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Re: [TowerTalk] Installing guy wires

To: "'Drax Felton'" <>, <>
Subject: Re: [TowerTalk] Installing guy wires
From: "Dick Green WC1M" <>
Date: Sat, 22 Nov 2008 12:32:59 -0500
List-post: <">>
There are a number of ways to do what you want to do. Here are a few

1. It's easier to assemble the guy anchor while the target section is on the
ground. It's too late to do that with your bottom guy bracket, but you might
want to consider it for the top guy bracket (assuming you have two sets of
guys.) Before considering this method, be sure your gin pole can handle the
combined weight of the section and guy bracket.

2. If I understand what you're proposing, you'll pre-assemble one guy, with
the last section of cable still on the coil. Then you'll attach the guy to
the bracket, pull it tight (see below), and cut off the cable to minimize
the excess. I wouldn't recommend doing it that way because it's going to
take quite a bit of time to then assemble, raise and tension each of the
next two guys. I think it's better to pre-assemble all three of the guys
before beginning the procedure. This means you have to measure out the right
amount of cable, which can be done with some trigonometry and/or a piece of
graph paper. Add 5'-10' of cable to the end of each guy to make sure the
guys are long enough. If you're looping the cable through the insulators and
using wire clips (see below for a better way), then don't forget to add
extra cable for that. Once the guys are installed and tensioned, you can
either cut off the excess cable or just coil it up on the ground around the
anchor (a lot of people do that -- I did.) 

Yes, this method involves carefully calculating the guy lengths, but it
isn't hard if the tower is on relatively flat ground. In contrast, my Rohn
55 tower is on a very steep hill. The difference between the uphill and
downhill guys is on the order of 35'-45'! I used a transit level to measure
the elevation differences, repeated the measurements several times, used
trigonometry to calculate the guy lengths and verified the computations by
mapping the whole thing out on graph paper. It was actually a little more
complicated because my guys are Phillystran with EHS leaders at the bottom.
Had to calculate the lengths of Phillystran and EHS to make sure the
Phillystran was at least 10' off the ground. I added 10' of cable to each
guy, which left plenty of room for error. It all turned out great.

It required about 90' of additional cable to do it this way. But I got a
500' coil of 1/4" EHS from Hill Radio for $80, so the excess cable cost less
than $15. Well worth it.

3. It's not likely you'll be able to pull the guys taut enough by hand to
allow final tensioning with the turnbuckles. There won't be enough thread on
the turnbuckles to do that. The standard procedure is to pull the guy taut
with a come-along prior to attaching it to the turnbuckle. The fixed end of
the come-along is attached to the guy anchor or equalizer plate (if you have
a free hole other than the one you'll be using for that guy.) The best way
to attach the come-along cable to the guy cable is with a Klein grip. See
K7LXC's Champion Radio website for details. It can be done with wire clips,
but they have to be very tight to avoid slippage, and that risks damage to
the guy cable. A Klein grip is a much better solution and well worth the

The procedure is to tension the cable with the come-along, attach the cable
to the turnbuckle, release and remove the come-along, then use the
turnbuckle to reach final tension. I had the luxury of three come-alongs and
three Klein grips, so I was able to do all three guys at the same time,
slowly increasing the tension to keep the forces equal on the tower. My
target tension was 1000 lbs (Phillystran has to be tensioned to 15% of
breaking strength initially, then it will relax to the target 10% of
breaking strength.) As I recall, I tensioned the guys with the come-alongs
to about 400 lbs, then attached the guys to the turnbuckles to set the final
tension. My turnbuckles are 12 inches long, so they had plenty of thread to
set the final tension -- it doesn't take much thread once you get over a
couple hundred pounds. Note that before you start, the turnbuckles should be
opened wide, with maybe 1" or so of thread exposed at each end. I'm not
quite sure how to do this procedure with only one come-along and one Klein
grip, but imagine that with a target tension of 400 lbs you would tension
the cable to 100-200 lbs with the come-along and then attach the cable to
the turnbuckle. I'm sure others on the reflector can give you the right
amount of tension to shoot for. Bottom line, the cable needs to be taut
enough to allow the turnbuckle to finish the job, but not so taut that it's
pulling the tower off vertical to the point where the other guys can't

4. While the Rohn catalog shows how to use cable clips to attach the guy
wires to the tower, insulators and turnbuckles, the preferred method is to
use Preformed Grips. My feeling is that guy grips are a superior solution
and make the job a lot easier, especially when attaching the cable to the
turnbuckle. There's also less chance the thimbles will come out as you're
rigging the cable. BTW, regardless of whether you use grips or clips, be
sure to follow the Rohn catalog specs on the thimbles. Don't use plain-old
hardware store thimbles. These towers require special heavy-duty galvanized
thimbles. If you use standard thimbles, there's a good chance they'll
eventually get mangled under the tension and either come off or dig into the
cable. I've seen this effect on a friend's tower.

5. Don't worry about uncoiling the cable and getting it straight again.
It'll straighten right out as soon as you put tension on it.

Hope this is helpful.

73, Dick WC1M

> -----Original Message-----
> From: Drax Felton []
> Sent: Friday, November 21, 2008 10:41 PM
> To:
> Subject: [TowerTalk] Installing guy wires
> I have got my 65-foot, Rohn 25g tower built up to the 30' level  --
> uninjured and not dead thanks to this forum.  Many of you have been
> very
> helpful.  Thank you.
> It's time to install the first set of guy wires.
> Could anyone offer me advice as to the procedure?
> I was thinking that I would install the guy mounting bracket first and
> then
> raise a guy wire, which would already be assembled with several
> insulators
> breaking it into non-resonant lengths, and attach it to the first
> corner of
> the tower.
> I would then connect it to the earth anchor and equalizer plate.  The
> idea
> is to cut off the correct amount of wire from the coil.  I would then
> hand
> tighten it a little with the turnbuckle.  I would adjust all of the
> guys'
> tensions after they all are connected, getting tighter and tighter,
> walking
> in a circular pattern to keep the force even on the tower and working
> up to
> 400 lb. tension as indicated by the Loo's Tension gauge.
> Question:  How do I hold tension on the cable while I install the
> turnbuckle
> and cable clamps?  Do I just allow the turnbuckle to do all of the
> tensioning and only pull the cable hand snug into it?
> Am I missing anything?  Will my thimbles fall out while wrangling the
> cable?
> How do I uncoil the cable and get it to be straight again?
> --KB3X


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