/ants is way less than 1400 lbs. The ring
rotor/orbital rotor would be installed at the
72' level, or the 55' level. At both the 72' and 55' level, those sections
have 3 x lift cables on em. IE: 3 x 7000=
21,000 lb breaking. Even at 20% of 21,000 lb = 4200lbs..and you are still
no where near that.
## You can easily put a ring rotor at the 55' / 72' level on the 89' crank
ups. Any wind load is at the 55' /72' level X
55'/72' = bending moment at the base of the tower.
## BTW...UST makes a small hand crank device, that slips over the 14" pulley
spokes. It's used IF you get a commercial AC power failure.
It's easy to turn that 14" pulley by hand. A cordless drill will also work.
IE: if the WX forecast is for 100 mph wind at midnight, then
simply get the tower cranked down asap. Worst case is the AC power goes
out...and tower is at max height....and a huge windstorm is on
it's way in < 1 hr. Once the tower is down..who cares abt the WX ?
## Both my tic 1032's weigh aprx 121 lbs. I'm guessing the orbital K0XG 's
weigh 200-350 lbs.
later........ Jim VE7RF
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