Hi Jerry,
The tilt over base of my tower puts the hinge at about 9 feet. The boom
on my tri-band antenna is right at 18 feet....attached at the middle that
means 9 feet either side. When tilted over precisely horizontal my tower
sections are 9 feet above ground....feed points, rotor, guy attachments,
bearing, all of it. I can safely work on my tower from the stepladder height
of less than 5 feet. The tower rests when it is horizontal against a T
fixture near the top or I can let the boom rest against the ground. There's
no side forces against the rotor or mast bearing unless I settle the weight
of the tower on the boom.
Bill KC9CS
----- Original Message -----
From: "Jerry Kincade" <w5kp@swbell.net>
To: <towertalk@contesting.com>
Sent: Friday, March 15, 2002 10:51 am
Subject: Re: [Towertalk] CRANK UP TOWERS - Not a panacea
> I keep hearing this "ground level" phrase tossed around, and I'd like to
> hear from crankup owners exactly what brand and model towers they are able
> to work on at "ground level" *with antennas installed*, assuming the tower
> is installed in the clear and not next to a roof. Unless you don't have
> anything but a mast on top of it, all the sufficiently tall (70'+)
> crankup/tiltovers I looked at cannot be tilted to the point you don't need
a
> long stepladder to work around the mast, rotator, or baluns/coax. At best,
> you can get the actual mast tilted over to maybe 20'-24' or so before
> something hits the ground. So as far as I can see a TALL stepladder is
still
> needed, which is far more dangerous to climb than a tower, especially if
you
> have to handle anything heavy or long, which you eventually will. If
you've
> ever had to climb a 16' or 20' wobbly, spindly stepladder carrying a load,
> you know what I mean.
>
> Also, I'd be interested to hear how to safely change out a rotator or
check
> for binding on a thrust bearing on a fully loaded mast when the whole
thing
> is horizontal, with a zillion pounds of side pressure on the bottom end of
> the mast. Knottly problems like this likely lead people to take a chance
and
> climb a "nested" but not tilted tower, "just this once". So they've ended
up
> climbing anyway, and climbing a tower that isn't designed for climbing to
> boot. I've seen a few fixed towers I thought were too dangerous to climb,
> because of deterioration or half-baked installation. I've never seen a
> crankup I thought was safe to climb.
>
> In the end, I went with Murpy's #1 Law of Mechanics: "The Number Of
Things
> That Can Go Wrong = Number of Moving Parts Squared". So I put up 80' of
> strongly guyed Rohn 45. Using K7LXC's double safety lanyard climbing
method,
> I'm totally comfortable up there now, other than getting a bit tired if I
> have to go up two or three times in a row, but that's only because I'm a
lot
> older than most of you young whippersnappers out there.
>
> Thanks to all for all the good inputs and ideas, this is still the best
> reflector on the market.
>
> 73 and Think First, Climb Second.
> Jerry W5KP
>
>
> >Why climb? That's what the
> > point of my argument was --- the crankup tiltover can be lowered to
ground
> > level for any servicing. I replace any coax, any tower cabling, and
> > adjustments, any routine maintainance from the safety of ground level. >
>
>
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