Any thoughts?
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
>
>
>
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|