Nylon 3 strand will elongate about 50% before breakage. That property
is great for anchoring or towing but awful for guying or lifting. The
energy that can be stored in a piece of nylon rope is impressive and
some very nasty accidents have happened since nylon rope also makes a
very good saw when it relaxes from breaking.
Because sailboat racers want no stretch lines for halyards and sheets,
several low/no (some even less then 7x19 wire rope) stretch rope
materials are now available, at reasonable to astronomic prices. New
England Ropes StaSet polyester braid in 7/16" diameter is my favorite
for gin poles, lifting, rigging, block and tackle work, etc. A moderate
price, easy handling and knots, very durable, fairly low stretch (4% at
30% of breaking strength). see
http://www.neropes.com/Datasheets/MAR_STASET.pdf
Most marine chandlers carry it, e.g. West Marine. Also, on ebay.
Grant KZ1W
On 3/30/2011 3:13 PM, john@kk9a.com wrote:
> I am curious how temporary guys could stretch so much to lay a tower on its
> side, perhaps the guy anchors were very far away? The Trucker's Hitch is
> great advice, I have used this knot to for securing tower or reels of
> hardline when transporting them home.
>
> John KK9A
>
>
>
> To: towertalk@contesting.com
> Subject: [TowerTalk] Temporary guys
> From: K7LXC@aol.com
> Date: Wed, 30 Mar 2011 14:33:09 EDT
> List-post:<towertalk@contesting.com">mailto:towertalk@contesting.com>
>
> Howdy, TowerTalkians --
>
> I just read a portion of the ARRL tower book where the author recounts
> an episode where the temporary rope guys holding the bottom sections of
> the tower stretched so much that he found himself laying on the ground with
> the tower laying on top of him. Similarly, W2GD had the same thing happen
> to
> him. In neither case was the climber terribly injured but they were lucky
> to fall onto soft ground.
>
> If you're going to do something like this (the use of temporary guys
> has its applications) and use rope, the best thing to do is to use a
> 'trucker's hitch' which gives you a 2:1 mechanical advantage and provides
> much
> more tension on the rope to minimize any stretch or failure.
>
> In the book, the author says he only uses steel temporary guys now -
> lesson learned. But using a trucker's hitch will make using rope guys
> viable
> and safe.
>
> Cheers,
> Steve K7LXC
> TOWER TECH
>
> _______________________________________________
>
>
>
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