Hi All,
I have a question. Its a long story
I have a 40 foot self standing ( unguyed) Rohn 45G tower in 5x4x4 of
concrete. It is used to support a "small" EME array ( 4 x 10 on 15 foot
booms), total weight of about 280 lbs including AZ/EL rotor, Razer, etc.)
. I use a custom Razer ( A Hazer type clone) to lift the array up and
down when not in use. The Razer was designed with two locking legs , that
would hold the Hazer ( Razer) in place, with pull string to release. It
was designed to be lifted with a 2000lb electric winch and then the two
locking legs would hold it in place. In theory the Electric winch would
make it easy to raise and lower the array, which I do about once per
week... when I am not using the array.
I found that the Electric wench could not hold the vertical load and the
array would creep down before the locking legs could be set on one of the
45G's Horizontal cross bars and would get hung up on the diagonal bars and
do to the combination of the high tourque of the electric winch, the winch
creep and the fact its hard to see what is going on 40 feet up in the
air... the next think I know is I am bending the locking locking legs and
the damn thing is stuck and I have bent the hell out of the locking legs,
in one case, while lowering the array, the locking legs jammed, and the
the 1/8 inch cable sheared, .... luckly the array got hung up on some coax
on the way down and was saved. A 2000 lb electric winch can do a lot of
damage in just seconds.
The Razor ( Hazer) has a very well built cage and is a great product, but
between my 280lb load and the creep of a 2000 lb electric wench and the
tight spaces to land the locking legs between the diagonal and Horizontal
supports of the 45G. I needed a better way.
So I replaced the Replaced the Electric Winch, with a Fulton K1550 self
braking winch and upgraded to 3/16 cable and better pulleys. So now I
have perfect control of raising the array and of course its stops on a dime
and stays there.
So here is my question. The locking legs from all the previous problems
have been bent and weakened, they still keep failing for various reasons
jamming the array in place, causing me to have to climb the tower and
manually release them ( not much fun to climb 30 or 40 feet) and defeats
the purpose...... Since the K1550 has is self locking and can handle
1500 lbs ( although it needs to be derated for a vertical load) and my load
is only 280 lbs. DO you think I can safely do away with using the locking
legs and have the array supported by the 3/16 steel cable and the K1550?
I know the K1550 is used to lift and hold towers in place with out any
other locking system, would it work here supporting a 280lb load?
Sorry for the long story.
73
Les
W2LPL
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