I agree that tilting these things over is real iffy. I admit that mine
is overloaded. When I tilt it over, the strain is incredible and I
feel it is an accident waiting to happen. So I quit doing that. I put
a pulley on the top of the mast and use an electric winch to raise and
lower antennas. I have three big yagis on a 22 foot mast with nearly
20 feet above the tower. I put steps on the mast and climb it when
necessary.
My base is no risk. The tower is a Tri-ex LM470 70 footer. The base is
in something like 7 yards of concrete in a hole that was over 7' deep
and 5 feet square.
I feel tons safer doing this than when I climb 90 foot fixed tower.
The method I now use to raise and lower antennas is also a lot safer
than the fiddling around that goes with moving antennas up and down
guyed towers.
Michael
--- Bill Otten <res0958z@verizon.net> wrote:
> I also have a crank up/tilt-over from EZ-Way Towers. It is the Model
> RBX-50
> which extends to 52 feet (with a 10ft. galvanized mast) and supports
> a 40 sq
> ft. wind load if guyed at 110 mph. ( I'm dubious about the rating but
> that's
> what the claim was). Mine has the Wonder Post tiltover post BUT
> rather than
> just postholed into the ground my post was imbedded to 13 feet and
> just
> under 3 cu. yds of concrete poured, plus it is guyed. This past
> January I
> also replaced my cable even though the original galvanized cable
> still
> looked good -- and what had been 1/8" 7x7 bundled cable was increased
> to the
> same 3/16" 7x19 in stainless steel. This increased the tensile
> strength
> considerably to somewhere near 4400lbs. The replacement was cheap
> too! Cost
> was a miniscule .21/ft so I could recable the entire tower with
> better than
> original for about $35. I got my cable from http://versales.com/
> which
> specializes in industrial marine, desert specialty, mountain climb
> rigging
> and other wire rope specialty products. Great bunch to work with. One
> thing
> about the old EZ-Way towers was the brake mechanism it had was fairly
> substantial. Mine uses a spring return on it so if you are lowering
> the
> tower you must be pulling on the brake release lanyard or it will
> snap back
> into place and stop the tower. When the winds blow here in Florida's
> Gulf
> of Mexico coast (hurricanes, etc.) the tower comes down within 20
> minutes
> and when tilted over stands a mere 10' off the ground parallel.
> Oddly, the
> brochure for this tower shows it capable of what was called a
> 'half-tilt'
> mode but anyone who's ever cranked one over knows the incredible
> tension
> that crank-over pulley and cable is under at that point, not to
> mention the
> lever effect 25' of tower half tilted must have on the base fixture.
> I DO
> NOT recommend this as even a remotely good idea.
>
> Bill KC9CS
>
> -- Original Message -----
> From: "K6RB" <k6rb@baymoon.com>
> To: <Towertalk@contesting.com>
> Sent: Thursday, March 14, 2002 12:03 pm
> Subject: Re: [Towertalk] CRANK UP TOWERS
>
>
> > I have an old Tri-Ex tower (W-51) that was put up in August 1984
> and on
> > which I have changed the cables only once - a month ago! It
> survived about
> > half a dozen storms of 80 mph peak winds, and the cable never
> failed. It
> had
> > a 10 foot galvanized mast and a KLM KT 34-XA on it until last
> August. It
> now
> > carries a 20 foot chromoloy mast and stacked Force 12 antennas. I
> replaced
> > the original cables with new 3/16 , 7x19 cables and plan to replace
> them
> > more frequently with the greater load the tower now carries. In the
> past I
> > left it at full height unless there was a storm forecast or strong
> winds
> > that were evident. Now, I keep it up when I know I'll be using the
> station
> > frequently, but retract it when it will be unused for long periods.
>
>
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