you know Wayne I left that important part out. rather and or the size
of the Thimble or Egg if used and the relationship to how the ends are
mated to the actual cable and or if the thimble/egg make those ends lay
less than desired in relation to the actual cable it is gripping, very
good point and experience you share.
Early in my 'guyed' days we tried to use a strain gage to determine the
pull stress tautness of the guyed cable, never really got very good at
using the tool and most typically just resorted to the finger and best
guess tension test to determine the final setting of the turnbuckle.
Don't know what level of tightness guys find using to grip or pull on
1/4" and example R-25 but my bet is 9400 pounds will break the weld from
the leg of deform it at the least, all the while the cable grip held.
Might be of little consultation when your shinny new tower and antenna/s
are laying in a heap on the ground. But my cable grip HELD !
mac/mc w5mc
On 2/20/2019 11:36 AM, Wayne Kline wrote:
Mac,
Not from the show me state BUT a skeptic , in the 80’s when these
GUY GRIPS started creeping into the ham community ( my limited
knowledge time wise)
There were two different ones available locally for ¼ “ EHS (
strand) 5 wire wrap and a 6 wire wrap.
Having access to a QC lab in a truck manufacturing CO ( Mack Trucks)
We set up an analisys with proper OD HD thimbles and with out
thimbles ( Read1/2 “ Dai. Pull point)
With Rohn 1/4:” EHS with it’s 6000lb breaking strength. IF memory
servs me the EHS started to delamanat, elongqate and deform around
9400 lb. pull . The Thimble also decreased it’s open end dimension.
At this point and above the strands of the cable started to elongatete
and shear ( read , catastrophic failure was not a big bang but a
strand by stran domino.
The Head Mechanical Eng. Predicted the thing PLP grip to fail before
the strand WRONG. He was really into it now. Hence his sugjestion
to removal of the thimble and just using the pulling haws ½ dia.
Pull pin and saying NOW the improper installing will cause a PLP
big grip failure !
Again the PLP line product no mater 5 wire or 6 wire did not fail..
the Rohn ¼ EHS failed before the PLP product did every time (
there were 6 full tests ) .
This was tested with only Rohn ¼ strand wire and PLP 5 and 6 wire
Big Grips
Made a beleaver out of me
Wayne W3EA
Sent from Mail <https://go.microsoft.com/fwlink/?LinkId=550986> for
Windows 10
------------------------------------------------------------------------
*From:* TowerTalk <towertalk-bounces@contesting.com> on behalf of Mac
<libbysales@austin.rr.com>
*Sent:* Wednesday, February 20, 2019 12:02:04 PM
*To:* towertalk@contesting.com
*Subject:* Re: [TowerTalk] PLP "Big Grips"
Just from the refraction of the material and then the feel it just near
has to be some form of Silica, but best of all do they ever work well..
I've never heard of a failure if even done half correct. When i first
discovered these I was skeptical and reviewed with our head of Electric
utility .. They swore by them and never a problem in long term use and
maintenance free. And PLP is the father of these having led the way best
i experience.
mac/mc w5mc
On 2/20/2019 12:12 AM, Byron Tatum wrote:
> Just out of curiosity-- I was wondering if anyone knew the exact
materials that are used to coat the inner surfaces of the PLP "Big
Grips" such as BG-2144 (1/4") or BG-2146 (5/16")? It appears to me
that a gritty material is in combination with an adhesive. I was
reading about the manufacturing process used to make a very similar
dead-end grip by a PLP competitor and it is mentioned the strands of
grip are dipped in an adhesive to bind them together, then they
mention the final application of the abrasive material to inner
surfaces. Just curious if anyone knew what the materials used were,
especially the abrasive/grit material. I recall seeing a gritty
material dropping out of older grips (of these exact two mentioned)
when taking apart older guy assemblies, plus seeing thin strips of
solidified adhesive coming off of the strands of grips. Was wondering
if the gritty material is a silica compound or something
else??Thanks, Byron W5FH
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