I have a motorized crankup here...HD-70G by HyGain with a drum that is most
likely 4-5". The wire rope has always crushed on that drum. It is just a
fact of life. -Mike
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com] On Behalf Of Dennis Vernacchia
Sent: Wednesday, May 27, 2009 3:59 PM
To: jim Jarvis
Cc: towertalk
Subject: Re: [TowerTalk] crushed wire rope
Jim,
Bingo! you hit the nail on the head....
Coincidently, just before reading your mail, had just gotten off the phone
with
a tech guy named Bruce at Dutton
Lainson<http://www.nextag.com/norob/PtitleSeller.jsp?chnl=main&tag=716949048
&ctx=pXcBNnRR3nATsAsdb%2BjuRvryVP71YDSzQzToECtVV9mXU6igulb1%2BvsDtchGBe8FrCA
ycFKHxhijwa%2FQP4cjs4XhrGVcL99MDtXNGBtMCsoGpYAl6oeh4edxm28b4iekr37%2FjMb7wi%
2FZtf9ruN3IZHzx8LDK37pAXDqp3Ii9gk8FPmZVZ7LG6pJHuR9fX9W1&ptitle=644203920>in
Nebraska
and he verified that having a small diameter hub was the reason and that the
layers of cable are actuality, in a sense, increasing the diameter of the
hub
and that as long as the strands were not broken and I never had that section
of
wire rope exposed to a straight pull and had layers on top if the crushed
section
that I could continue to use the wire rope.
I never knew this was a common occurrence when one went to a smaller hub.
I guess one could buy some very expensive cable that might no t due that but
as a rule
he mentioned you need to be at least 3 times the wire rope diameter as
minimum hub size and
the larger the hub size ratio to the wire rope diameter, the less chance of
crushing.
Now on to getting the some RF into the air
Hopefully C U tower reflector guys in WPX CW this weekend if the creek
don't rise.
73, Dennis N6KI / NX6T ( San Diego Contest Club )
On Wed, May 27, 2009 at 12:24 PM, jim Jarvis <jimjarvis@optonline.net>wrote:
> Dennis,
> Every single DL winch I've ever had has had flattened layers at the
> inner windings. In fact, it may be every single winch, regardless of
> Mfr.
>
> I think the reason is that the compression force on the cable is a
function
> of the spool radius. For a given cable load, the smaller the radius, the
> greater
> the force on the cable itself. So, the inner layers wrap tighter, and the
> outer layers
> wrap less tight.
>
> I've replaced compressed cables with whatever I could buy at Grainger, and
> had the new ones flatten out in a year or two.
>
> N2EA
>
>
>
>
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