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Re: Topband: WTB: Guy wire stuff

To: "Wayne Kline" <w3ea@hotmail.com>, "low bad reflector" <topband@contesting.com>
Subject: Re: Topband: WTB: Guy wire stuff
From: "Tom W8JI" <w8ji@w8ji.com>
Reply-to: Tom W8JI <w8ji@w8ji.com>
Date: Fri, 5 Sep 2014 14:22:41 -0400
List-post: <topband@contesting.com">mailto:topband@contesting.com>
I would expect the regular grip to not fail, as you tested, because it is rated 
at 100% of 1/4 inch EHS breaking strength. Normally companies will not rate it 
that way without a huge safety margin.

The somewhat longer "big grip" styles, according to PLP, were only for added 
protection in cases where the guy lines had twisting or unwrapping issues. It 
was never even available in 1/4 inch until tower companies started selling it.

The real danger is in doing things seriously wrong, like putting the loop over 
something with inadequate radius. I've seen some pretty poor installations. 
Some installers slip the loop over the tower leg, or worse yet, over the leg 
plus a brace rod end. The rod puts a real sharp bump against the grip.


 
  ----- Original Message ----- 
  From: Wayne Kline 
  To: Carl ; JI Charles ; low bad reflector 
  Sent: Friday, September 05, 2014 1:16 PM
  Subject: RE: Topband: WTB: Guy wire stuff


   Just my  .02       
   
  Some call them Tomatoes some call them Tomottos  
   
  but even those fruits come in different size and texture  .
   
   
   When I built my station @ this QTH  4 guyed towers  with broken up guys  502 
insulators and
   
  a PRE Formed guy Fasteners . A fellow FRC member had a source for 5000' rolls 
of 1/4  Strand and 502 insulators
  and these  GUY grips  that are used in the Cable industry...  from pole to 
pole to support the cable.
   
  These  grips had the 4 twisted wire with yellow tag
   
  I had access to the Quality  Control Lab @ the Mack  Trucks test lab,
   
  We first tested  Rohn 1/4 EHS.   to facilitate the pull  I installed 3  Press 
furls on each end
   
   all test were repeated 2X    
   
  The EHS began to stretch twist and fracture @  9K  and fail @ 10.2K  lb pull
   
  Rohn PLP BIG GRIP (5) strand , with a length of  1/4 EHS   and the same furl 
at the end
                      never failed with the EHS stretching and failing at  11 + 
K lb pull
   
  now the  Shorter 4 strand twist yellow tagged  with the same length EHS ( 16" 
exposed if my memory serves me )
                       This to never Failed  and the  1/4  EHS  both times 
failing .
   
  We painted layout dye on the 1/4 ehs/grip ends  looking for pull out   NONE 
was found on either  DEAD END
   
   
  the guy grip loop end was around a solid 1 .250  rod to mimic a 502 or Rohn 
tower leg  or HD thimble.
   
  I tried Thimbles  but the press destroyed them in the  clamp down securing  
phase . 
   
  Conclusion .... 4 towers 180 plus guy grips   All 4 strand DEAD End type
   
  and 25 years and  all A - OK... I even caught a lower level guy on my ROPS 
bolt on my BIG tractor
   
  pulling so hard till I got to stop it Ripped the joint open and bent it 70 
degree on ROHN 25  !!!!
   
  AND DID NOT FAIL..... It's length was 73' with two 502's attached directly to 
the tower leg and three way equalizer plate.
   
  MY  .02    


   

  > From: km1h@jeremy.mv.com
  > To: w8ji@w8ji.com; topband@contesting.com
  > Date: Fri, 5 Sep 2014 10:46:37 -0400
  > Subject: Re: Topband: WTB: Guy wire stuff
  > 
  > > Preform comes from the name of a major grip manufacturer, not from "tower 
  > > apes".
  > > http://www.preformed.com/
  > 
  > ** Which has never been denied by anyone in this discussion. OTOH linemen 
  > and other strand installers use it as a general description thus my tower 
  > ape terminology.
  > 
  > >
  > >
  > > Dead end is the termination style of grip.
  > > 
http://www.preformed.com/index.php?option=com_phocadownload&view=category&id=15&Itemid=145
  > >
  > 
  > ** Also previously discussed
  > 
  > >
  > > The normal "Guy Grip dead end" is typically used on any shorter length 
guy 
  > > line that does not have rotational or twisting forces, and they are 
  > > normally are rated at 100% of stand breaking strength (but you should 
  > > check the catalog specs because some are less).
  > 
  > ** As are the Big Grips rated at strand strength.
  > 
  > 
  > >
  > > The "Big Grip dead end" is the Prefomed Line Products name for the longer 
  > > grips, and are better for longer guy runs that might twist.
  > >
  > > PLP manufactures custom grips that are not cataloged. PLP would probably 
  > > be a better place for application advice than Ham tower parts vendors 
(who 
  > > sell some pretty sketchy stuff at times) or Ham reflectors. :)
  > 
  > 
  > ** PLP marketing is aimed at commercial and industrial applications and not 
  > hobbiests. Their idea of a radio tower starts where most ham versions let 
  > off.
  > 
  > 
  > 
  > > Every tower failure I have seen has come from incorrectly installed guy 
  > > strand, saddle clamps, or anchors. I've seen towers where people splice 
  > > guy lines with dead ends looped through dead ends!
  > 
  > 
  > ** Ive even seen some with RatShak guy wire which is maybe 1/8. Ive never 
  > used an inline splice either.
  > 
  > 
  > It's common to see someone
  > > worry enough to buy extra long grips (which doesn't do much for 
strength), 
  > > > and then not worry about radius inside the loop (which just kills the 
  > > strength).
  > 
  > 
  > ** Good points
  > 
  > Carl
  > KM1H
  > 
  > 
  > >
  > >
  > > _________________
  > > Topband Reflector Archives - http://www.contesting.com/_topband
  > >
  > >
  > > -----
  > > No virus found in this message.
  > > Checked by AVG - www.avg.com
  > > Version: 2014.0.4765 / Virus Database: 4015/8155 - Release Date: 09/04/14
  > > 
  > 
  > _________________
  > Topband Reflector Archives - http://www.contesting.com/_topband

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