Ned-
The US Tower design engineer told me, when I asked him about my slack HDX
589 pull-down cable, is that the tension is set at the factory to allow for
up to 300-350 pounds of weight load. Apparently the weight stretches the
raising cable and that tightens the pull down. If you have no or very
little load on the tower the pull down cable will normally be slack.
73,
Steve
N6SJ
-----Original Message-----
From: TowerTalk [mailto:towertalk-bounces@contesting.com] On Behalf Of
VE6WZ_Steve
Sent: Monday, July 01, 2013 6:58 PM
To: Ned K1GU; towertalk@contesting.com
Subject: Re: [TowerTalk] Slack Crank Up Cable
Ned:
I have replaced the cables on my HDX 589mdpl three times.
Slack on the pull down cable is a common issue after replacing the cables.
The slack is only evident when the tower is fully up. (obviously)
Solution:
When the tower is fully extended: 1.) loosen the cable nut holding the pull
down cable on the drum 2.) pull the slack in on the pull down cable using a
come-a-long, (or by hand) and 3.) wrap the slack tightly on the cable drum
and re-tighten the cable bolt on the drum.
Sometimes this is required a few times over the first year to fully
stabilize the cable slack.
I must confess I do not know why this happens, but I suspect it may be
because of stretch in the lift cables.
de steve ve6wz.
http://www.qsl.net/ve6wz/intro.htm
--------------------------------------------------
From: "Ned K1GU" <thewalruswaspaul@bellsouth.net>
Sent: Monday, July 01, 2013 6:18 PM
To: <towertalk@contesting.com>
Subject: [TowerTalk] Slack Crank Up Cable
> Tower: US Tower HDX 589 Crank Up. Vintage 2004, up for 9 years.
>
> Issue: There is so much slack in the pull down cable that the cable
> turns are coming off the drum when the tower is extended (fully raised
> or nearly
> so.) This allows the cable turns to overlap on the drum when the tower
> is retracted (lowered.) The spring loaded eyebolt at the cable end
> attached to the bottom of the top section has reached its maximum
> travel. That is to say, the eye of the eyebolt is right up against
> the steel bracket attached to the top section so the spring cannot
> provide any additional tension. (There is a nut on the threaded shaft
> adjacent to the eye.)
>
> History: The pull down cable has always been slack since the tower
> was first installed. Periodic adjustment of the nut that compresses
> the
> spring(s) has been necessary to keep reasonable tension on the pull
> down cable. There is no evidence of slipping at the Crosby Clamp.
>
> Help! Has anybody encountered this problem? What was the fix? Can
> the pull down cable length be safely adjusted (shortened) by a layman
> (me) by pulling it through the Crosby clamp? If a professional is
> recommended, who?
>
> Comments Solicited from UST owners and those familiar with UST
> motorized crank ups (HDX 589 MDPL, HDX 572 MDPL.) Please, no WAGs
> (wild-ass
> guesses.) -:) Send direct comments or questions to me using my call
> at arrl net. You know the format.
>
> Ned, K1GU
> East TN
> _______________________________________________
>
>
>
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