I'm throwing this in because I haven't seen it mentioned anywhere in
this thread, and it could be very important if it's still true. As of 7
years ago (Phillystrans' mfr might have changed things since then), EHS
grips and Phillystran grips were definitely NOT the same. When I put up
my tower, P-grips were "special" in that they had a very rough
sandpaper-like coating embedded in the galvanizing (seemed to be about
36 grit or so) on the inside, and came with soft UV-resistant plastic
caps for the open ends to prevent jacket damage. The plastic-capped ends
were wrapped with Scotch 88T upon installation. The standard EHS grips I
purchased were smooth on the inside and came with the usual cast metal
"drive-on" end caps. In the literature that came with the cable,
Phillystran cautioned (in big bold capital letters) that standard EHS
grips must NOT be used on Phillystran. I don't know if this was because
of special requirements for sizing, or because EHS grips might slip on
the Phillystran's jacket. Given the "non-slip" coating inside the
P-grips, I suspect the latter. I also don't know if this caution is
applicable the other way around, but I suppose using P-grips on EHS
might damage the EHS's galvanized coating, leading to rust. At any rate,
at the time the two types of grips were most certainly not the same.
Secondly, it appears from Roger's writeup that he didn't install EHS
"tails" on his Phillystran guys. Running Philly all the way to the
ground seems to be leaving a needless opportunity for Murphy. A grass
fire, a tractor with a brush hog, a large riding mower, or (more likely
these days) a malicious kid with a pocket knife could very easily take
out one or all of the guys and take down the tower. Following the
recommendation of Phillystran folks, I ran Phillystran down to within
about 15' of the anchor end, at which point 3/16" EHS took over from
there to the anchor turnbuckle. At the meeting point of the two
different guys I simply used back-to-back thimbles--the upper one
wrapped with a special Phillystran grip and the lower one wrapped with a
standard EHS grip.
Phillystran is hell for stout in tension, light as a feather, and I
loved using it as much as I hate using EHS. It was worth every penny and
more. Seven years in the air and when I took it down mine still looked
like new. But take a healthy swipe at a piece of scrap Phillystran with
a sharp pocket knife and you'll see why the above was recommended at the
time by the Phillystran manufacturer. Assuming you run Philly all the
way to the top as I did, it's also another reason to be danged careful
swinging heavy metal objects around up there and banging them up against
the top end of the guys. If all that's changed somebody please say so.
73, Jerry W5KP
Roger (K8RI) wrote:
> I'm going to answer this on the group as a number asked this question.
> I hope I get this straight. It 's easier to do than to describe
> properly. <:-))
>
> I calculated and cut to length the guys needed plus a couple feet extra
> on each one. I had planned on using an EHS tie to the anchor so if I
> missed the length by a couple of feet I could correct the problem by
> cutting the EHS to fit. EHS lengths vary from about 10 to 14 feet.
> (What ever was needed)
> I installed the Big Grip (TM) on the end that would go on the tower.
> The excess on the other end was wound around an anchor such as a tree,
> or was driven in the yard. Sometimes a thimble will help here even if it
> has to be over size. The end that went in the Big Grip was gripped by a
> double "cam lock" like the kind used for gripping fence wire when
> stretching it (only larger). I think it was only about $3 or $4 at the
> local ACE hardware store. I don't have any photos of the procedure.
>
> I hooked a "comealong" to the cam lock and put the guy under about 400#
> tension. Then installed the Big Grip according to the instructions. The
> most difficult part was finding, or creating two anchor points the
> correct distance apart although I did have a 20' Comealong as well as a
> 20' log chain which gave me 40 feet of leeway. This was the point where
> I discovered all that steel in my welding bench may weight half a ton,
> but 400# or tension easily skids it across the floor. <:-))
>
> When winding a Big Grip became a problem I used a BIG screwdriver as a
> lever to easily get the wrap to conform. (One turn at a time...per
> side). Some times at the very end it was one wire at a time.
>
> Yes, they work very much like the "Chinese Handcuffs". The pretension
> when wrapping gives a better grip. I've never had one come loose, but
> they are not normally reusable. If one has to be redone within about a
> week it can be done once. The instructions give the specifics on that
> and I don't remember. My copy is out in the shop, but they are available
> on line.
>
> 73
>
> Roger (K8RI)
>
>
>
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